diff options
Diffstat (limited to 'lib/inviso/doc/src/inviso_lfm.xml')
| -rw-r--r-- | lib/inviso/doc/src/inviso_lfm.xml | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/lib/inviso/doc/src/inviso_lfm.xml b/lib/inviso/doc/src/inviso_lfm.xml new file mode 100644 index 0000000000..02e012f2ea --- /dev/null +++ b/lib/inviso/doc/src/inviso_lfm.xml @@ -0,0 +1,93 @@ +<?xml version="1.0" encoding="latin1" ?> +<!DOCTYPE erlref SYSTEM "erlref.dtd"> + +<erlref> + <header> + <copyright> + <year>2006</year> + <year>2007</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. + + The Initial Developer of the Original Code is Ericsson AB. + </legalnotice> + + <title>inviso_lfm</title> + <prepared></prepared> + <docno></docno> + <date></date> + <rev></rev> + </header> + <module>inviso_lfm</module> + <modulesummary>An Inviso Off-Line Logfile Merger</modulesummary> + <description> + <p>Implements an off-line logfile merger, merging binary trace-log files from several nodes together in chronological order. The logfile merger can also do pid-to-alias translations.</p> + <p>The logfile merger is supposed to be called from the Erlang shell or a higher layer trace tool. For it to work, all logfiles and trace information files (containing the pid-alias associations) must be located in the file system accessible from this node and organized according to the API description.</p> + <p>The logfile merger starts a process, the output process, which in its turn starts one reader process for every node it shall merge logfiles from. Note that the reason for a process for each node is not remote communication, the logfile merger is an off-line utility, it is to sort the logfile entries in chronological order.</p> + <p>The logfile merger can be customized both when it comes to the implementation of the reader processes and the output the output process shall generate for every logfile entry.</p> + </description> + <funcs> + <func> + <name>merge(Files, OutFile) -></name> + <name>merge(Files, WorkHFun, InitHandlerData) -></name> + <name>merge(Files, BeginHFun, WorkHFun, EndHFun, InitHandlerData) -> {ok, Count} | {error, Reason}</name> + <fsummary>Merge logfiles into one file in chronological order</fsummary> + <type> + <v>Files = [FileDescription]</v> + <v> FileDescription = FileSet | {reader,RMod,RFunc,FileSet}</v> + <v> FileSet = {Node,LogFiles} | {Node,[LogFiles]}</v> + <v> Node = atom()</v> + <v> LogFiles = [{trace_log,[FileName]}] | [{trace_log,[FileName]},{ti_log,TiFileSpec}]</v> + <v> TiFileSpec = [string()] - a list of one string.</v> + <v> FileName = string()</v> + <v> RMod = RFunc = atom()</v> + <v>OutFile = string()</v> + <v>BeginHFun = fun(InitHandlerData) -> {ok, NewHandlerData} | {error, Reason}</v> + <v>WorkHFun = fun(Node, LogEntry, PidMappings, HandlerData) -> {ok, NewHandlerData}</v> + <v> LogEntry = tuple()</v> + <v> PidMappings = term()</v> + <v>EndHFun = fun(HandlerData) -> ok | {error, Reason}</v> + <v>Count = int()</v> + <v>Reason = term()</v> + </type> + <desc> + <p>Merges the logfiles in <c>Files</c> together into one file in chronological order. The logfile merger consists of an output process and one or several reader processes.</p> + <p>Returns <c>{ok, Count}</c> where <c>Count</c> is the total number of log entries processed, if successful.</p> + <p>When specifying <c>LogFiles</c>, currently the standard reader-process only supports:</p> + <list type="bulleted"> + <item>one single file</item> + <item>a list of wraplog files, following the naming convention <c><![CDATA[<Prefix><Nr><Suffix>]]></c>.</item> + </list> + <p>Note that (when using the standard reader process) it is possible to give a list of <c>LogFiles</c>. The list must be sorted starting with the oldest. This will cause several trace-logs (from the same node) to be merged together in the same <c>OutFile</c>. The reader process will simply start reading the next file (or wrapset) when the previous is done.</p> + <p><c>FileDescription == {reader,RMod,RFunc,FileSet}</c> indicates that <c>spawn(RMod, RFunc, [OutputPid,LogFiles])</c> shall create a reader process.</p> + <p>The output process is customized with <c>BeginHFun</c>, <c>WorkHFun</c> and <c>EndHFun</c>. If using <c>merge/2</c> a default output process configuration is used, basically creating a text file and writing the output line by line. <c>BeginHFun</c> is called once before requesting log entries from the reader processes. <c>WorkHFun</c> is called for every log entry (trace message) <c>LogEntry</c>. Here the log entry typically gets written to the output. <c>PidMappings</c> is the translations produced by the reader process. <c>EndHFun</c> is called when all reader processes have terminated.</p> + <p>Currently the standard reader can only handle one ti-file (per <c>LogFiles</c>). The current inviso meta tracer is further not capable of wrapping ti-files. (This also because a wrapped ti-log will most likely be worthless since alias associations done in the beginning are erased but still used in the trace-log).</p> + <p>The standard reader process is implemented in the module <c>inviso_lfm_tpreader</c> (trace port reader). It understands Erlang linked in trace-port driver generated trace-logs and <c>inviso_rt_meta</c> generated trace information files.</p> + </desc> + </func> + </funcs> + + <section> + <title>Writing Your Own Reader Process</title> + <p>Writing a reader process is not that difficult. It must:</p> + <list type="bulleted"> + <item>Export an init-like function accepting two arguments, pid of the output process and the <c>LogFiles</c> component. <c>LogFiles</c> is actually only used by the reader processes, making it possible to redefine <c>LogFiles</c> if implementing an own reader process.</item> + <item>Respond to <c>{get_next_entry, OutputPid}</c> messages with <c>{next_entry, self(), PidMappings, NowTimeStamp, Term}</c> or <c>{next_entry, self(), {error,Reason}}</c>.</item> + <item>Terminate normally when no more log entries are available.</item> + <item>Terminate on an incoming EXIT-signal from <c>OutputPid</c>.</item> + </list> + <p>The reader process must of course understand the format of a logfile written by the runtime component.</p> + </section> +</erlref> + |