On Friday 02 September 2016 07:29 PM, Peter Zijlstra wrote:
On Fri, Sep 02, 2016 at 07:25:31PM +0530, Hari Bathini wrote:
I'm thinking this value is mostly the same for tasks, just like COMM and
I think so, too. Namespaces aren't changed that often for tasks...
MMAP. Could we therefore not emit (sideband) events whenever a task
changes namespace and get the same information but with tons less data?
You mean, something like PERF_RECORD_NAMESPACE that
emits events on fork, clone, setns..?
Yep.
Ok. Thanks!
That also gives the possibility of recording all namespaces, not just
the one.
True. If we record all namespaces, container identifier interpretation
can be left to the userspace to decide, which is much more flexible...
The only complication is initial state, on record start you'd have to
trawl /proc and generate 'fake' namespace records for all (relevant)
tasks.
We do the same with MMAP records, we parse /proc/$pid/maps for that.
Is this namespace stuff available in /proc somewhere?
Yes, Peter. /proc/$pid/ns
Will work on this and respin...
Thanks
Hari
