Re: BDR, wal sender, high system cpu, mutex_lock_common

On 2017-10-12 10:25:43 +0800, Craig Ringer wrote:
> On 4 October 2017 at 00:21, milist ujang <ujang(dot)milist(at)gmail(dot)com> wrote:
> > On Tue, Oct 3, 2017 at 8:49 PM, Craig Ringer <craig(at)2ndquadrant(dot)com> wrote:
> >>
> >>
> >> Can you get stacks please?
> >>
> >> Use -g
> >
> >
> > # Events: 2K cpu-clock
> > #
> > # Overhead Command Shared Object Symbol
> > # ........ ........ ................. ............................
> > #
> > 86.96% postgres [kernel.kallsyms] [k] __mutex_lock_common.isra.5
> > |
> > --- __mutex_lock_common.isra.5
> > read
>
>
> Unfortunately it looks like you're using a postgres built with
> -fomit-frame-pointers (the default) on x64, with an older perf not
> built with libunwind. This produces useless stacks.

Just read this mail, but for libunwind to work you'd have to specify
"--call-graph dwarf", no?

- Andres