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diff --git a/lib/tools/doc/src/instrument.xml b/lib/tools/doc/src/instrument.xml
index bb6f9b6100..9fd9332373 100644
--- a/lib/tools/doc/src/instrument.xml
+++ b/lib/tools/doc/src/instrument.xml
@@ -4,7 +4,7 @@
<erlref>
<header>
<copyright>
- <year>1998</year><year>2016</year>
+ <year>1998</year><year>2018</year>
<holder>Ericsson AB. All Rights Reserved.</holder>
</copyright>
<legalnotice>
@@ -41,387 +41,190 @@
<note>
<p>Note that this whole module is experimental, and the representations
used as well as the functionality is likely to change in the future.</p>
- <p>The <c>instrument</c> module interface was slightly changed in
- Erlang/OTP R9C.</p>
</note>
- <p>To start an Erlang runtime system with instrumentation, use the
- <c>+Mi*</c> set of command-line arguments to the <c>erl</c> command (see
- the erts_alloc(3) and erl(1) man pages).</p>
- <p>The basic object of study in the case of memory allocation is a memory
- allocation map. A memory allocation map contains a list of descriptors
- for each allocated memory block. Currently, a descriptor is a 4-tuple</p>
- <pre>
- {TypeNo, Address, Size, PidDesc} </pre>
- <p>where <c>TypeNo</c> is the memory block type number, <c>Address</c>
- is its place in memory, and <c>Size</c> is its size, in bytes.
- <c>PidDesc</c> is either a tuple <c>{X,Y,Z}</c> identifying the
- process which was executing when the block was allocated, or
- <c>undefined</c> if no process was executing. The pid tuple
- <c>{X,Y,Z}</c> can be transformed into a real pid by usage of the
- <c>c:pid/3</c> function.</p>
- <p>Various details about memory allocation:</p>
- <p>Memory blocks are allocated both on the heap segment and on other memory
- segments. This can cause the instrumentation functionality to report
- very large holes. Currently the instrumentation functionality doesn't
- provide any support for distinguishing between holes between memory
- segments, and holes between allocated blocks inside memory segments.
- The current size of the process cannot be obtained from within Erlang,
- but can be seen with one of the system statistics tools, e.g.,
- <c>ps</c> or <c>top</c>. The Solaris utility <c>pmap</c> can be
- useful. It reports currently mapped memory segments. </p>
- <p>Overhead for instrumentation: When the emulator has been started with
- the <seealso marker="erts:erts_alloc#Mim">"+Mim true"</seealso>
- flag, each block is preceded by a 24 bytes large
- header on a 32-bit machine and a 48 bytes large header on a 64-bit
- machine. When the emulator has been started with the
- <seealso marker="erts:erts_alloc#Mis">"+Mis true"</seealso>
- flag, each block is preceded by an 8 bytes large header. These are the header
- sizes used by the Erlang 5.3/OTP R9C emulator. Other versions of the
- emulator may use other header sizes. The function
- <seealso marker="#block_header_size/1">block_header_size/1</seealso>
- can be used for retrieving the header size used for a specific memory
- allocation map. The time overhead for managing the instrumentation
- data is small.</p>
- <p>Sizes presented by the instrumentation functionality are (by the
- emulator) requested sizes, i.e. neither instrumentation headers nor
- headers used by allocators are included.</p>
</description>
+ <datatypes>
+ <datatype>
+ <name name="block_histogram"/>
+ <desc>
+ <p>A histogram of block sizes where each interval's upper bound is
+ twice as high as the one before it.</p>
+ <p>The upper bound of the first interval is provided by the function
+ that returned the histogram, and the last interval has no upper
+ bound.</p>
+ </desc>
+ </datatype>
+ <datatype>
+ <name name="allocation_summary"/>
+ <desc>
+ <p>A summary of allocated block sizes (including their headers) grouped
+ by their <c><anno>Origin</anno></c> and <c><anno>Type</anno></c>.</p>
+ <p><c><anno>Origin</anno></c> is generally which NIF or driver that
+ allocated the blocks, or 'system' if it could not be determined.</p>
+ <p><c><anno>Type</anno></c> is the allocation category that the blocks
+ belong to, e.g. <c>db_term</c>, <c>message</c> or <c>binary</c>.</p>
+ <p>If one or more carriers could not be scanned in full without harming
+ the responsiveness of the system, <c><anno>UnscannedSize</anno></c>
+ is the number of bytes that had to be skipped.</p>
+ </desc>
+ </datatype>
+ <datatype>
+ <name name="carrier_info_list"/>
+ <desc>
+ <p><c><anno>AllocatorType</anno></c> is the type of the allocator that
+ employs this carrier.</p>
+ <p><c><anno>TotalSize</anno></c> is the total size of the carrier,
+ including its header.</p>
+ <p><c><anno>AllocatedSize</anno></c> is the combined size of the
+ carrier's allocated blocks, including their headers.</p>
+ <p><c><anno>AllocatedCount</anno></c> is the number of allocated
+ blocks in the carrier.</p>
+ <p><c><anno>InPool</anno></c> is whether the carrier is in the
+ migration pool.</p>
+ <p><c><anno>FreeBlocks</anno></c> is a histogram of the free block
+ sizes in the carrier.</p>
+ <p>If the carrier could not be scanned in full without harming the
+ responsiveness of the system, <c><anno>UnscannedSize</anno></c> is
+ the number of bytes that had to be skipped.</p>
+ </desc>
+ </datatype>
+ </datatypes>
<funcs>
+
<func>
- <name>allocator_descr(MemoryData, TypeNo) -> AllocDescr | invalid_type | "unknown"</name>
- <fsummary>Returns a allocator description</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- <v>TypeNo = int()</v>
- <v>AllocDescr = atom() | string()</v>
- </type>
- <desc>
- <p>Returns the allocator description of the allocator that
- manages memory blocks of type number <c>TypeNo</c> used in
- <c>MemoryData</c>.
- Valid <c>TypeNo</c>s are in the range returned by
- <seealso marker="#type_no_range/1">type_no_range/1</seealso> on
- this specific memory allocation map. If <c>TypeNo</c> is an
- invalid integer, <c>invalid_type</c> is returned.</p>
- </desc>
- </func>
- <func>
- <name>block_header_size(MemoryData) -> int()</name>
- <fsummary>Returns the memory block header size used by the emulator that generated the memory allocation map</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- </type>
- <desc>
- <marker id="block_header_size_1"></marker>
- <p>Returns the memory block header size used by the
- emulator that generated the memory allocation map. The block
- header size may differ between different emulators.</p>
- </desc>
- </func>
- <func>
- <name>class_descr(MemoryData, TypeNo) -> ClassDescr | invalid_type | "unknown"</name>
- <fsummary>Returns a allocator description</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- <v>TypeNo = int()</v>
- <v>ClassDescr = atom() | string()</v>
- </type>
- <desc>
- <p>Returns the class description of the class that
- the type number <c>TypeNo</c> used in <c>MemoryData</c> belongs
- to.
- Valid <c>TypeNo</c>s are in the range returned by
- <seealso marker="#type_no_range/1">type_no_range/1</seealso> on
- this specific memory allocation map. If <c>TypeNo</c> is an
- invalid integer, <c>invalid_type</c> is returned.</p>
- </desc>
- </func>
- <func>
- <name>descr(MemoryData) -> DescrMemoryData</name>
- <fsummary>Replace type numbers in memory allocation map with type descriptions</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- <v>DescrMemoryData = {term(), DescrAllocList}</v>
- <v>DescrAllocList = [DescrDesc]</v>
- <v>DescrDesc = {TypeDescr, int(), int(), DescrPidDesc}</v>
- <v>TypeDescr = atom() | string()</v>
- <v>DescrPidDesc = pid() | undefined</v>
- </type>
- <desc>
- <p>Returns a memory allocation map where the type numbers (first
- element of <c>Desc</c>) have been replaced by type descriptions,
- and pid tuples (fourth element of <c>Desc</c>) have been
- replaced by real pids.</p>
- </desc>
- </func>
- <func>
- <name>holes(MemoryData) -> ok</name>
- <fsummary>Print out the sizes of unused memory blocks</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- </type>
- <desc>
- <p>Prints out the size of each hole (i.e., the space between
- allocated blocks) on the terminal. <em>NOTE:</em> Really large holes
- are probably holes between memory segments.
- The memory allocation map has to be sorted (see
- <seealso marker="#sort/1">sort/1</seealso>).</p>
- </desc>
- </func>
- <func>
- <name>mem_limits(MemoryData) -> {Low, High}</name>
- <fsummary>Return lowest and highest memory address used</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- <v>Low = High = int()</v>
- </type>
- <desc>
- <p>Returns a tuple <c>{Low, High}</c> indicating
- the lowest and highest address used.
- The memory allocation map has to be sorted (see
- <seealso marker="#sort/1">sort/1</seealso>).</p>
- </desc>
- </func>
- <func>
- <name>memory_data() -> MemoryData | false</name>
- <fsummary>Return the current memory allocation map</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- </type>
- <desc>
- <p>Returns <c>MemoryData</c> (a the memory allocation map)
- if the emulator has been started with the "<c>+Mim true</c>"
- command-line argument; otherwise, <c>false</c>. <em>NOTE:</em><c>memory_data/0</c> blocks execution of other processes while
- the data is collected. The time it takes to collect the data can
- be substantial.</p>
- </desc>
- </func>
- <func>
- <name>memory_status(StatusType) -> [StatusInfo] | false</name>
- <fsummary>Return current memory allocation status</fsummary>
- <type>
- <v>StatusType = total | allocators | classes | types</v>
- <v>StatusInfo = {About, [Info]}</v>
- <v>About = atom()</v>
- <v>Info = {InfoName, Current, MaxSinceLast, MaxEver}</v>
- <v>InfoName = sizes|blocks</v>
- <v>Current = int()</v>
- <v>MaxSinceLast = int()</v>
- <v>MaxEver = int()</v>
- </type>
- <desc>
- <p>Returns a list of <c>StatusInfo</c> if the emulator has been
- started with the "<c>+Mis true</c>" or "<c>+Mim true</c>"
- command-line argument; otherwise, <c>false</c>. </p>
- <p>See the
- <seealso marker="#read_memory_status/1">read_memory_status/1</seealso>
- function for a description of the <c>StatusInfo</c> term.</p>
- </desc>
- </func>
- <func>
- <name>read_memory_data(File) -> MemoryData | {error, Reason}</name>
- <fsummary>Read memory allocation map</fsummary>
- <type>
- <v>File = string()</v>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- </type>
+ <name name="allocations" arity="0"/>
+ <fsummary>Return a summary of all allocations in the system.</fsummary>
<desc>
- <marker id="read_memory_data_1"></marker>
- <p>Reads a memory allocation map from the file <c>File</c> and
- returns it. The file is assumed to have been created by
- <c>store_memory_data/1</c>. The error codes are the same as for
- <c>file:consult/1</c>.</p>
+ <p>Shorthand for
+ <seealso marker="#allocations/1"><c>allocations(#{})</c>.</seealso></p>
</desc>
</func>
+
<func>
- <name>read_memory_status(File) -> MemoryStatus | {error, Reason}</name>
- <fsummary>Read memory allocation status from a file</fsummary>
- <type>
- <v>File = string()</v>
- <v>MemoryStatus = [{StatusType, [StatusInfo]}]</v>
- <v>StatusType = total | allocators | classes | types</v>
- <v>StatusInfo = {About, [Info]}</v>
- <v>About = atom()</v>
- <v>Info = {InfoName, Current, MaxSinceLast, MaxEver}</v>
- <v>InfoName = sizes|blocks</v>
- <v>Current = int()</v>
- <v>MaxSinceLast = int()</v>
- <v>MaxEver = int()</v>
- </type>
- <desc>
- <marker id="read_memory_status_1"></marker>
- <p>Reads memory allocation status from the file <c>File</c> and
- returns it. The file is assumed to have been created by
- <c>store_memory_status/1</c>. The error codes are the same as
- for <c>file:consult/1</c>.</p>
- <p>When <c>StatusType</c> is <c>allocators</c>, <c>About</c> is
- the allocator that the information is about. When
- <c>StatusType</c> is <c>types</c>, <c>About</c> is
- the memory block type that the information is about. Memory
- block types are not described other than by their name and may
- vary between emulators. When <c>StatusType</c> is <c>classes</c>,
- <c>About</c> is the memory block type class that information is
- presented about. Memory block types are classified after their
- use. Currently the following classes exist:</p>
+ <name name="allocations" arity="1"/>
+ <fsummary>Return a summary of all allocations filtered by allocator type
+ and scheduler id.</fsummary>
+ <desc>
+ <p>Returns a summary of all tagged allocations in the system,
+ optionally filtered by allocator type and scheduler id.</p>
+ <p>Only binaries and allocations made by NIFs and drivers are tagged by
+ default, but this can be configured an a per-allocator basis with the
+ <seealso marker="erts:erts_alloc#M_atags"><c>+M&lt;S&gt;atags</c>
+ </seealso> emulator option.</p>
+ <p>If tagged allocations are not enabled on any of the specified
+ allocator types, the call will fail with
+ <c>{error, not_enabled}</c>.</p>
+ <p>The following options can be used:</p>
<taglist>
- <tag><c>process_data</c></tag>
- <item>Erlang process specific data.</item>
- <tag><c>binary_data</c></tag>
- <item>Erlang binaries.</item>
- <tag><c>atom_data</c></tag>
- <item>Erlang atoms.</item>
- <tag><c>code_data</c></tag>
- <item>Erlang code.</item>
- <tag><c>system_data</c></tag>
- <item>Other data used by the system</item>
+ <tag><c>allocator_types</c></tag>
+ <item>
+ <p>The allocator types that will be searched. Defaults to all
+ <c>alloc_util</c> allocators.</p>
+ </item>
+ <tag><c>scheduler_ids</c></tag>
+ <item>
+ <p>The scheduler ids whose allocator instances will be searched. A
+ scheduler id of 0 will refer to the global instance that is not
+ tied to any particular scheduler. Defaults to all schedulers and
+ the global instance.</p>
+ </item>
+ <tag><c>histogram_start</c></tag>
+ <item>
+ <p>The upper bound of the first interval in the allocated block
+ size histograms. Defaults to 128.</p>
+ </item>
+ <tag><c>histogram_width</c></tag>
+ <item>
+ <p>The number of intervals in the allocated block size histograms.
+ Defaults to 18.</p>
+ </item>
</taglist>
- <p>When <c>InfoName</c> is <c>sizes</c>, <c>Current</c>,
- <c>MaxSinceLast</c>, and <c>MaxEver</c> are, respectively, current
- size, maximum size since last call to
- <c>store_memory_status/1</c> or <c>memory_status/1</c> with the
- specific <c>StatusType</c>, and maximum size since the emulator
- was started. When <c>InfoName</c> is <c>blocks</c>, <c>Current</c>,
- <c>MaxSinceLast</c>, and <c>MaxEver</c> are, respectively, current
- number of blocks, maximum number of blocks since last call to
- <c>store_memory_status/1</c> or <c>memory_status/1</c> with the
- specific <c>StatusType</c>, and maximum number of blocks since the
- emulator was started. </p>
- <p><em>NOTE:</em>A memory block is accounted for at
- "the first level" allocator. E.g. <c>fix_alloc</c> allocates its
- memory pools via <c>ll_alloc</c>. When a <c>fix_alloc</c> block
- is allocated, neither the block nor the pool in which it resides
- are accounted for as memory allocated via <c>ll_alloc</c> even
- though it is.</p>
- </desc>
- </func>
- <func>
- <name>sort(MemoryData) -> MemoryData</name>
- <fsummary>Sort the memory allocation list</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- </type>
- <desc>
- <marker id="sort_1"></marker>
- <p>Sorts a memory allocation map so that the addresses are in
- ascending order.</p>
- </desc>
- </func>
- <func>
- <name>store_memory_data(File) -> true|false</name>
- <fsummary>Store the current memory allocation map on a file</fsummary>
- <type>
- <v>File = string()</v>
- </type>
- <desc>
- <p>Stores the current memory allocation map on the file
- <c>File</c>. Returns <c>true</c> if the emulator has been
- started with the "<c>+Mim true</c>" command-line argument, and
- the map was successfully stored; otherwise, <c>false</c>. The
- contents of the file can later be read using
- <seealso marker="#read_memory_data/1">read_memory_data/1</seealso>.
- <em>NOTE:</em><c>store_memory_data/0</c> blocks execution of
- other processes while the data is collected. The time it takes
- to collect the data can be substantial.</p>
- </desc>
- </func>
- <func>
- <name>store_memory_status(File) -> true|false</name>
- <fsummary>Store the current memory allocation status on a file</fsummary>
- <type>
- <v>File = string()</v>
- </type>
- <desc>
- <p>Stores the current memory status on the file
- <c>File</c>. Returns <c>true</c> if the emulator has been
- started with the "<c>+Mis true</c>", or "<c>+Mim true</c>"
- command-line arguments, and the data was successfully stored;
- otherwise, <c>false</c>. The contents of the file can later be
- read using
- <seealso marker="#read_memory_status/1">read_memory_status/1</seealso>.</p>
- </desc>
- </func>
- <func>
- <name>sum_blocks(MemoryData) -> int()</name>
- <fsummary>Return the total amount of memory used</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- </type>
- <desc>
- <p>Returns the total size of the memory blocks in the list.</p>
+ <p><em>Example:</em></p>
+ <code type="none"><![CDATA[
+> instrument:allocations(#{ histogram_start => 128, histogram_width => 15 }).
+{ok,{128,0,
+ #{udp_inet =>
+ #{driver_event_state => {0,0,0,0,0,0,0,0,0,1,0,0,0,0,0}},
+ system =>
+ #{heap => {0,0,0,0,20,4,2,2,2,3,0,1,0,0,1},
+ db_term => {271,3,1,52,80,1,0,0,0,0,0,0,0,0,0},
+ code => {0,0,0,5,3,6,11,22,19,20,10,2,1,0,0},
+ binary => {18,0,0,0,7,0,0,1,0,0,0,0,0,0,0},
+ message => {0,40,78,2,2,0,0,0,0,0,0,0,0,0,0},
+ ... }
+ spawn_forker =>
+ #{driver_select_data_state =>
+ {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0}},
+ ram_file_drv => #{drv_binary => {0,0,0,0,0,0,1,0,0,0,0,0,0,0,0}},
+ prim_file =>
+ #{process_specific_data => {2,0,0,0,0,0,0,0,0,0,0,0,0,0,0},
+ nif_trap_export_entry => {0,4,0,0,0,0,0,0,0,0,0,0,0,0,0},
+ monitor_extended => {0,1,0,0,0,0,0,0,0,0,0,0,0,0,0},
+ drv_binary => {0,0,0,0,0,0,1,0,3,5,0,0,0,1,0},
+ binary => {0,4,0,0,0,0,0,0,0,0,0,0,0,0,0}},
+ prim_buffer =>
+ #{nif_internal => {0,4,0,0,0,0,0,0,0,0,0,0,0,0,0},
+ binary => {0,4,0,0,0,0,0,0,0,0,0,0,0,0,0}}}}}
+ ]]></code>
</desc>
</func>
+
<func>
- <name>type_descr(MemoryData, TypeNo) -> TypeDescr | invalid_type</name>
- <fsummary>Returns a type description</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- <v>TypeNo = int()</v>
- <v>TypeDescr = atom() | string()</v>
- </type>
+ <name name="carriers" arity="0"/>
+ <fsummary>Return a list of all carriers in the system.</fsummary>
<desc>
- <p>Returns the type description of a type number used in
- <c>MemoryData</c>.
- Valid <c>TypeNo</c>s are in the range returned by
- <seealso marker="#type_no_range/1">type_no_range/1</seealso> on
- this specific memory allocation map. If <c>TypeNo</c> is an
- invalid integer, <c>invalid_type</c> is returned.</p>
+ <p>Shorthand for
+ <seealso marker="#carriers/1"><c>carriers(#{})</c>.</seealso></p>
</desc>
</func>
+
<func>
- <name>type_no_range(MemoryData) -> {Min, Max}</name>
- <fsummary>Returns the memory block type numbers</fsummary>
- <type>
- <v>MemoryData = {term(), AllocList}</v>
- <v>AllocList = [Desc]</v>
- <v>Desc = {int(), int(), int(), PidDesc}</v>
- <v>PidDesc = {int(), int(), int()} | undefined</v>
- <v>Min = int()</v>
- <v>Max = int()</v>
- </type>
+ <name name="carriers" arity="1"/>
+ <fsummary>Return a list of all carriers filtered by allocator type and
+ scheduler id.</fsummary>
<desc>
- <marker id="type_no_range_1"></marker>
- <p>Returns the memory block type number range used in
- <c>MemoryData</c>. When the memory allocation map was generated
- by an Erlang 5.3/OTP R9C or newer emulator, all integers <c>T</c>
- that satisfy <c>Min</c> &lt;= <c>T</c> &lt;= <c>Max</c> are
- valid type numbers. When the memory allocation map was generated
- by a pre Erlang 5.3/OTP R9C emulator, all integers in the
- range are <em>not</em> valid type numbers.</p>
+ <p>Returns a summary of all carriers in the system, optionally filtered
+ by allocator type and scheduler id.</p>
+ <p>If the specified allocator types are not enabled, the call will fail
+ with <c>{error, not_enabled}</c>.</p>
+ <p>The following options can be used:</p>
+ <taglist>
+ <tag><c>allocator_types</c></tag>
+ <item>
+ <p>The allocator types that will be searched. Defaults to all
+ <c>alloc_util</c> allocators.</p>
+ </item>
+ <tag><c>scheduler_ids</c></tag>
+ <item>
+ <p>The scheduler ids whose allocator instances will be searched. A
+ scheduler id of 0 will refer to the global instance that is not
+ tied to any particular scheduler. Defaults to all schedulers and
+ the global instance.</p>
+ </item>
+ <tag><c>histogram_start</c></tag>
+ <item>
+ <p>The upper bound of the first interval in the free block size
+ histograms. Defaults to 512.</p>
+ </item>
+ <tag><c>histogram_width</c></tag>
+ <item>
+ <p>The number of intervals in the free block size histograms.
+ Defaults to 14.</p>
+ </item>
+ </taglist>
+ <p><em>Example:</em></p>
+ <code type="none"><![CDATA[
+> instrument:carriers(#{ histogram_start => 512, histogram_width => 8 }).
+{ok,{512,
+ [{ll_alloc,1048576,0,1048344,71,false,{0,0,0,0,0,0,0,0}},
+ {binary_alloc,1048576,0,324640,13,false,{3,0,0,1,0,0,0,2}},
+ {eheap_alloc,2097152,0,1037200,45,false,{2,1,1,3,4,3,2,2}},
+ {fix_alloc,32768,0,29544,82,false,{22,0,0,0,0,0,0,0}},
+ {...}|...]}}
+ ]]></code>
</desc>
</func>
+
</funcs>
<section>