From: Teng Long <dyroneteng@xxxxxxxxx>
It's supported to print "interesting" config key-value paire
to tr2 log by setting "GIT_TRACE2_CONFIG_PARAMS" environment
variable and the "trace2.configparam" config, let's add the
related docs in Documentaion/technical/api-trace2.txt.
Signed-off-by: Teng Long <dyroneteng@xxxxxxxxx>
---
Documentation/technical/api-trace2.txt | 32 ++++++++++++++++++++++++++
1 file changed, 32 insertions(+)
diff --git a/Documentation/technical/api-trace2.txt b/Documentation/technical/api-trace2.txt
index 77a150b30e..ddc0bfb9c9 100644
--- a/Documentation/technical/api-trace2.txt
+++ b/Documentation/technical/api-trace2.txt
@@ -717,6 +717,7 @@ The "exec_id" field is a command-unique id and is only useful if the
{
"event":"def_param",
...
+ "scope":"global",
"param":"core.abbrev",
"value":"7"
}
@@ -1207,6 +1208,37 @@ at offset 508.
This example also shows that thread names are assigned in a racy manner
as each thread starts and allocates TLS storage.
+Print Configs::
+
+ Dump "interesting" config values to trace2 log.
++
+The environment variable `GIT_TRACE2_CONFIG_PARAMS` and configuration
+`trace2.configparams` can be used to output config values which you care
+about(see linkgit:git-config[1). For example:
++
+----------------
+$ git config color.ui auto
+----------------
++
+Then, mark the config `color.ui` as "interesting" config with
+`GIT_TRACE2_CONFIG_PARAMS`:
++
+----------------
+$ export GIT_TRACE2_PERF_BRIEF=1
+$ export GIT_TRACE2_PERF=~/log.perf
+$ export GIT_TRACE2_CONFIG_PARAMS=color.ui
+$ git version
+...
+$ cat ~/log.perf
+d0 | main | version | | | | | ...
+d0 | main | start | | 0.001642 | | | /usr/local/bin/git version
+d0 | main | cmd_name | | | | | version (version)
+d0 | main | def_param | | | | | color.ui:auto
+d0 | main | data | r0 | 0.002100 | 0.002100 | fsync | fsync/writeout-only:0
+d0 | main | data | r0 | 0.002126 | 0.002126 | fsync | fsync/hardware-flush:0
+d0 | main | exit | | 0.002142 | | | code:0
+d0 | main | atexit | | 0.002161 | | | code:0
+----------------
== Future Work
=== Relationship to the Existing Trace Api (api-trace.txt)
--
2.37.1.1.g8cbb44ffc4.dirty
