RFC: /proc/<pid>/sched should contain cumulative data for all threadsin process

From: Chris Friesen
Date: Mon Feb 07 2011 - 17:31:03 EST



Hi,

We've got a tool that gathers lots of scheduling data for each process
(not task/thread) on the system.

For /proc/<pid>/{stat,io} this is straightforward, as the per-thread
values are summed together for the process as a whole.

However, /proc/<pid>/sched only shows the data for the individual thread
with the same tid as the pid. To get a per-process view we need to
manually scan all the threads and sum them--and this can get expensive
due to all the extra file operations, parsing, etc.

Was this a concious design decision, or just an oversight? Would a
patch converting it to whole-process values be accepted or is it enough
of a standard interface that we can't break existing apps that expect
the current behaviour?

Thanks,
Chris

--
Chris Friesen
Software Developer
GENBAND
chris.friesen@xxxxxxxxxxx
www.genband.com
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