Autogenerated HTML docs for v2.22.0-rc0
diff --git a/technical/api-index.html b/technical/api-index.html index 12489d7..ff5ef09 100644 --- a/technical/api-index.html +++ b/technical/api-index.html
@@ -880,7 +880,7 @@ <div id="footer"> <div id="footer-text"> Last updated - 2019-03-07 12:16:34 JST + 2019-05-14 01:01:19 JST </div> </div> </body>
diff --git a/technical/api-trace2.html b/technical/api-trace2.html index dbfe551..6b32b7c 100644 --- a/technical/api-trace2.html +++ b/technical/api-trace2.html
@@ -756,6 +756,10 @@ <div class="paragraph"><p>Targets are defined using a VTable allowing easy extension to other formats in the future. This might be used to define a binary format, for example.</p></div> +<div class="paragraph"><p>Trace2 is controlled using <code>trace2.*</code> config values in the system and +global config files and <code>GIT_TR2*</code> environment variables. Trace2 does +not read from repo local or worktree config files or respect <code>-c</code> +command line config settings.</p></div> </div> </div> <div class="sect1"> @@ -763,20 +767,27 @@ <div class="sectionbody"> <div class="paragraph"><p>Trace2 defines the following set of Trace2 Targets. Format details are given in a later section.</p></div> -<div class="dlist"><dl> -<dt class="hdlist1"> -<code>GIT_TR2</code> (NORMAL) -</dt> -<dd> -<p> - a simple printf format like GIT_TRACE. -</p> +<div class="sect2"> +<h3 id="_the_normal_format_target">The Normal Format Target</h3> +<div class="paragraph"><p>The normal format target is a tradition printf format and similar +to GIT_TRACE format. This format is enabled with the <code>GIT_TR</code> +environment variable or the <code>trace2.normalTarget</code> system or global +config setting.</p></div> +<div class="paragraph"><p>For example</p></div> <div class="listingblock"> <div class="content"> <pre><code>$ export GIT_TR2=~/log.normal $ git version git version 2.20.1.155.g426c96fcdb</code></pre> </div></div> +<div class="paragraph"><p>or</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git config --global trace2.normalTarget ~/log.normal +$ git version +git version 2.20.1.155.g426c96fcdb</code></pre> +</div></div> +<div class="paragraph"><p>yields</p></div> <div class="listingblock"> <div class="content"> <pre><code>$ cat ~/log.normal @@ -786,121 +797,112 @@ 12:28:42.621215 git.c:662 exit elapsed:0.001227 code:0 12:28:42.621250 trace2/tr2_tgt_normal.c:124 atexit elapsed:0.001265 code:0</code></pre> </div></div> -</dd> -<dt class="hdlist1"> -<code>GIT_TR2_PERF</code> (PERF) -</dt> -<dd> -<p> - a column-based format to replace GIT_TRACE_PERFORMANCE suitable for - development and testing, possibly to complement tools like gprof. -</p> +</div> +<div class="sect2"> +<h3 id="_the_performance_format_target">The Performance Format Target</h3> +<div class="paragraph"><p>The performance format target (PERF) is a column-based format to +replace GIT_TRACE_PERFORMANCE and is suitable for development and +testing, possibly to complement tools like gprof. This format is +enabled with the <code>GIT_TR2_PERF</code> environment variable or the +<code>trace2.perfTarget</code> system or global config setting.</p></div> +<div class="paragraph"><p>For example</p></div> <div class="listingblock"> <div class="content"> <pre><code>$ export GIT_TR2_PERF=~/log.perf $ git version git version 2.20.1.155.g426c96fcdb</code></pre> </div></div> +<div class="paragraph"><p>or</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git config --global trace2.perfTarget ~/log.perf +$ git version +git version 2.20.1.155.g426c96fcdb</code></pre> +</div></div> +<div class="paragraph"><p>yields</p></div> <div class="listingblock"> <div class="content"> <pre><code>$ cat ~/log.perf 12:28:42.620675 common-main.c:38 | d0 | main | version | | | | | 2.20.1.155.g426c96fcdb -12:28:42.621001 common-main.c:39 | d0 | main | start | | | | | git version +12:28:42.621001 common-main.c:39 | d0 | main | start | | 0.001173 | | | git version 12:28:42.621111 git.c:432 | d0 | main | cmd_name | | | | | version (version) 12:28:42.621225 git.c:662 | d0 | main | exit | | 0.001227 | | | code:0 12:28:42.621259 trace2/tr2_tgt_perf.c:211 | d0 | main | atexit | | 0.001265 | | | code:0</code></pre> </div></div> -</dd> -<dt class="hdlist1"> -<code>GIT_TR2_EVENT</code> (EVENT) -</dt> -<dd> -<p> - a JSON-based format of event data suitable for telemetry analysis. -</p> +</div> +<div class="sect2"> +<h3 id="_the_event_format_target">The Event Format Target</h3> +<div class="paragraph"><p>The event format target is a JSON-based format of event data suitable +for telemetry analysis. This format is enabled with the <code>GIT_TR2_EVENT</code> +environment variable or the <code>trace2.eventTarget</code> system or global config +setting.</p></div> +<div class="paragraph"><p>For example</p></div> <div class="listingblock"> <div class="content"> <pre><code>$ export GIT_TR2_EVENT=~/log.event $ git version git version 2.20.1.155.g426c96fcdb</code></pre> </div></div> +<div class="paragraph"><p>or</p></div> +<div class="listingblock"> +<div class="content"> +<pre><code>$ git config --global trace2.eventTarget ~/log.event +$ git version +git version 2.20.1.155.g426c96fcdb</code></pre> +</div></div> +<div class="paragraph"><p>yields</p></div> <div class="listingblock"> <div class="content"> <pre><code>$ cat ~/log.event -{"event":"version","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.620713","file":"common-main.c","line":38,"evt":"1","exe":"2.20.1.155.g426c96fcdb"} -{"event":"start","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621027","file":"common-main.c","line":39,"argv":["git","version"]} -{"event":"cmd_name","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621122","file":"git.c","line":432,"name":"version","hierarchy":"version"} -{"event":"exit","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621236","file":"git.c","line":662,"t_abs":0.001227,"code":0} -{"event":"atexit","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621268","file":"trace2/tr2_tgt_event.c","line":163,"t_abs":0.001265,"code":0}</code></pre> +{"event":"version","sid":"sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.620713Z","file":"common-main.c","line":38,"evt":"1","exe":"2.20.1.155.g426c96fcdb"} +{"event":"start","sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.621027Z","file":"common-main.c","line":39,"t_abs":0.001173,"argv":["git","version"]} +{"event":"cmd_name","sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.621122Z","file":"git.c","line":432,"name":"version","hierarchy":"version"} +{"event":"exit","sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.621236Z","file":"git.c","line":662,"t_abs":0.001227,"code":0} +{"event":"atexit","sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.621268Z","file":"trace2/tr2_tgt_event.c","line":163,"t_abs":0.001265,"code":0}</code></pre> </div></div> -</dd> -</dl></div> </div> -</div> -<div class="sect1"> -<h2 id="_enabling_a_target">Enabling a Target</h2> -<div class="sectionbody"> -<div class="paragraph"><p>A Trace2 Target is enabled when the corresponding environment variable -(<code>GIT_TR2</code>, <code>GIT_TR2_PERF</code>, or <code>GIT_TR2_EVENT</code>) is set. The following -values are recognized.</p></div> -<div class="dlist"><dl> -<dt class="hdlist1"> -<code>0</code> -</dt> -<dt class="hdlist1"> -<code>false</code> -</dt> -<dd> -<p> - Disables the target. -</p> -</dd> -<dt class="hdlist1"> -<code>1</code> -</dt> -<dt class="hdlist1"> -<code>true</code> -</dt> -<dd> -<p> - Enables the target and writes stream to <code>STDERR</code>. -</p> -</dd> -<dt class="hdlist1"> -<code>[2-9]</code> -</dt> -<dd> -<p> - Enables the target and writes to the already opened file descriptor. -</p> -</dd> -<dt class="hdlist1"> -<code><absolute-pathname></code> -</dt> -<dd> -<p> - Enables the target, opens and writes to the file in append mode. -</p> -<div class="literalblock"> +<div class="sect2"> +<h3 id="_enabling_a_target">Enabling a Target</h3> +<div class="paragraph"><p>To enable a target, set the corresponding environment variable or +system or global config value to one of the following:</p></div> +<div class="openblock"> <div class="content"> -<pre><code>If the target already exists and is a directory, the traces will be +<div class="ulist"><ul> +<li> +<p> +<code>0</code> or <code>false</code> - Disables the target. +</p> +</li> +<li> +<p> +<code>1</code> or <code>true</code> - Writes to <code>STDERR</code>. +</p> +</li> +<li> +<p> +<code>[2-9]</code> - Writes to the already opened file descriptor. +</p> +</li> +<li> +<p> +<code><absolute-pathname></code> - Writes to the file in append mode. +</p> +</li> +<li> +<p> +<code>af_unix:[<socket_type>:]<absolute-pathname></code> - Write to a +Unix DomainSocket (on platforms that support them). Socket +type can be either <code>stream</code> or <code>dgram</code>; if omitted Git will +try both. +</p> +</li> +</ul></div> +</div></div> +<div class="paragraph"><p>If the target already exists and is a directory, the traces will be written to files (one per process) underneath the given directory. They will be named according to the last component of the SID (optionally -followed by a counter to avoid filename collisions).</code></pre> -</div></div> -</dd> -<dt class="hdlist1"> -<code>af_unix:[<socket_type>:]<absolute-pathname></code> -</dt> -<dd> -<p> - Enables the target, opens and writes to a Unix Domain Socket - (on platforms that support them). -</p> -<div class="paragraph"><p>Socket type can be either <code>stream</code> or <code>dgram</code>. If the socket type is -omitted, Git will try both.</p></div> -</dd> -</dl></div> +followed by a counter to avoid filename collisions).</p></div> +</div> </div> </div> <div class="sect1"> @@ -944,18 +946,28 @@ <div class="paragraph"><p>These are concerned with the lifetime of the overall git process.</p></div> <div class="dlist"><dl> <dt class="hdlist1"> +<code>void trace2_initialize_clock()</code> +</dt> +<dd> +<p> + Initialize the Trace2 start clock and nothing else. This should + be called at the very top of main() to capture the process start + time and reduce startup order dependencies. +</p> +</dd> +<dt class="hdlist1"> <code>void trace2_initialize()</code> </dt> <dd> <p> Determines if any Trace2 Targets should be enabled and - initializes the Trace2 facility. This includes starting the - elapsed time clocks and thread local storage (TLS). + initializes the Trace2 facility. This includes setting up the + Trace2 thread local storage (TLS). </p> <div class="paragraph"><p>This function emits a "version" message containing the version of git and the Trace2 protocol.</p></div> <div class="paragraph"><p>This function should be called from <code>main()</code> as early as possible in -the life of the process.</p></div> +the life of the process after essential process initialization.</p></div> </dd> <dt class="hdlist1"> <code>int trace2_is_enabled()</code> @@ -1060,7 +1072,8 @@ Emits a "def_param" messages for "important" configuration settings. </p> -<div class="paragraph"><p>The environment variable <code>GIT_TR2_CONFIG_PARAMS</code> can be set to a +<div class="paragraph"><p>The environment variable <code>GIT_TR2_CONFIG_PARAMS</code> or the <code>trace2.configParams</code> +config value can be set to a list of patterns of important configuration settings, for example: <code>core.*,remote.*.url</code>. This function will iterate over all config settings and emit a "def_param" message for each match.</p></div> @@ -1070,8 +1083,8 @@ </dt> <dd> <p> - Emits a "def_param" message for a specific configuration - setting IFF it matches the <code>GIT_TR2_CONFIG_PARAMS</code> pattern. + Emits a "def_param" message for a new or updated key/value + pair IF <code>key</code> is considered important. </p> <div class="paragraph"><p>This is used to hook into <code>git_config_set()</code> and catch any configuration changes and update a value previously reported by @@ -1277,8 +1290,6 @@ <div class="sectionbody"> <div class="sect2"> <h3 id="_normal_format">NORMAL Format</h3> -<div class="paragraph"><p>NORMAL format is enabled when the <code>GIT_TR2</code> environment variable is -set.</p></div> <div class="paragraph"><p>Events are written as lines of the form:</p></div> <div class="listingblock"> <div class="content"> @@ -1304,16 +1315,14 @@ not escaped, so the event may spill across multiple lines.</p></div> </dd> </dl></div> -<div class="paragraph"><p>If <code>GIT_TR2_BRIEF</code> is true, the <code>time</code>, <code>filename</code>, and <code>line</code> fields -are omitted.</p></div> +<div class="paragraph"><p>If <code>GIT_TR2_BRIEF</code> or <code>trace2.normalBrief</code> is true, the <code>time</code>, <code>filename</code>, +and <code>line</code> fields are omitted.</p></div> <div class="paragraph"><p>This target is intended to be more of a summary (like GIT_TRACE) and less detailed than the other targets. It ignores thread, region, and data messages, for example.</p></div> </div> <div class="sect2"> <h3 id="_perf_format">PERF Format</h3> -<div class="paragraph"><p>PERF format is enabled when the <code>GIT_TR2_PERF</code> environment variable -is set.</p></div> <div class="paragraph"><p>Events are written as lines of the form:</p></div> <div class="listingblock"> <div class="content"> @@ -1413,8 +1422,8 @@ <pre><code>15:33:33.532712 wt-status.c:2310 | d0 | main | region_enter | r1 | 0.126064 | | status | label:print 15:33:33.532712 wt-status.c:2331 | d0 | main | region_leave | r1 | 0.127568 | 0.001504 | status | label:print</code></pre> </div></div> -<div class="paragraph"><p>If <code>GIT_TR2_PERF_BRIEF</code> is true, the <code>time</code>, <code>file</code>, and <code>line</code> -fields are omitted.</p></div> +<div class="paragraph"><p>If <code>GIT_TR2_PERF_BRIEF</code> or <code>trace2.perfBrief</code> is true, the <code>time</code>, <code>file</code>, +and <code>line</code> fields are omitted.</p></div> <div class="listingblock"> <div class="content"> <pre><code>d0 | main | region_leave | r1 | 0.011717 | 0.009122 | index | label:preload</code></pre> @@ -1424,8 +1433,6 @@ </div> <div class="sect2"> <h3 id="_event_format">EVENT Format</h3> -<div class="paragraph"><p>EVENT format is enabled when the <code>GIT_TR2_EVENT</code> environment -variable is set.</p></div> <div class="paragraph"><p>Each event is a JSON-object containing multiple key/value pairs written as a single line and followed by a LF.</p></div> <div class="listingblock"> @@ -1441,11 +1448,11 @@ <div class="content"> <pre><code>{ "event":"version", - "sid":"1547659722619736-11614", + "sid":"20190408T191827.272759Z-H9b68c35f-P00003510", "thread":"main", - "time":"2019-01-16 17:28:42.620713", + "time":"2019-04-08T19:18:27.282761Z", "file":"common-main.c", - "line":38, + "line":42, ... }</code></pre> </div></div> @@ -1513,9 +1520,9 @@ </p> </dd> </dl></div> -<div class="paragraph"><p>If <code>GIT_TR2_EVENT_BRIEF</code> is true, the <code>file</code> and <code>line</code> fields are omitted -from all events and the <code>time</code> field is only present on the "start" and -"atexit" events.</p></div> +<div class="paragraph"><p>If <code>GIT_TR2_EVENT_BRIEF</code> or <code>trace2.eventBrief</code> is true, the <code>file</code> +and <code>line</code> fields are omitted from all events and the <code>time</code> field is +only present on the "start" and "atexit" events.</p></div> </div> <div class="sect3"> <h4 id="_event_specific_key_value_pairs">Event-Specific Key/Value Pairs</h4> @@ -1549,6 +1556,7 @@ <pre><code>{ "event":"start", ... + "t_abs":0.001227, # elapsed time in seconds "argv":["git","version"] }</code></pre> </div></div> @@ -1909,7 +1917,7 @@ </div></div> <div class="paragraph"><p>The <code>category</code> field may be used in a future enhancement to do category-based filtering.</p></div> -<div class="paragraph"><p>The <code>GIT_TR2_EVENT_NESTING</code> environment variable can be used to +<div class="paragraph"><p><code>GIT_TR2_EVENT_NESTING</code> or <code>trace2.eventNesting</code> can be used to filter deeply nested regions and data events. It defaults to "2".</p></div> </dd> <dt class="hdlist1"> @@ -2172,7 +2180,7 @@ $ cat ~/log.perf d0 | main | version | | | | | 2.20.1.160.g5676107ecd.dirty -d0 | main | start | | | | | git status +d0 | main | start | | 0.001173 | | | git status d0 | main | def_repo | r1 | | | | worktree:/Users/jeffhost/work/gfw d0 | main | cmd_name | | | | | status (status) ... @@ -2215,7 +2223,7 @@ ... $ cat ~/log.perf d0 | main | version | | | | | 2.20.1.162.gb4ccea44db.dirty -d0 | main | start | | | | | git status +d0 | main | start | | 0.001173 | | | git status d0 | main | def_repo | r1 | | | | worktree:/Users/jeffhost/work/gfw d0 | main | cmd_name | | | | | status (status) ... @@ -2273,7 +2281,7 @@ ... $ cat ~/log.perf d0 | main | version | | | | | 2.20.1.156.gf9916ae094.dirty -d0 | main | start | | | | | git status +d0 | main | start | | 0.001173 | | | git status d0 | main | def_repo | r1 | | | | worktree:/Users/jeffhost/work/gfw d0 | main | cmd_name | | | | | status (status) d0 | main | region_enter | r1 | 0.001791 | | index | label:do_read_index .git/index @@ -2434,7 +2442,7 @@ <div id="footer"> <div id="footer-text"> Last updated - 2019-05-09 02:15:17 JST + 2019-05-14 01:01:04 JST </div> </div> </body> diff --git a/technical/api-trace2.txt b/technical/api-trace2.txt index d0948ba..9e585b8 100644 --- a/technical/api-trace2.txt +++ b/technical/api-trace2.txt
@@ -22,21 +22,41 @@ formats in the future. This might be used to define a binary format, for example. +Trace2 is controlled using `trace2.*` config values in the system and +global config files and `GIT_TR2*` environment variables. Trace2 does +not read from repo local or worktree config files or respect `-c` +command line config settings. + == Trace2 Targets Trace2 defines the following set of Trace2 Targets. Format details are given in a later section. -`GIT_TR2` (NORMAL):: +=== The Normal Format Target - a simple printf format like GIT_TRACE. -+ +The normal format target is a tradition printf format and similar +to GIT_TRACE format. This format is enabled with the `GIT_TR` +environment variable or the `trace2.normalTarget` system or global +config setting. + +For example + ------------ $ export GIT_TR2=~/log.normal $ git version git version 2.20.1.155.g426c96fcdb ------------ -+ + +or + +------------ +$ git config --global trace2.normalTarget ~/log.normal +$ git version +git version 2.20.1.155.g426c96fcdb +------------ + +yields + ------------ $ cat ~/log.normal 12:28:42.620009 common-main.c:38 version 2.20.1.155.g426c96fcdb @@ -46,81 +66,86 @@ 12:28:42.621250 trace2/tr2_tgt_normal.c:124 atexit elapsed:0.001265 code:0 ------------ -`GIT_TR2_PERF` (PERF):: +=== The Performance Format Target - a column-based format to replace GIT_TRACE_PERFORMANCE suitable for - development and testing, possibly to complement tools like gprof. -+ +The performance format target (PERF) is a column-based format to +replace GIT_TRACE_PERFORMANCE and is suitable for development and +testing, possibly to complement tools like gprof. This format is +enabled with the `GIT_TR2_PERF` environment variable or the +`trace2.perfTarget` system or global config setting. + +For example + ------------ $ export GIT_TR2_PERF=~/log.perf $ git version git version 2.20.1.155.g426c96fcdb ------------ -+ + +or + +------------ +$ git config --global trace2.perfTarget ~/log.perf +$ git version +git version 2.20.1.155.g426c96fcdb +------------ + +yields + ------------ $ cat ~/log.perf 12:28:42.620675 common-main.c:38 | d0 | main | version | | | | | 2.20.1.155.g426c96fcdb -12:28:42.621001 common-main.c:39 | d0 | main | start | | | | | git version +12:28:42.621001 common-main.c:39 | d0 | main | start | | 0.001173 | | | git version 12:28:42.621111 git.c:432 | d0 | main | cmd_name | | | | | version (version) 12:28:42.621225 git.c:662 | d0 | main | exit | | 0.001227 | | | code:0 12:28:42.621259 trace2/tr2_tgt_perf.c:211 | d0 | main | atexit | | 0.001265 | | | code:0 ------------ -`GIT_TR2_EVENT` (EVENT):: +=== The Event Format Target - a JSON-based format of event data suitable for telemetry analysis. -+ +The event format target is a JSON-based format of event data suitable +for telemetry analysis. This format is enabled with the `GIT_TR2_EVENT` +environment variable or the `trace2.eventTarget` system or global config +setting. + +For example + ------------ $ export GIT_TR2_EVENT=~/log.event $ git version git version 2.20.1.155.g426c96fcdb ------------ -+ + +or + +------------ +$ git config --global trace2.eventTarget ~/log.event +$ git version +git version 2.20.1.155.g426c96fcdb +------------ + +yields + ------------ $ cat ~/log.event -{"event":"version","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.620713","file":"common-main.c","line":38,"evt":"1","exe":"2.20.1.155.g426c96fcdb"} -{"event":"start","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621027","file":"common-main.c","line":39,"argv":["git","version"]} -{"event":"cmd_name","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621122","file":"git.c","line":432,"name":"version","hierarchy":"version"} -{"event":"exit","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621236","file":"git.c","line":662,"t_abs":0.001227,"code":0} -{"event":"atexit","sid":"1547659722619736-11614","thread":"main","time":"2019-01-16 17:28:42.621268","file":"trace2/tr2_tgt_event.c","line":163,"t_abs":0.001265,"code":0} +{"event":"version","sid":"sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.620713Z","file":"common-main.c","line":38,"evt":"1","exe":"2.20.1.155.g426c96fcdb"} +{"event":"start","sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.621027Z","file":"common-main.c","line":39,"t_abs":0.001173,"argv":["git","version"]} +{"event":"cmd_name","sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.621122Z","file":"git.c","line":432,"name":"version","hierarchy":"version"} +{"event":"exit","sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.621236Z","file":"git.c","line":662,"t_abs":0.001227,"code":0} +{"event":"atexit","sid":"20190408T191610.507018Z-H9b68c35f-P000059a8","thread":"main","time":"2019-01-16T17:28:42.621268Z","file":"trace2/tr2_tgt_event.c","line":163,"t_abs":0.001265,"code":0} ------------ -== Enabling a Target +=== Enabling a Target -A Trace2 Target is enabled when the corresponding environment variable -(`GIT_TR2`, `GIT_TR2_PERF`, or `GIT_TR2_EVENT`) is set. The following -values are recognized. +To enable a target, set the corresponding environment variable or +system or global config value to one of the following: -`0`:: -`false`:: +include::../trace2-target-values.txt[] - Disables the target. - -`1`:: -`true`:: - - Enables the target and writes stream to `STDERR`. - -`[2-9]`:: - - Enables the target and writes to the already opened file descriptor. - -`<absolute-pathname>`:: - - Enables the target, opens and writes to the file in append mode. - - If the target already exists and is a directory, the traces will be - written to files (one per process) underneath the given directory. They - will be named according to the last component of the SID (optionally - followed by a counter to avoid filename collisions). - -`af_unix:[<socket_type>:]<absolute-pathname>`:: - - Enables the target, opens and writes to a Unix Domain Socket - (on platforms that support them). -+ -Socket type can be either `stream` or `dgram`. If the socket type is -omitted, Git will try both. +If the target already exists and is a directory, the traces will be +written to files (one per process) underneath the given directory. They +will be named according to the last component of the SID (optionally +followed by a counter to avoid filename collisions). == Trace2 API @@ -165,17 +190,23 @@ These are concerned with the lifetime of the overall git process. +`void trace2_initialize_clock()`:: + + Initialize the Trace2 start clock and nothing else. This should + be called at the very top of main() to capture the process start + time and reduce startup order dependencies. + `void trace2_initialize()`:: Determines if any Trace2 Targets should be enabled and - initializes the Trace2 facility. This includes starting the - elapsed time clocks and thread local storage (TLS). + initializes the Trace2 facility. This includes setting up the + Trace2 thread local storage (TLS). + This function emits a "version" message containing the version of git and the Trace2 protocol. + This function should be called from `main()` as early as possible in -the life of the process. +the life of the process after essential process initialization. `int trace2_is_enabled()`:: @@ -242,15 +273,16 @@ Emits a "def_param" messages for "important" configuration settings. + -The environment variable `GIT_TR2_CONFIG_PARAMS` can be set to a +The environment variable `GIT_TR2_CONFIG_PARAMS` or the `trace2.configParams` +config value can be set to a list of patterns of important configuration settings, for example: `core.*,remote.*.url`. This function will iterate over all config settings and emit a "def_param" message for each match. `void trace2_cmd_set_config(const char *key, const char *value)`:: - Emits a "def_param" message for a specific configuration - setting IFF it matches the `GIT_TR2_CONFIG_PARAMS` pattern. + Emits a "def_param" message for a new or updated key/value + pair IF `key` is considered important. + This is used to hook into `git_config_set()` and catch any configuration changes and update a value previously reported by @@ -417,9 +449,6 @@ === NORMAL Format -NORMAL format is enabled when the `GIT_TR2` environment variable is -set. - Events are written as lines of the form: ------------ @@ -436,8 +465,8 @@ Note that this may contain embedded LF or CRLF characters that are not escaped, so the event may spill across multiple lines. -If `GIT_TR2_BRIEF` is true, the `time`, `filename`, and `line` fields -are omitted. +If `GIT_TR2_BRIEF` or `trace2.normalBrief` is true, the `time`, `filename`, +and `line` fields are omitted. This target is intended to be more of a summary (like GIT_TRACE) and less detailed than the other targets. It ignores thread, region, and @@ -445,9 +474,6 @@ === PERF Format -PERF format is enabled when the `GIT_TR2_PERF` environment variable -is set. - Events are written as lines of the form: ------------ @@ -507,8 +533,8 @@ 15:33:33.532712 wt-status.c:2331 | d0 | main | region_leave | r1 | 0.127568 | 0.001504 | status | label:print ------------ -If `GIT_TR2_PERF_BRIEF` is true, the `time`, `file`, and `line` -fields are omitted. +If `GIT_TR2_PERF_BRIEF` or `trace2.perfBrief` is true, the `time`, `file`, +and `line` fields are omitted. ------------ d0 | main | region_leave | r1 | 0.011717 | 0.009122 | index | label:preload @@ -519,9 +545,6 @@ === EVENT Format -EVENT format is enabled when the `GIT_TR2_EVENT` environment -variable is set. - Each event is a JSON-object containing multiple key/value pairs written as a single line and followed by a LF. @@ -539,11 +562,11 @@ ------------ { "event":"version", - "sid":"1547659722619736-11614", + "sid":"20190408T191827.272759Z-H9b68c35f-P00003510", "thread":"main", - "time":"2019-01-16 17:28:42.620713", + "time":"2019-04-08T19:18:27.282761Z", "file":"common-main.c", - "line":38, + "line":42, ... } ------------ @@ -575,9 +598,9 @@ `"repo":<repo-id>`:: when present, is the integer repo-id as described previously. -If `GIT_TR2_EVENT_BRIEF` is true, the `file` and `line` fields are omitted -from all events and the `time` field is only present on the "start" and -"atexit" events. +If `GIT_TR2_EVENT_BRIEF` or `trace2.eventBrief` is true, the `file` +and `line` fields are omitted from all events and the `time` field is +only present on the "start" and "atexit" events. ==== Event-Specific Key/Value Pairs @@ -600,6 +623,7 @@ { "event":"start", ... + "t_abs":0.001227, # elapsed time in seconds "argv":["git","version"] } ------------ @@ -887,7 +911,7 @@ The `category` field may be used in a future enhancement to do category-based filtering. + -The `GIT_TR2_EVENT_NESTING` environment variable can be used to +`GIT_TR2_EVENT_NESTING` or `trace2.eventNesting` can be used to filter deeply nested regions and data events. It defaults to "2". `"region_leave"`:: @@ -1117,7 +1141,7 @@ $ cat ~/log.perf d0 | main | version | | | | | 2.20.1.160.g5676107ecd.dirty -d0 | main | start | | | | | git status +d0 | main | start | | 0.001173 | | | git status d0 | main | def_repo | r1 | | | | worktree:/Users/jeffhost/work/gfw d0 | main | cmd_name | | | | | status (status) ... @@ -1162,7 +1186,7 @@ ... $ cat ~/log.perf d0 | main | version | | | | | 2.20.1.162.gb4ccea44db.dirty -d0 | main | start | | | | | git status +d0 | main | start | | 0.001173 | | | git status d0 | main | def_repo | r1 | | | | worktree:/Users/jeffhost/work/gfw d0 | main | cmd_name | | | | | status (status) ... @@ -1218,7 +1242,7 @@ ... $ cat ~/log.perf d0 | main | version | | | | | 2.20.1.156.gf9916ae094.dirty -d0 | main | start | | | | | git status +d0 | main | start | | 0.001173 | | | git status d0 | main | def_repo | r1 | | | | worktree:/Users/jeffhost/work/gfw d0 | main | cmd_name | | | | | status (status) d0 | main | region_enter | r1 | 0.001791 | | index | label:do_read_index .git/index 