On Fri, Dec 10, 2021 at 4:23 AM Jiri Olsa [off-list ref] wrote:

On Thu, Dec 09, 2021 at 03:39:20PM -0800, Namhyung Kim wrote:

quoted

Hi Jiri,

On Thu, Dec 9, 2021 at 12:04 PM Jiri Olsa [off-list ref] wrote:

quoted

hi,
after migrating to fedora 35 I found perf record hanging on exit
and it's because fedora 35 sets DEBUGINFOD_URLS that triggers
debuginfod query which might take long time to process.

I discussed this briefly with Frank and I'm sending the change
to disable debuginfod by default in perf record.

Frank had other idea we could discuss here to fork or just spawn
"/usr/bin/debuginfod-find ...." into background after perf record.

Perhaps there are other ways as well, hence this is RFC ;-)

I thought the debuginfod was for perf report, not record.
Maybe I'm missing something but how about moving it to
report?  We can talk to debuginfod after checking the local
build-id cache and binary on the system.

at the end of the perf record we populate buildid cache
with profiled binaries for the current perf.data

**IF** there's DEBUGINFOD_URLS defined, that code will
also ask debuginfod for binaries it could not find on
the system

Yeah, I know what you're doing.  But I guess debuginfod
contains binaries for the distro and they'd be available for
a while.  Then I think we don't need to do it at perf record.

Thanks,
Namhyung