diff options
Diffstat (limited to 'lib/observer/doc/src/ttb_ug.xml')
| -rw-r--r-- | lib/observer/doc/src/ttb_ug.xml | 1056 |
1 files changed, 550 insertions, 506 deletions
diff --git a/lib/observer/doc/src/ttb_ug.xml b/lib/observer/doc/src/ttb_ug.xml index 08093a9451..34591ae8de 100644 --- a/lib/observer/doc/src/ttb_ug.xml +++ b/lib/observer/doc/src/ttb_ug.xml @@ -1,23 +1,24 @@ -<?xml version="1.0" encoding="latin1" ?> +<?xml version="1.0" encoding="utf-8" ?> <!DOCTYPE chapter SYSTEM "chapter.dtd"> <chapter> <header> <copyright> - <year>2002</year><year>2011</year> + <year>2002</year><year>2016</year> <holder>Ericsson AB. All Rights Reserved.</holder> </copyright> <legalnotice> - The contents of this file are subject to the Erlang Public License, - Version 1.1, (the "License"); you may not use this file except in - compliance with the License. You should have received a copy of the - Erlang Public License along with this software. If not, it can be - retrieved online at http://www.erlang.org/. - - Software distributed under the License is distributed on an "AS IS" - basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See - the License for the specific language governing rights and limitations - under the License. + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. </legalnotice> @@ -31,78 +32,85 @@ <section> <title>Introduction</title> - <p>The Trace Tool Builder is a base for building trace tools for - single node or distributed erlang systems. It requires the - <c>runtime_tools</c> application to be available on the traced + <p>Trace Tool Builder is a base for building trace tools for + single node or distributed Erlang systems. It requires the + Runtime_Tools application to be available on the traced node. </p> - <p>The main features of the Trace Tool Builder are:</p> + <p>The following are the main features of Trace Tool Builder:</p> <list type="bulleted"> - <item>Start tracing to file ports on several nodes with one + <item>Start tracing to file ports on many nodes with one function call.</item> - <item>Write additional information to a trace information file, + <item>Write more information to a trace information file, which is read during formatting.</item> - <item>Restoring of previous configuration by maintaining a + <item>Restore previous configuration by maintaining a history buffer and handling configuration files.</item> - <item>Some simple support for sequential tracing.</item> - <item>Formatting of binary trace logs and merging of logs from + <item>Provide some simple support for sequential tracing.</item> + <item>Format binary trace logs and merge logs from multiple nodes.</item> </list> - <p>The intention of the Trace Tool Builder is to serve - as a base for tailor made trace tools, but you may use it directly - from the erlang shell (it may mimic <c>dbg</c> behaviour while - still providing useful additions like match specification shortcuts). - The application only - allows the use of file port tracer, so if you would like - to use other types of trace clients you will be better off - using <c>dbg</c> directly instead.</p> + <p>The intention of Trace Tool Builder is to serve + as a base for tailor-made trace tools, but it can also be used directly + from the Erlang shell (it can mimic <c>dbg</c> behaviour while + still providing useful additions, such as match specification shortcuts). + Trace Tool Builder only allows the use of file port tracer, so to use + other types of trace clients it is better to use <c>dbg</c> directly.</p> </section> <section> <title>Getting Started</title> - <p>The <c>ttb</c> module is the interface to all functions in the - Trace Tool Builder. To get started the least you need to do is to - start a tracer with <c>ttb:tracer/0/1/2</c>, and set the required - trace flags on the processes you want to trace with - <c>ttb:p/2</c>. Then, when the tracing is completed, you must stop - the tracer with <c>ttb:stop/0/1</c> and format the trace log with - <c>ttb:format/1/2</c> (as long as there is anything to format, of - course). - </p> - <p><c>ttb:tracer/0/1/2</c> opens a trace port on each node - that shall be traced. By default, trace messages are written - to binary files on remote nodes(the binary trace log). + <p>Module <c>ttb</c> is the interface to all functions in + Trace Tool Builder.</p> + <p>To get started, the least you need to do is to + start a tracer with + <seealso marker="ttb#tracer/0"><c>ttb:tracer/0,1,2</c></seealso>, + and set the required + trace flags on the processes you want to trace with + <seealso marker="ttb#p/2"><c>ttb:p/2</c></seealso>.</p> + <p>When the tracing is completed, stop the tracer with + <seealso marker="ttb#stop/0"><c>ttb:stop/0,1</c></seealso> + and format the trace log with + <seealso marker="ttb#format/1"><c>ttb:format/1,2</c></seealso> + (if there is anything to format). </p> - <p><c>ttb:p/2</c> specifies which processes shall be - traced. Trace flags given in this call specify what to trace on - each process. You can call this function several times if you like - different trace flags to be set on different processes. - </p> - <p>If you want to trace function calls (i.e. if you have the - <c>call</c> trace flag set on any of your processes), you must + <p><em>Useful functions:</em></p> + <taglist> + <tag><c>ttb:tracer/0,1,2</c></tag> + <item><p>Opens a trace port on each node to be traced. By default, + trace messages are written to binary files on remote nodes (the + binary trace log).</p></item> + <tag><c>ttb:p/2</c></tag> + <item><p>Specifies the processes to be traced. Trace flags specified + in this call specify what to trace on each process. This function can be + called many times if you like different trace flags to be set on different + processes.</p></item> + <tag><c>ttb:tp/2,3,4</c> or <c>ttb:tpl/2,3,4</c></tag> + <item><p>If you want to trace function calls (that is, if you have + trace flag <c>call</c> set on any process), you must also set trace patterns on the required function(s) with - <c>ttb:tp</c> or <c>ttb:tpl</c>. A function is only traced if it - has a trace pattern. The trace pattern specifies how to trace the + <seealso marker="ttb#/0"><c>ttb:tp/2,3,4</c></seealso> or + <seealso marker="ttb#/0"><c>ttb:tpl/2,3,4</c></seealso>. + A function is only traced + if it has a trace pattern. The trace pattern specifies how to trace the function by using match specifications. Match specifications are - described in the User's Guide for the erlang runtime system - <c>erts</c>. - </p> - <p><c>ttb:stop/0/1</c> stops tracing on all nodes, deletes all - trace patterns and flushes the trace port buffer. - </p> - <p><c>ttb:format/1/2</c> translates the binary trace logs into - something readable. By default <c>ttb</c> presents each trace - message as a line of text, but you can also write your own handler - to make more complex interpretations of the trace information. A - trace log can even be presented graphically via the Event Tracer - application. Note that if you give the <c>format</c> option to - <c>ttb:stop/1</c> the formatting is automatically done when - stopping <c>ttb</c>. - </p> - + described in the + <seealso marker="erts:users_guide">ERTS User's Guide</seealso>.</p></item> + <tag><c>ttb:stop/0,1</c></tag> + <item><p>Stops tracing on all nodes, deletes all trace patterns, and + flushes the trace port buffer.</p></item> + <tag><c>ttb:format/1/2</c></tag> + <item><p>Translates the binary trace logs into something readable. + By default, <c>ttb</c> presents each trace message as a line of text, + but you can also write your own handler to make more complex interpretations + of the trace information. A trace log can also be presented graphically + with application Event Tracer (ET).</p> + <p>If option <c>format</c> is specified to <c>ttb:stop/1</c>, the formatting + is automatically done when stopping <c>ttb</c>.</p></item> + </taglist> + <section> - <title>Example: Tracing the local node from the erlang shell</title> - <p>This small module is used in the example:</p> + <title>Tracing Local Node from Erlang Shell</title> + <p>The following small module is used in the subsequent example:</p> <code type="none"> -module(m). -export([f/0]). @@ -113,25 +121,25 @@ f() -> From ! {self(),Now} end. </code> <p>The following example shows the basic use of <c>ttb</c> from - the erlang shell. Default options are used both for starting the - tracer and for formatting (the custom fetch dir is however provided). - This gives a trace log named <c>Node-ttb</c> in the newly-created - directory, where <c>Node</c> is the name of the node. The + the Erlang shell. Default options are used both for starting the + tracer and for formatting (the custom fetch directory is however provided). + This gives a trace log named <c>Node-ttb</c> in the newly created + directory, where <c>Node</c> is the node name. The default handler prints the formatted trace messages in the - shell.</p> - <code type="none"><![CDATA[ + shell:</p> + <pre> (tiger@durin)47> %% First I spawn a process running my test function -(tiger@durin)47> Pid = spawn(m,f,[]). -<0.125.0> +(tiger@durin)47> <input>Pid = spawn(m,f,[]).</input> +<0.125.0> (tiger@durin)48> (tiger@durin)48> %% Then I start a tracer... -(tiger@durin)48> ttb:tracer(). +(tiger@durin)48> <input>ttb:tracer().</input> {ok,[tiger@durin]} (tiger@durin)49> (tiger@durin)49> %% and activate the new process for tracing (tiger@durin)49> %% function calls and sent messages. -(tiger@durin)49> ttb:p(Pid,[call,send]). -{ok,[{<0.125.0>,[{matched,tiger@durin,1}]}]} +(tiger@durin)49> <input>ttb:p(Pid,[call,send]).</input> +{ok,[{<0.125.0>,[{matched,tiger@durin,1}]}]} (tiger@durin)50> (tiger@durin)50> %% Here I set a trace pattern on erlang:now/0 (tiger@durin)50> %% The trace pattern is a simple match spec @@ -139,33 +147,33 @@ f() -> (tiger@durin)50> %% traced. Refer to the reference_manual for (tiger@durin)50> %% the full list of match spec shortcuts (tiger@durin)50> %% available. -(tiger@durin)51> ttb:tp(erlang,now,return). +(tiger@durin)51> <input>ttb:tp(erlang,now,return).</input> {ok,[{matched,tiger@durin,1},{saved,1}]} (tiger@durin)52> (tiger@durin)52> %% I run my test (i.e. send a message to (tiger@durin)52> %% my new process) -(tiger@durin)52> Pid ! self(). -<0.72.0> +(tiger@durin)52> <input>Pid ! self().</input> +<0.72.0> (tiger@durin)53> (tiger@durin)53> %% And then I have to stop ttb in order to flush (tiger@durin)53> %% the trace port buffer -(tiger@durin)53> ttb:stop([return, {fetch_dir, "fetch"}]). +(tiger@durin)53> <input>ttb:stop([return, {fetch_dir, "fetch"}]).</input> {stopped, "fetch"} (tiger@durin)54> (tiger@durin)54> %% Finally I format my trace log -(tiger@durin)54> ttb:format("fetch"). -({<0.125.0>,{m,f,0},tiger@durin}) call erlang:now() -({<0.125.0>,{m,f,0},tiger@durin}) returned from erlang:now/0 -> +(tiger@durin)54> <input>ttb:format("fetch").</input> +({<0.125.0>,{m,f,0},tiger@durin}) call erlang:now() +({<0.125.0>,{m,f,0},tiger@durin}) returned from erlang:now/0 -> {1031,133451,667611} -({<0.125.0>,{m,f,0},tiger@durin}) <0.72.0> ! -{<0.125.0>,{1031,133451,667611}} -ok ]]></code> +({<0.125.0>,{m,f,0},tiger@durin}) <0.72.0> ! +{<0.125.0>,{1031,133451,667611}} +ok</pre> </section> <section> - <title>Example: Build your own tool</title> - <p>This small example shows a simple tool for "debug tracing", - i.e. tracing of function calls with return values.</p> + <title>Build Your Own Tool</title> + <p>The following example shows a simple tool for "debug tracing", + that is, tracing of function calls with return values:</p> <code type="none"><![CDATA[ -module(mydebug). -export([start/0,trc/1,stop/0,format/1]). @@ -227,124 +235,127 @@ do_print(Out,{trace_ts,P,return_from,{M,F,A},R,Ts},N) -> "Return value :~p~n~n", [N,Ts,P,M,F,A,R]). ]]></code> <p>To distinguish trace logs produced with this tool from other - logs, the <c>file</c> option is used in <c>tracer/2</c>. The - logs will therefore be fetched to a directory named + logs, option <c>file</c> is used in + <seealso marker="ttb#tracer/2"><c>tracer/2</c></seealso>. The + logs are therefore fetched to a directory named <c>ttb_upload_debug_log-YYYYMMDD-HHMMSS</c> </p> - <p>By using the <c>handler</c> option when starting the tracer, + <p>By using option <c>handler</c> when starting the tracer, the information about how to format the file is stored in the trace information file (<c>.ti</c>). This is not necessary, as - it might be given at the time of formatting instead. It can - however be useful if you e.g. want to automatically format your - trace logs by using the <c>format</c> option in - <c>ttb:stop/1</c>. It also means that you don't need any - knowledge of the content of a binary log to be able to format it - the way it was intended. If the <c>handler</c> option is given - both when starting the tracer and when formatting, the one given - when formatting is used. + it can be specified when formatting instead. However, It can + be useful if you, for example, want to format trace logs automatically + using option <c>format</c> in <c>ttb:stop/1</c>. Also, you do not need + any knowledge of the content of a binary log to format it the way it + is intended. If option <c>handler</c> is specified both when starting + the tracer and when formatting, the one specified when formatting is used. </p> - <p>The <c>call</c> trace flag is set on all processes. This - means that any function activated with the <c>trc/1</c> command - will be traced on all existing and new processes. + <p>Trace flag <c>call</c> is set on all processes. This + means that any function activated with command <c>trc/1</c> + is traced on all existing and new processes. </p> </section> </section> <section> - <title>Running the Trace Tool Builder against a remote node</title> + <title>Running Trace Tool Builder against Remote Node</title> <p>The Observer application might not always be available on the - node that shall be traced (in the following called the "traced - node"). It is still possible to run the Trace Tool Builder from + node to be traced (in the following called the "traced + node"). However, Trace Tool Builder can still be run from another node (in the following called the "trace control node") as - long as + long as the following is fulfilled: </p> <list type="bulleted"> <item>The Observer application is available on the trace control node.</item> - <item>The Runtime Tools application is available on both the + <item>The Runtime_Tools application is available on both the trace control node and the traced node.</item> </list> - <p>If the Trace Tool Builder shall be used against a remote node, + <p>If Trace Tool Builder is to be used against a remote node, it is highly recommended to start the trace control node as <em>hidden</em>. This way it can connect to the traced node - without the traced node "seeing" it, i.e. if the <c>nodes()</c> - BIF is called on the traced node, the trace control node will not - show. To start a hidden node, add the <c>-hidden</c> option to the - <c>erl</c> command, e.g.</p> - <code type="none"> -% erl -sname trace_control -hidden </code> + without being "seen" by it, that is, if the <c>nodes()</c> + BIF is called on the traced node, the trace control node does not + show. To start a hidden node, add option <c>-hidden</c> to the + <c>erl</c> command, for example:</p> + <pre> +% <input>erl -sname trace_control -hidden</input></pre> <section> - <title>Diskless node</title> + <title>Diskless Node</title> <p>If the traced node is diskless, <c>ttb</c> must be started from - a trace control node with disk access, and the <c>file</c> option - must be given to the <c>tracer/2</c> function with the value - <c>{local, File}</c>, e.g.</p> - <code type="none"> -(trace_control@durin)1> ttb:tracer(mynode@diskless,{file,{local, -{wrap,"mytrace"}}}). -{ok,[mynode@diskless]} </code> + a trace control node with disk access, and option <c>file</c> + must be specified to function <c>tracer/2</c> with value + <c>{local, File}</c>, for example:</p> + <pre> +(trace_control@durin)1> <input>ttb:tracer(mynode@diskless, + {file,{local,{wrap,"mytrace"}}}).</input> +{ok,[mynode@diskless]}</pre> </section> </section> <section> - <title>Additional tracing options</title> - <p>When setting up a trace, several features may be turned on:</p> + <title>More Tracing Options</title> + <p>When setting up a trace, the following features can also be activated:</p> <list type="bulleted"> - <item>time-constrained tracing,</item> - <item>overload protection,</item> - <item>autoresuming.</item> + <item>Time-constrained tracing</item> + <item>Overload protection</item> + <item>Autoresume</item> + <item><c>dbg</c> mode</item> </list> <section> - <title>Time-constrained tracing</title> - <p>Sometimes, it may be helpful to enable trace for a - given period of time (i.e. to monitor a system for 24 hours - or half of a second). This may be done by issuing additional - <c>{timer, TimerSpec}</c> option. If <c>TimerSpec</c> has the + <title>Time-Constrained Tracing</title> + <p>It can sometimes be helpful to enable trace for a + specified period of time (for example, to monitor a system for 24 hours + or half a second). This can be done with option + <c>{timer, TimerSpec}</c>. If <c>TimerSpec</c> has the form of <c>MSec</c>, the trace is stopped after <c>MSec</c> - milliseconds using <c>ttb:stop/0</c>. If any additional options - are provided (<c>TimerSpec = {MSec, Opts}</c>), <c>ttb:stop/1</c> - is called instead with <c>Opts</c> as the arguments. The timer - is started with <c>ttb:p/2</c>, so any trace patterns should - be set up before. <c>ttb:start_trace/4</c> - always sets up all pattern before invoking <c>ttb:p/2</c>. - Note that due to network and processing delays the the period - of tracing is approximate. - The example below shows how to set up a trace which will be - automatically stopped and formatted after 5 seconds - </p><code> -(tiger@durin)1>ttb:start_trace([node()], - [{erlang, now,[]}], - {all, call}, - [{timer, {5000, format}}]). -</code> + milliseconds using + <seealso marker="ttb#stop/0"><c>ttb:stop/0</c></seealso>. If more + options are provided (<c>TimerSpec = {MSec, Opts}</c>), + <seealso marker="ttb#stop/1"><c>ttb:stop/1</c></seealso> + is called instead with <c>Opts</c> as argument.</p> + <p>The timer is started with + <seealso marker="ttb#p/2"><c>ttb:p/2</c></seealso>, so any trace patterns + must be set up in advance. + <seealso marker="ttb#start_trace/4"><c>ttb:start_trace/4</c></seealso> + always sets up all patterns before invoking <c>ttb:p/2</c>.</p> + <p>The following example shows how to set up a trace that is + automatically stopped and formatted after 5 seconds: + </p><pre> +(tiger@durin)1> <input>ttb:start_trace([node()], + [{erlang, now,[]}], + {all, call}, + [{timer, {5000, format}}]).</input></pre> + <note><p>Because of network and processing delays, the period + of tracing is approximate.</p></note> + </section> <section> - <label>Overload protection</label> - <p>When tracing live systems, special care needs to be always taken - not to overload a node with too heavy tracing. <c>ttb</c> provides - the <c>overload</c> option to help to address the problem.</p> - <p><c>{overload, MSec, Module, Function}</c> instructs the ttb backend - (called <c>observer_backend</c>, part of the <c>runtime_tools</c> - application) to perform overload check every <c>MSec</c> milliseconds. - If the check (namely <c>Module:Function(check)</c>) returns + <title>Overload Protection</title> + <p>When tracing live systems, always take special care to not + overload a node with too heavy tracing. <c>ttb</c> provides + option <c>overload</c> to address this problem.</p> + <p><c>{overload, MSec, Module, Function}</c> instructs the <c>ttb</c> back end + (a part of the <seealso marker="runtime_tools:index">Runtime_Tools</seealso> + application) to perform overload check every <c>MSec</c> millisecond. + If the check (named <c>Module:Function(check)</c>) returns <c>true</c>, tracing is disabled on the selected node.</p> <p>Overload protection activated on one node does not affect other nodes, where the tracing continues as normal. - <c>ttb:stop/0/1</c> fetches data from all clients, including everything - that has been collected before overload protection was activated. - Note that - changing trace details (with <c>ttb:p</c> and <c>ttb:tp/tpl...</c>) - once overload protection gets activated in one of the traced - nodes is not permitted in order not to allow trace setup - to be inconsistent between nodes. - </p> - <p><c>Module:Function</c> provided with the <c>overload</c> option must - handle three calls: <c>init</c>, <c>check</c> and <c>stop</c>. <c>init</c> - and <c>stop</c> allows to perform some setup and teardown required by - the check. An overload check module could look like this (note that - <c>check</c> is always called by the same process, so <c>put</c> and - <c>get</c> are possible). - </p><code> + <c>ttb:stop/0,1</c> fetches data from all clients, including everything + collected before the activation of overload protection.</p> + + <note><p> + It is not allowed to change trace details + (with <c>ttb:p</c> and <c>ttb:tp/tpl...</c>) once overload + protection is activated in one of the traced nodes. This is to + avoid trace setup being inconsistent between nodes.</p></note> + + <p><c>Module:Function</c> provided with option <c>overload</c> must + handle three calls: <c>init</c>, <c>check</c>, and <c>stop</c>. <c>init</c> + and <c>stop</c> allow some setup and teardown required by + the check. An overload check module can look as follows: + </p><code type="none"> -module(overload). -export([check/1]). @@ -361,33 +372,37 @@ check(check) -> end; check(stop) -> get(pid) ! stop.</code> + <note><p> + <c>check</c> is always called by the same process, so <c>put</c> and + <c>get</c> are possible.</p></note> </section> <section> <title>Autoresume</title> - <p>It is possible that a node (probably a buggy one, hence traced) - crashes. In order to automatically resume tracing on the node - as soon as it gets back, <c>resume</c> has to be used. When - it is, the failing node tries to reconnect - to trace control node as soon as <c>runtime tools</c> is started. - This implies that <c>runtime_tools</c> must be included in - other node's startup chain (if it is not, one could still - resume tracing by starting <c>runtime_tools</c> manually, - i.e. by an RPC call).</p> - <p>In order not to loose the data that the failing node stored - up to the point of crash, the control node will try to fetch - it before restarting trace. This must happen within the allowed - time frame or is aborted (default is 10 seconds, can be customized with - <c>{resume, MSec}</c>). The data fetched this way is then - merged with all other traces.</p> - <p>Autostart feature requires additional data to be stored on + <p>A node can crash (probably a buggy one, hence traced). + Use <c>resume</c> to resume tracing on the node automatically + when it gets back. The failing node then tries to reconnect + to trace control node when <c>Runtime_Tools</c> is started. + This implies that <c>Runtime_Tools</c> must be included in + the startup chain of other nodes (if not, you can still + resume tracing by starting <c>Runtime_Tools</c> manually, + that is, by an RPC call).</p> + <p>To not lose the data that the failing node stored + up to the point of crash, the control node tries to fetch + it before restarting trace. This must occur within the allowed + time frame, otherwise it is aborted (default is 10 seconds, but it + can be changed with <c>{resume, MSec}</c>). The data fetched + this way is then merged with all other traces.</p> + <p>The autostart feature requires more data to be stored on traced nodes. By default, the data is stored automatically - to the file called "ttb_autostart.bin" in the traced node's cwd. - Users may decide to change this behaviour (i.e. on diskless + to the file named "ttb_autostart.bin" in the currect working directory + (cwd) of the traced node. + Users can change this behaviour (that is, on diskless nodes) by specifying their own module to handle autostart data storage and retrieval (<c>ttb_autostart_module</c> - environment variable of <c>runtime_tools</c>). Please see the - ttb's reference manual to see the module's API. This example - shows the default handler</p> + environment variable of <c>runtime_tools</c>). For information + about the API, see module + <seealso marker="ttb"><c>ttb</c></seealso>. + The following example shows the default handler:</p> <code> -module(ttb_autostart). -export([read_config/0, @@ -406,54 +421,60 @@ read_config() -> end. write_config(Data) -> - file:write_file(?AUTOSTART_FILENAME, term_to_binary(Data)). - </code> - <p>Remember that file trace ports buffer the data + file:write_file(?AUTOSTART_FILENAME, term_to_binary(Data)).</code> + + <note><p>Remember that file trace ports buffer the data by default. If the node crashes, trace messages are not - flushed to the binary log. If the chance of failure is - high, it might be a good idea to automatically flush - the buffers every now and then. Passing <c>{flush, MSec}</c> - as one of <c>ttb:tracer/2</c> option flushes all buffers - every <c>MSec</c> milliseconds.</p> + flushed to the binary log. If the risk of failure is + high, it can be a good idea to flush the buffers every + now and then automatically. Passing <c>{flush, MSec}</c> + as an option of <c>ttb:tracer/2</c> flushes all buffers + every <c>MSec</c> millisecond.</p></note> </section> <section> - <title>dbg mode</title> - <p>The <c>{shell, ShellType}</c> option allows to make <c>ttb</c> - operation similar to <c>dbg</c>. Using <c>{shell, true}</c> + <title>dbg Mode</title> + <p>Option <c>{shell, ShellType}</c> allows making <c>ttb</c> + operation similar to + <seealso marker="runtime_tools:dbg"><c>dbg</c></seealso>. + Using <c>{shell, true}</c> displays all trace messages in the shell before storing them. <c>{shell, only}</c> additionally disables message storage - (so that the tool behaves exactly like dbg). This is allowed - only with ip trace ports (<c>{trace, {local, File}}</c>). + (making the tool to behave exactly like <c>dbg</c>). This is + allowed only with IP trace ports (<c>{trace, {local, File}}</c>). </p> - <p>The command <c>ttb:tracer(dbg)</c> is a shortcut for the pure-dbg - mode (<c>{shell, only}</c>).</p> + <p>Command <c>ttb:tracer(dbg)</c> is a shortcut for the pure + <c>dbg</c> mode (<c>{shell, only}</c>).</p> </section> </section> <section> <marker id="trace_info"></marker> - <title>Trace Information and the .ti File</title> - <p>In addition to the trace log file(s), a file with the extension - <c>.ti</c> is created when the Trace Tool Builder is started. This - is the trace information file. It is a binary file, and it + <title>Trace Information and File .ti</title> + <p>In addition to the trace log file(s), a file with extension + <c>.ti</c> is created when Trace Tool Builder is started. This + is the trace information file. It is a binary file, which contains the process information, trace flags used, the name of - the node to which it belongs and all information written with the - <c>write_trace_info/2</c> function. .ti files are always fetched - with other logs when the trace is stopped. + the node to which it belongs, and all information written with + function + <seealso marker="ttb#write_trace_info/2"><c>ttb:write_trace_info/2</c></seealso>. + <c>.ti</c> files are always fetched with other logs when the trace is stopped. </p> <p>Except for the process information, everything in the trace information file is passed on to the handler function when - formatting. The <c>TI</c> parameter is a list of + formatting. Parameter <c>TI</c> is a list of <c>{Key,ValueList}</c> tuples. The keys <c>flags</c>, - <c>handler</c>, <c>file</c> and <c>node</c> are used for + <c>handler</c>, <c>file</c>, and <c>node</c> are used for information written directly by <c>ttb</c>. </p> - <p>You can add information to the trace information file by - calling <c>write_trace_info/2</c>. Note that <c>ValueList</c> - always will be a list, and if you call <c>write_trace_info/2</c> - several times with the same <c>Key</c>, the <c>ValueList</c> will - be extended with a new value each time. Example: + <p>Information to the trace information file by + can be added by calling + <seealso marker="ttb#write_trace_info/2"><c>ttb:write_trace_info/2</c></seealso>. + Notice that <c>ValueList</c> + always is a list, and if you call <c>write_trace_info/2</c> + many times with the same <c>Key</c>, the <c>ValueList</c> is + extended with a new value each time. </p> + <p><em>Example:</em></p> <p><c>ttb:write_trace_info(mykey,1)</c> gives the entry <c>{mykey,[1]}</c> in <c>TI</c>. Another call, <c>ttb:write_trace_info(mykey,2)</c>, changes this entry to @@ -466,15 +487,15 @@ write_config(Data) -> <p>If you want to limit the size of the trace logs, you can use wrap logs. This works almost like a circular buffer. You can specify the maximum number of binary logs and the maximum size of - each log. <c>ttb</c> will create a new binary log each time a log - reaches the maximum size. When the the maximum number of logs are + each log. <c>ttb</c> then creates a new binary log each time a log + reaches the maximum size. When the maximum number of logs are reached, the oldest log is deleted before a new one is created. </p> - <p>Note that the overall size of data generated by ttb may be greater - than the wrap specification would suggest - if a traced node restarts - and autoresume is enabled, old wrap log is always stored and + <note><p>The overall size of data generated by <c>ttb</c> can be greater + than the wrap specification suggests. If a traced node restarts + and autoresume is enabled, the old wrap log is always stored and a new one is created. - </p> + </p></note> <p>Wrap logs can be formatted one by one or all at once. See <seealso marker="#format">Formatting</seealso>. </p> @@ -484,52 +505,61 @@ write_config(Data) -> <marker id="format"></marker> <title>Formatting</title> <p>Formatting can be done automatically when stopping <c>ttb</c> - (see <seealso marker="#fetch_format">Automatically collect and format logs from all nodes</seealso>), or explicitly by calling - the <c>ttb:format/1/2</c> function. + (see section + <seealso marker="#fetch_format">Automatically Collect and Format Logs from All Nodes</seealso>), or explicitly by calling function + <c>ttb:format/1,2</c>. </p> <p>Formatting means to read a binary log and present it in a readable format. You can use the default format handler in <c>ttb</c> to present each trace message as a line of text, or write your own handler to make more complex interpretations of the - trace information. You can even use the Event Tracer <c>et</c> to - present the trace log graphically (see <seealso marker="#et_viewer">Presenting trace logs with Event Tracer</seealso>). + trace information. You can also use application ET to + present the trace log graphically (see section + <seealso marker="#et_viewer">Presenting Trace Logs with Event Tracer</seealso>). </p> - <p>The first argument to <c>ttb:format/1/2</c> specifies which + <p>The first argument to <c>ttb:format/1,2</c> specifies which binary log(s) to format. This is usually the name of a directory - that ttb created during log fetch. Unless there is the <c>disable_sort</c> - option provided, the logs from different files are always sorted - according to timestamp in traces. + that <c>ttb</c> created during log fetch. Unless option + <c>disable_sort</c> is provided, the logs from different files + are always sorted according to time-stamp in traces. </p> <p>The second argument to <c>ttb:format/2</c> is a list of - options. The <c>out</c> option specifies the destination where the - formatted text shall be written. Default destination is - <c>standard_io</c>, but a filename can also be given. The - <c>handler</c> option specifies the format handler to use. If this - option is not given, the <c>handler</c> option given when starting - the tracer is used. If the <c>handler</c> option was not given - when starting the tracer either, a default handler is used, which - prints each trace message as a line of text. The <c>disable_sort</c> - option indicates that there logs should not be merged according to - timestamp, but processed one file after another (this might be - a bit faster). + options as follows: </p> - <p>A format handler is a fun taking four arguments. This fun will - be called for each trace message in the binary log(s). A simple - example which only prints each trace message could be like this:</p> + <taglist> + <tag><c>out</c></tag> + <item><p>Specifies the destination to write the formatted text. + Default destination is <c>standard_io</c>, but a filename can + also be specified.</p></item> + <tag><c>handler</c></tag> + <item><p>Specifies the format handler to use. If this option is + not specified, option <c>handler</c> that is specified when starting + the tracer is used. If option <c>handler</c> is not specified + when starting the tracer either, a default handler is used, which + prints each trace message as a text line.</p></item> + <tag><c>disable_sort</c></tag> + <item><p>Indicates that the logs are not to be merged according to + time-stamp, but processed one file after another (this can be + a bit faster).</p></item> + </taglist> + <p>A format handler is a fun taking four arguments. This fun is + called for each trace message in the binary log(s). A simple + example that only prints each trace message can be as follows:</p> <code type="none"> fun(Fd, Trace, _TraceInfo, State) -> io:format(Fd, "Trace: ~p~n", [Trace]), State end. </code> - <p><c>Fd</c> is the file descriptor for the destination file, or + <p>Here, <c>Fd</c> is the file descriptor for the destination file, or the atom <c>standard_io</c>. <c>_TraceInfo</c> contains information - from the trace information file (see <seealso marker="#trace_info">Trace Information and the .ti File</seealso>). <c>State</c> is a state variable for the format - handler fun. The initial value of the <c>State</c> variable is - given with the handler option, e.g.</p> + from the trace information file (see section + <seealso marker="#trace_info">Trace Information and File .ti</seealso>). <c>State</c> is a state variable for the format + handler fun. The initial value of variable <c>State</c> is + specified with the handler option, for example:</p> <code type="none"> ttb:format("tiger@durin-ttb", [{handler, {{Mod,Fun}, initial_state}}]) ^^^^^^^^^^^^^ </code> - <p>Another format handler could be used to calculate time spent by + <p>Another format handler can be used to calculate the time spent by the garbage collector:</p> <code type="none"> fun(_Fd,{trace_ts,P,gc_start,_Info,StartTs},_TraceInfo,State) -> @@ -540,111 +570,118 @@ fun(_Fd,{trace_ts,P,gc_start,_Info,StartTs},_TraceInfo,State) -> io:format("GC in process ~w: ~w milliseconds~n", [P,Time]), State -- [{P,StartTs}] end </code> - <p>A more refined version of this format handler is the function - <c>handle_gc/4</c> in the module <c>multitrace.erl</c> which can - be found in the <c>src</c> directory of the Observer application. + <p>A more refined version of this format handler is function + <c>handle_gc/4</c> in module <c>multitrace.erl</c> + included in directory <c>src</c> of the Observer application. </p> - <p>The actual trace message is passed as the second argument (<c>Trace</c>). - The possible values of <c>Trace</c> are:</p> + <p>The trace message is passed as the second argument (<c>Trace</c>). + The possible values of <c>Trace</c> are the following:</p> <list type="bulleted"> - <item>all trace messages described in <c>erlang:trace/3</c> documentation, + <item>All trace messages described in + <seealso marker="erts:erlang#trace/3"><c>erlang:trace/3</c></seealso> </item> - <item><c>{drop, N}</c> if ip tracer is used (see <c>dbg:trace_port/2</c>), + <item><c>{drop, N}</c> if IP tracer is used (see + <seealso marker="runtime_tools:dbg#trace_port/2"><c>dbg:trace_port/2</c></seealso>) </item> - <item><c>end_of_trace</c> received once when all trace messages have - been processed.</item> + <item><c>end_of_trace</c> received once when all trace messages are + processed</item> </list> - <p>By giving the format handler <c>ttb:get_et_handler()</c>, you can have the trace - log presented graphically with <c>et_viewer</c> in the Event - Tracer application (see <seealso marker="#et_viewer">Presenting trace logs with Event Tracer</seealso>). + <p>By giving the format handler + <seealso marker="ttb#get_et_handler/0"><c>ttb:get_et_handler()</c></seealso>, + you can have the trace + log presented graphically with <c>et_viewer</c> in the ET + application (see section + <seealso marker="#et_viewer">Presenting Trace Logs with Event Tracer</seealso>). </p> - <p>You may always decide not to format the whole trace data contained - in the fetch directory, but analyze single files instead. In order - to do so, a single file (or list of files) have to be passed as - the first argument to <c>format/1/2</c>.</p> - <p>Wrap logs can be formatted one by one or all in one go. To - format one of the wrap logs in a set, give the exact name of the - file. To format the whole set of wrap logs, give the name with '*' - instead of the wrap count. An example: + <p>You can always decide not to format the whole trace data contained + in the fetch directory, but analyze single files instead. To do so, + a single file (or list of files) must be passed as the first argument + to <c>format/1,2</c>.</p> + <p>Wrap logs can be formatted one by one or all at once. To + format one of the wrap logs in a set, specify the exact file name. + To format the whole set of wrap logs, specify the name with <c>*</c> + instead of the wrap count. </p> + <p><em>Example:</em></p> <p>Start tracing:</p> - <code type="none"> -(tiger@durin)1> ttb:tracer(node(),{file,{wrap,"trace"}}). + <pre> +(tiger@durin)1> <input>ttb:tracer(node(),{file,{wrap,"trace"}}).</input> {ok,[tiger@durin]} -(tiger@durin)2> ttb:p(...) -... </code> - <p>This will give a set of binary logs, like:</p> +(tiger@durin)2> <input>ttb:p(...)</input> +...</pre> + <p>This gives a set of binary logs, for example:</p> <code type="none"> ... </code> <p>Format the whole set of logs:</p> - <code type="none"> -1> ttb:format("tiger@durin-trace.*.wrp"). + <pre> +1> <input>ttb:format("tiger@durin-trace.*.wrp").</input> .... ok -2> </code> +2> </pre> <p>Format only the first log:</p> - <code type="none"> -1> ttb:format("[email protected]"). + <pre> +1> <input>ttb:format("[email protected]").</input> .... ok -2> </code> +2> </pre> <p>To merge all wrap logs from two nodes:</p> - <code type="none"> -1> ttb:format(["tiger@durin-trace.*.wrp","lion@durin-trace.*.wrp"]). + <pre> +1> <input>ttb:format(["tiger@durin-trace.*.wrp","lion@durin-trace.*.wrp"]).</input> .... ok -2> </code> +2> </pre> <section> <marker id="et_viewer"></marker> - <title>Presenting trace logs with Event Tracer</title> - <p>For detailed information about the Event Tracer, please turn - to the User's Guide and Reference Manuals for the <c>et</c> - application. + <title>Presenting Trace Logs with Event Tracer</title> + <p>For detailed information about the Event Tracer, see the + <seealso marker="et:users_guide">ET</seealso> application. </p> - <p>By giving the format handler <c>ttb:get_et_handler()</c>, you can have the - trace log presented graphically with <c>et_viewer</c> in the - Event Tracer application. <c>ttb</c> provides a few different - filters which can be selected from the Filter menu in the - <c>et_viewer</c> window. The filters are names according to the - type of actors they present (i.e. what each vertical line in the - sequence diagram represent). Interaction between actors is shown - as red arrows between two vertical lines, and activities within - an actor are shown as blue text to the right of the actors line. + <p>By giving the format handler + <seealso marker="ttb#get_et_handler/0"><c>ttb:get_et_handler()</c></seealso>, + you can have the trace log presented graphically with + <c>et_viewer</c> in the ET application. + <c>ttb</c> provides filters that can be selected from the + menu <em>Filter</em> in the <c>et_viewer</c> window. The filters + are names according to the type of actors they present + (that is, what each vertical line in the sequence diagram represents). + Interaction between actors is shown as red arrows between two + vertical lines, and activities within an actor are shown as + blue text to the right of the actors line. </p> - <p>The <c>processes</c> filter is the only filter which will - show all trace messages from a trace log. Each vertical line in + <p>The <c>processes</c> filter is the only filter showing all + trace messages from a trace log. Each vertical line in the sequence diagram represents a process. Erlang messages, - spawn and link/unlink are typical interactions between - processes. Function calls, scheduling and garbage collection are - typical activities within a process. <c>processes</c> is the - default filter. + spawn, and link/unlink are typical interactions between + processes. Function calls, scheduling, and garbage collection, + are typical activities within a process. <c>processes</c> is + the default filter. </p> - <p>The rest of the filters will only show function calls and + <p>The remaining filters only show function calls and function returns. All other trace message are discarded. To get - the most out of these filters, <c>et_viewer</c> needs to known + the most out of these filters, <c>et_viewer</c> must know the caller of each function and the time of return. This can be - obtained by using both the <c>call</c> and <c>return_to</c> - flags when tracing. Note that the <c>return_to</c> flag only - works with local call trace, i.e. when trace patterns are set + obtained using both the <c>call</c> and <c>return_to</c> + flags when tracing. Notice that flag <c>return_to</c> only + works with local call trace, that is, when trace patterns are set with <c>ttb:tpl</c>. </p> - <p>The same result can be obtained by using the <c>call</c> flag - only and setting a match specification like this on local or - global function calls:</p> - <code type="none"> -1> dbg:fun2ms(fun(_) -> return_trace(),message(caller()) end). -[{'_',[],[{return_trace},{message,{caller}}]}] </code> - <p>This should however be done with care, since the - <c>{return_trace}</c> function in the match specification will - destroy tail recursiveness. + <p>The same result can be obtained by using the flag <c>call</c> + only and setting a match specification on local or + global function calls as follows:</p> + <pre> +1> <input>dbg:fun2ms(fun(_) -> return_trace(),message(caller()) end).</input> +[{'_',[],[{return_trace},{message,{caller}}]}]</pre> + <p>This must however be done with care, as function + <c>{return_trace}</c> in the match specification + destroys tail recursiveness. </p> <p>The <c>modules</c> filter shows each module as a vertical line in the sequence diagram. External function calls/returns - are shown as interactions between modules and internal function + are shown as interactions between modules, and internal function calls/returns are shown as activities within a module. </p> <p>The <c>functions</c> filter shows each function as a vertical @@ -655,9 +692,9 @@ ok <p>The <c>mods_and_procs</c> and <c>funcs_and_procs</c> filters are equivalent to the <c>modules</c> and <c>functions</c> filters respectively, except that each module or function can - have several vertical lines, one for each process it resides on. + have many vertical lines, one for each process it resides on. </p> - <p>In the next example, modules <c>foo</c> and <c>bar</c> are used:</p> + <p>In the following example, modules <c>foo</c> and <c>bar</c> are used:</p> <code type="none"> -module(foo). -export([start/0,go/0]). @@ -672,8 +709,9 @@ go() -> go -> bar:f1(), go() - end. -</code><code type="none"> + end.</code> + +<code type="none"> -module(bar). -export([f1/0,f3/0]). f1() -> @@ -684,57 +722,56 @@ f2() -> f3() -> ok.</code> - <p>Now let's set up the trace.</p> -<code> -(tiger@durin)1>%%First we retrieve the Pid to limit traced processes set -(tiger@durin)1>Pid = foo:start(). -(tiger@durin)2>%%Now we set up tracing -(tiger@durin)2>ttb:tracer(). -(tiger@durin)3>ttb:p(Pid, [call, return_to, procs, set_on_spawn]). -(tiger@durin)4>ttb:tpl(bar, []). -(tiger@durin)5>%%Invoke our test function and see output with et viewer -(tiger@durin)5>Pid ! go. -(tiger@durin)6>ttb:stop({format, {handler, ttb:get_et_handler()}}). -</code> - - <p>This shoud render a result similar to the - following: + <p>Setting up the trace:</p> +<pre> +(tiger@durin)1> %%First we retrieve the Pid to limit traced processes set +(tiger@durin)1> <input>Pid = foo:start().</input> +(tiger@durin)2> %%Now we set up tracing +(tiger@durin)2> <input>ttb:tracer().</input> +(tiger@durin)3> <input>ttb:p(Pid, [call, return_to, procs, set_on_spawn]).</input> +(tiger@durin)4> <input>ttb:tpl(bar, []).</input> +(tiger@durin)5> %%Invoke our test function and see output with et viewer +(tiger@durin)5> <input>Pid ! go.</input> +(tiger@durin)6> <input>ttb:stop({format, {handler, ttb:get_et_handler()}}).</input></pre> + + <p>This renders a result similar to the following: </p> - <p></p> <image file="et_processes.gif"> <icaption>Filter: "processes"</icaption> </image> + <p></p> <image file="et_modsprocs.gif"> <icaption>Filter: "mods_and_procs"</icaption> </image> - <p>Note, that we can use <c>ttb:start_trace/4</c> function to help - us here:</p> -<code> -(tiger@durin)1>Pid = foo:start(). -(tiger@durin)2>ttb:start_trace([node()], - [{bar,[]}], - {Pid, [call, return_to, procs, set_on_spawn]} - {handler, ttb:get_et_handler()}). -(tiger@durin)3>Pid ! go. -(tiger@durin)4>ttb:stop(format). -</code> + <p>Notice that function + <seealso marker="ttb#start_trace/4"><c>ttb:start_trace/4</c></seealso> + can be used as help as follows:</p> +<pre> +(tiger@durin)1> <input>Pid = foo:start().</input> +(tiger@durin)2> <input>ttb:start_trace([node()], + [{bar,[]}], + {Pid, [call, return_to, procs, set_on_spawn]} + {handler, ttb:get_et_handler()}).</input> +(tiger@durin)3> <input>Pid ! go.</input> +(tiger@durin)4> <input>ttb:stop(format).</input></pre> </section> </section> <section> <marker id="fetch_format"></marker> - <title>Automatically collect and format logs from all nodes</title> - <p>By default <c>ttb:stop/1</c> fetches trace logs and - trace information files from all nodes. The logs are stored in a - new directory named <c>ttb_upload-Filename-Timestamp</c> under the working - directory of the trace control node. Fetching may be disabled by - providing the <c>nofetch</c> option to <c>ttb:stop/1</c>. User can - specify a fetch directory of his choice passing the - <c>{fetch_dir, Dir}</c> option. + <title>Automatically Collect and Format Logs from All Nodes</title> + <p>By default, + + <seealso marker="ttb#stop/1"><c>ttb:stop/1</c></seealso> fetches trace logs + and trace information files from all nodes. The logs are stored in a + new directory named <c>ttb_upload-Filename-Timestamp</c> under the + working directory of the trace control node. Fetching can be disabled + by providing option <c>nofetch</c> to <c>ttb:stop/1</c>. The user can + specify a fetch directory by passing option <c>{fetch_dir, Dir}</c>. </p> - <p>If the option <c>format</c> is given to <c>ttb:stop/1</c>, the + <p>If option <c>format</c> is specified to <c>ttb:stop/1</c>, the trace logs are automatically formatted after tracing is stopped. </p> @@ -742,117 +779,122 @@ f3() -> <section> <title>History and Configuration Files</title> - <p>For the tracing functionality, <c>dbg</c> could be used instead - of the <c>ttb</c> for setting trace flags on processes and trace - patterns for call trace, i.e. the functions <c>p</c>, <c>tp</c>, - <c>tpl</c>, <c>ctp</c>, <c>ctpl</c> and <c>ctpg</c>. There are only - two things added by <c>ttb</c> for these functions: + <p>For the tracing functionality, + <seealso marker="runtime_tools:dbg"><c>dbg</c></seealso> + can be used instead + of <c>ttb</c> for setting trace flags on processes and trace + patterns for call trace, that is, the functions + <c>p</c>, <c>tp</c>, <c>tpl</c>, <c>ctp</c>, <c>ctpl</c>, and <c>ctpg</c>. Only the + following two things are added by <c>ttb</c> for these functions:</p> <list type="bulleted"> - <item>all calls are stored in the history buffer and can be + <item>All calls are stored in the history buffer and can be recalled and stored in a configuration file. This makes it - easy to setup the same trace environment e.g. if you want to - compare two test runs. It also reduces the amount of - typing when using <c>ttb</c> from the erlang shell;</item> - <item>shortcuts are provided for the most common match - specifications (in order not to force the user to use - <c>dbg:fun2ms</c> continually</item>). + easy to set up the same trace environment, for example, if you + want to compare two test runs. It also reduces the amount of + typing when using <c>ttb</c> from the Erlang shell.</item> + <item>Shortcuts are provided for the most common match + specifications (to not force you to use + <seealso marker="runtime_tools:dbg#fun2ms/1"><c>dbg:fun2ms</c></seealso> + continually).</item> </list> - </p> - <p>Use <c>list_history/0</c> to see the content of the history - buffer, and <c>run_history/1</c> to re-execute one of the entries. + <p>Use + <seealso marker="ttb#list_history/0"><c>ttb:list_history/0</c></seealso> + to see the content of the history buffer and + <seealso marker="ttb#run_history/1"><c>ttb:run_history/1</c></seealso> + to re-execute one of the entries. </p> <p>The main purpose of the history buffer is the possibility to create configuration files. Any function stored in the history buffer can be written to a configuration file and used for - creating a specific configuration at any time with one single + creating a specific configuration at any time with a single function call. </p> <p>A configuration file is created or extended with - <c>write_config/2/3</c>. Configuration files are binary files + <seealso marker="ttb#write_config/2"><c>ttb:write_config/2,3</c></seealso>. + Configuration files are binary files and can therefore only be read and written with functions provided by <c>ttb</c>. </p> - <p>You can write the complete content of the history buffer to a - config file by calling - <c>ttb:write_config(ConfigFile,all)</c>. And you can write - selected entries from the history by calling + <p>The complete content of the history buffer can be written to a + configuration file by calling + <c>ttb:write_config(ConfigFile,all)</c>. Selected entries from + the history can be written by calling <c>ttb:write_config(ConfigFile,NumList)</c>, where <c>NumList</c> is a list of integers pointing out the history entries to write. Moreover, the history buffer is always dumped - to <c>ttb_last_config</c> when <c>ttb:stop/0/1</c> is called. + to <c>ttb_last_config</c> when <c>ttb:stop/0,1</c> is called. </p> - <p>User defined entries can also be written to a config file by - calling the function - <c>ttb:write_config(ConfigFile,ConfigList)</c> where + <p>User-defined entries can also be written to a configuration file + by calling function + <c>ttb:write_config(ConfigFile,ConfigList)</c>, where <c>ConfigList</c> is a list of <c>{Module,Function,Args}</c>. </p> <p>Any existing file <c>ConfigFile</c> is deleted and a new file - is created when <c>write_config/2</c> is called. The option - <c>append</c> can be used if you wish to add something at the end - of an existing config file, e.g. + is created when <c>write_config/2</c> is called. Option + <c>append</c> can be used to add something at the end + of an existing configuration file, for example, <c>ttb:write_config(ConfigFile,What,[append])</c>. </p> - <section> - <title>Example: History and configuration files</title> - <p>See the content of the history buffer</p> - <code type="none"><![CDATA[ -(tiger@durin)191> ttb:tracer(). + <p><em>Example:</em></p> + <p>See the content of the history buffer:</p> + <pre> +(tiger@durin)191> <input>ttb:tracer().</input> {ok,[tiger@durin]} -(tiger@durin)192> ttb:p(self(),[garbage_collection,call]). -{ok,{[<0.1244.0>],[garbage_collection,call]}} -(tiger@durin)193> ttb:tp(ets,new,2,[]). +(tiger@durin)192> <input>ttb:p(self(),[garbage_collection,call]).</input> +{ok,{[<0.1244.0>],[garbage_collection,call]}} +(tiger@durin)193> <input>ttb:tp(ets,new,2,[]).</input> {ok,[{matched,1}]} -(tiger@durin)194> ttb:list_history(). +(tiger@durin)194> <input>ttb:list_history().</input> [{1,{ttb,tracer,[tiger@durin,[]]}}, - {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, - {3,{ttb,tp,[ets,new,2,[]]}}] ]]></code> + {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, + {3,{ttb,tp,[ets,new,2,[]]}}]</pre> <p>Execute an entry from the history buffer:</p> - <code type="none"><![CDATA[ -(tiger@durin)195> ttb:ctp(ets,new,2). + <pre> +(tiger@durin)195> <input>ttb:ctp(ets,new,2).</input> {ok,[{matched,1}]} -(tiger@durin)196> ttb:list_history(). +(tiger@durin)196> <input>ttb:list_history().</input> [{1,{ttb,tracer,[tiger@durin,[]]}}, - {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, + {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, {3,{ttb,tp,[ets,new,2,[]]}}, {4,{ttb,ctp,[ets,new,2]}}] -(tiger@durin)197> ttb:run_history(3). +(tiger@durin)197> <input>ttb:run_history(3).</input> ttb:tp(ets,new,2,[]) -> -{ok,[{matched,1}]} ]]></code> +{ok,[{matched,1}]}</pre> <p>Write the content of the history buffer to a configuration file:</p> - <code type="none"><![CDATA[ -(tiger@durin)198> ttb:write_config("myconfig",all). + <pre> +(tiger@durin)198> <input>ttb:write_config("myconfig",all).</input> ok -(tiger@durin)199> ttb:list_config("myconfig"). +(tiger@durin)199> <input>ttb:list_config("myconfig").</input> [{1,{ttb,tracer,[tiger@durin,[]]}}, - {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, + {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, {3,{ttb,tp,[ets,new,2,[]]}}, {4,{ttb,ctp,[ets,new,2]}}, - {5,{ttb,tp,[ets,new,2,[]]}}] ]]></code> + {5,{ttb,tp,[ets,new,2,[]]}}]</pre> <p>Extend an existing configuration:</p> - <code type="none"><![CDATA[ -(tiger@durin)200> ttb:write_config("myconfig",[{ttb,tp,[ets,delete,1,[]]}], -[append]). + <pre> +(tiger@durin)200> <input>ttb:write_config("myconfig",[{ttb,tp,[ets,delete,1,[]]}], +[append]).</input> ok -(tiger@durin)201> ttb:list_config("myconfig"). +(tiger@durin)201> <input>ttb:list_config("myconfig").</input> [{1,{ttb,tracer,[tiger@durin,[]]}}, - {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, + {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, {3,{ttb,tp,[ets,new,2,[]]}}, {4,{ttb,ctp,[ets,new,2]}}, {5,{ttb,tp,[ets,new,2,[]]}}, - {6,{ttb,tp,[ets,delete,1,[]]}}] ]]></code> + {6,{ttb,tp,[ets,delete,1,[]]}}]</pre> <p>Go back to a previous configuration after stopping Trace Tool Builder:</p> - <code type="none"><![CDATA[ -(tiger@durin)202> ttb:stop(). + <pre> +(tiger@durin)202> <input>ttb:stop().</input> ok -(tiger@durin)203> ttb:run_config("myconfig"). +(tiger@durin)203> <input>ttb:run_config("myconfig").</input> ttb:tracer(tiger@durin,[]) -> {ok,[tiger@durin]} -ttb:p(<0.1244.0>,[garbage_collection,call]) -> -{ok,{[<0.1244.0>],[garbage_collection,call]}} +ttb:p(<0.1244.0>,[garbage_collection,call]) -> +{ok,{[<0.1244.0>],[garbage_collection,call]}} ttb:tp(ets,new,2,[]) -> {ok,[{matched,1}]} @@ -866,133 +908,135 @@ ttb:tp(ets,new,2,[]) -> ttb:tp(ets,delete,1,[]) -> {ok,[{matched,1}]} -ok ]]></code> +ok</pre> <p>Write selected entries from the history buffer to a configuration file:</p> - <code type="none"><![CDATA[ -(tiger@durin)204> ttb:list_history(). + <pre> +(tiger@durin)204> <input>ttb:list_history().</input> [{1,{ttb,tracer,[tiger@durin,[]]}}, - {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, + {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, {3,{ttb,tp,[ets,new,2,[]]}}, {4,{ttb,ctp,[ets,new,2]}}, {5,{ttb,tp,[ets,new,2,[]]}}, {6,{ttb,tp,[ets,delete,1,[]]}}] -(tiger@durin)205> ttb:write_config("myconfig",[1,2,3,6]). +(tiger@durin)205> <input>ttb:write_config("myconfig",[1,2,3,6]).</input> ok -(tiger@durin)206> ttb:list_config("myconfig"). +(tiger@durin)206> <input>ttb:list_config("myconfig").</input> [{1,{ttb,tracer,[tiger@durin,[]]}}, - {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, + {2,{ttb,p,[<0.1244.0>,[garbage_collection,call]]}}, {3,{ttb,tp,[ets,new,2,[]]}}, {4,{ttb,tp,[ets,delete,1,[]]}}] -(tiger@durin)207> ]]></code> - </section> +(tiger@durin)207></pre> </section> <section> <title>Sequential Tracing</title> <p>To learn what sequential tracing is and how it can be used, - please turn to the reference manual for the - <em><c>seq_trace</c></em> module in the <em><c>kernel</c></em> - application. + see the Reference Manual for + <seealso marker="kernel:seq_trace"><c>seq_trace</c></seealso>. </p> - <p>The support for sequential tracing provided by the Trace Tool - Builder includes </p> + <p>The support for sequential tracing provided by Trace Tool + Builder includes the following:</p> <list type="bulleted"> <item>Initiation of the system tracer. This is automatically - done when a trace port is started with <c>ttb:tracer/0/1/2</c></item> - <item>Creation of match specifications which activates - sequential tracing</item> + done when a trace port is started with + <seealso marker="ttb#tracer/0"><c>ttb:tracer/0,1,2</c></seealso>.</item> + <item>Creation of match specifications that activates + sequential tracing.</item> </list> - <p>Starting sequential tracing requires that a tracer has been - started with the <c>ttb:tracer/0/1/2</c> function. Sequential - tracing can then either be started via a trigger function with a - match specification created with <c>ttb:seq_trigger_ms/0/1</c>, - or directly by using the <c>seq_trace</c> module in the - <c>kernel</c> application. + <p>Starting sequential tracing requires that a tracer is + started with function <c>ttb:tracer/0,1,2</c>. Sequential + tracing can then be started in either of the following ways: </p> + <list type="bulleted"> + <item>Through a trigger function with a match specification + created with + <seealso marker="ttb#seq_trigger_ms/0"><c>ttb:seq_trigger_ms/0,1</c></seealso>.</item> + <item>Directly by using module + <seealso marker="kernel:seq_trace"><c>seq_trace</c></seealso>.</item> + </list> - <section> - <title>Example: Sequential tracing</title> - <p>In the following example, the function + <p><em>Example 1:</em></p> + <p>In the following example, function <c>dbg:get_tracer/0</c> is used as trigger for sequential tracing:</p> - <code type="none"><![CDATA[ -(tiger@durin)110> ttb:tracer(). + <pre> +(tiger@durin)110> <input>ttb:tracer().</input> {ok,[tiger@durin]} -(tiger@durin)111> ttb:p(self(),call). -{ok,{[<0.158.0>],[call]}} -(tiger@durin)112> ttb:tp(dbg,get_tracer,0,ttb:seq_trigger_ms(send)). +(tiger@durin)111> <input>ttb:p(self(),call).</input> +{ok,{[<0.158.0>],[call]}} +(tiger@durin)112> <input>ttb:tp(dbg,get_tracer,0,ttb:seq_trigger_ms(send)).</input> {ok,[{matched,1},{saved,1}]} -(tiger@durin)113> dbg:get_tracer(), seq_trace:reset_trace(). +(tiger@durin)113> <input>dbg:get_tracer(), seq_trace:reset_trace().</input> true -(tiger@durin)114> ttb:stop(format). -({<0.158.0>,{shell,evaluator,3},tiger@durin}) call dbg:get_tracer() -SeqTrace [0]: ({<0.158.0>,{shell,evaluator,3},tiger@durin}) -{<0.237.0>,dbg,tiger@durin} ! {<0.158.0>,{get_tracer,tiger@durin}} +(tiger@durin)114> <input>ttb:stop(format).</input> +({<0.158.0>,{shell,evaluator,3},tiger@durin}) call dbg:get_tracer() +SeqTrace [0]: ({<0.158.0>,{shell,evaluator,3},tiger@durin}) +{<0.237.0>,dbg,tiger@durin} ! {<0.158.0>,{get_tracer,tiger@durin}} [Serial: {0,1}] -SeqTrace [0]: ({<0.237.0>,dbg,tiger@durin}) -{<0.158.0>,{shell,evaluator,3},tiger@durin} ! {dbg,{ok,#Port<0.222>}} +SeqTrace [0]: ({<0.237.0>,dbg,tiger@durin}) +{<0.158.0>,{shell,evaluator,3},tiger@durin} ! {dbg,{ok,#Port<0.222>}} [Serial: {1,2}] ok -(tiger@durin)116> ]]></code> - <p>Starting sequential tracing with a trigger is actually more +(tiger@durin)116></pre> + <p><em>Example 2:</em></p> + <p>Starting sequential tracing with a trigger is more useful if the trigger function is not called directly from the shell, but rather implicitly within a larger system. When calling a function from the shell, it is simpler to start - sequential tracing directly, e.g.</p> - <code type="none"><![CDATA[ -(tiger@durin)116> ttb:tracer(). + sequential tracing directly, for example, as follows:</p> + <pre> +(tiger@durin)116> <input>ttb:tracer().</input> {ok,[tiger@durin]} -(tiger@durin)117> seq_trace:set_token(send,true), dbg:get_tracer(), -seq_trace:reset_trace(). +(tiger@durin)117> <input>seq_trace:set_token(send,true), dbg:get_tracer(), +seq_trace:reset_trace().</input> true -(tiger@durin)118> ttb:stop(format). -SeqTrace [0]: ({<0.158.0>,{shell,evaluator,3},tiger@durin}) -{<0.246.0>,dbg,tiger@durin} ! {<0.158.0>,{get_tracer,tiger@durin}} +(tiger@durin)118> <input>ttb:stop(format).</input> +SeqTrace [0]: ({<0.158.0>,{shell,evaluator,3},tiger@durin}) +{<0.246.0>,dbg,tiger@durin} ! {<0.158.0>,{get_tracer,tiger@durin}} [Serial: {0,1}] -SeqTrace [0]: ({<0.246.0>,dbg,tiger@durin}) -{<0.158.0>,{shell,evaluator,3},tiger@durin} ! {dbg,{ok,#Port<0.229>}} +SeqTrace [0]: ({<0.246.0>,dbg,tiger@durin}) +{<0.158.0>,{shell,evaluator,3},tiger@durin} ! {dbg,{ok,#Port<0.229>}} [Serial: {1,2}] ok -(tiger@durin)120> ]]></code> - <p>In both examples above, the <c>seq_trace:reset_trace/0</c> - resets the trace token immediately after the traced function in - order to avoid lots of trace messages due to the printouts in - the erlang shell. +(tiger@durin)120></pre> + <p>In both previous examples, <c>seq_trace:reset_trace/0</c> + resets the trace token immediately after the traced function + to avoid many trace messages because of the printouts in + the Erlang shell. </p> - <p>All functions in the <c>seq_trace</c> module, except - <c>set_system_tracer/1</c>, can be used after the trace port has - been started with <c>ttb:tracer/0/1/2</c>. + <p>All functions in module <c>seq_trace</c>, except + <c>set_system_tracer/1</c>, can be used after the trace port + is started with <c>ttb:tracer/0,1,2</c>. </p> - </section> </section> <section> - <title>Example: Multipurpose trace tool</title> - <p>The module <c>multitrace.erl</c> which can be found in the - <c>src</c> directory of the Observer application implements a + <title>Multipurpose Trace Tool</title> + <p>Module <c>multitrace</c> in + directory <c>src</c> of the Observer application provides a small tool with three possible trace settings. The trace messages - are written to binary files which can be formatted with the - function <em><c>multitrace:format/1/2</c></em>. + are written to binary files, which can be formatted with + function <c>multitrace:format/1,2</c>: </p> <taglist> - <tag><em><c>multitrace:debug(What)</c></em></tag> - <item>Start calltrace on all processes and trace the given + <tag><c>multitrace:debug(What)</c></tag> + <item><p>Start calltrace on all processes and trace the specified function(s). The format handler used is - <c>multitrace:handle_debug/4</c> which prints each call and - return. <c>What</c> must be an item or a list of items to trace, - given on the format <c>{Module,Function,Arity}</c>, - <c>{Module,Function}</c> or just <c>Module</c>.</item> - <tag><em><c>multitrace:gc(Procs)</c></em></tag> - <item>Trace garbage collection on the given process(es). The - format handler used is <c>multitrace:handle_gc/4</c> which - prints start and stop and the time spent for each GC.</item> - <tag><em><c>multitrace:schedule(Procs)</c></em></tag> - <item>Trace in- and out-scheduling on the given process(es). The - format handler used is <c>multitrace:handle_schedule/4</c> which - prints each in and out scheduling with process, timestamp and + <c>multitrace:handle_debug/4</c> that prints each call and + returns. <c>What</c> must be an item or a list of items to trace, + specified on the format <c>{Module,Function,Arity}</c>, + <c>{Module,Function}</c>, or only <c>Module</c>.</p></item> + <tag><c>multitrace:gc(Procs)</c></tag> + <item><p>Trace garbage collection on the specified process(es). The + format handler used is <c>multitrace:handle_gc/4</c> that + prints start, stop, and the time spent for each garbage collection.</p></item> + <tag><c>multitrace:schedule(Procs)</c></tag> + <item><p>Trace in-scheduling and out-scheduling on the specified process(es). + The format handler used is <c>multitrace:handle_schedule/4</c> that + prints each in-scheduling and out-scheduling with process, time-stamp, and current function. It also prints the total time each traced - process was scheduled in.</item> + process was scheduled in.</p></item> </taglist> </section> </chapter> |