On Mon, 11 Dec 2023 22:41:56 GMT, Yi-Fan Tsai <d...@openjdk.org> wrote:
>> `jcmd Compiler.perfmap` uses the hard-coded file name for a perf map: >> `/tmp/perf-%d.map`. This change adds an optional argument for specifying a >> file name. >> >> `jcmd PID help Compiler.perfmap` shows the following usage. >> >> >> Compiler.perfmap >> Write map file for Linux perf tool. >> >> Impact: Low >> >> Syntax : Compiler.perfmap [<filename>] >> >> Arguments: >> filename : [optional] Name of the map file (STRING, no default value) >> >> >> The following section of man page is also updated. (`man -l >> src/jdk.jcmd/share/man/jcmd.1`) >> >> >> Compiler.perfmap [arguments] (Linux only) >> Write map file for Linux perf tool. >> >> Impact: Low >> >> arguments: >> >> ยท filename: (Optional) Name of the map file (STRING, no >> default value) >> >> If filename is not specified, a default file name is chosen >> using the pid of the target JVM process. For example, if the pid is 12345, >> then >> the default filename will be /tmp/perf-12345.map. > > Yi-Fan Tsai has updated the pull request incrementally with one additional > commit since the last revision: > > Update copyright of PerfMapTest The man page says "no default value" but then right below describes the default value, which is confusing. I would remove "no default value". The code already deals with patterns, so why not allow a pattern like /dir/perf-%x.map and document that the platform-specific process id will be passed to String.format() to expand any formatting tokens in the string? ------------- PR Comment: https://git.openjdk.org/jdk/pull/15871#issuecomment-1854683037
