Re: [PATCH RFC V4 5/6] perf top: switch to backward overwrite mode

2017-10-03 Thread Jiri Olsa
On Mon, Oct 02, 2017 at 05:19:41PM +, Liang, Kan wrote: > > > > On Fri, Sep 29, 2017 at 07:47:56AM -0700, kan.li...@intel.com wrote: > > > From: Kan Liang > > > > > > perf_top__mmap_read has severe performance issue in Knights > > > Landing/Mill, when monitoring in heavy load system. It cost

Re: [PATCH RFC V4 5/6] perf top: switch to backward overwrite mode

2017-10-02 Thread a...@kernel.org
Em Mon, Oct 02, 2017 at 05:19:41PM +, Liang, Kan escreveu: > > > > On Fri, Sep 29, 2017 at 07:47:56AM -0700, kan.li...@intel.com wrote: > > > From: Kan Liang > > > > > > perf_top__mmap_read has severe performance issue in Knights > > > Landing/Mill, when monitoring in heavy load system. It c

RE: [PATCH RFC V4 5/6] perf top: switch to backward overwrite mode

2017-10-02 Thread Liang, Kan
> On Fri, Sep 29, 2017 at 07:47:56AM -0700, kan.li...@intel.com wrote: > > From: Kan Liang > > > > perf_top__mmap_read has severe performance issue in Knights > > Landing/Mill, when monitoring in heavy load system. It costs several > > minutes to finish, which is unacceptable. > > > > perf top w

Re: [PATCH RFC V4 5/6] perf top: switch to backward overwrite mode

2017-09-30 Thread Jiri Olsa
On Fri, Sep 29, 2017 at 07:47:56AM -0700, kan.li...@intel.com wrote: > From: Kan Liang > > perf_top__mmap_read has severe performance issue in > Knights Landing/Mill, when monitoring in heavy load system. It costs > several minutes to finish, which is unacceptable. > > perf top was overwrite mod

[PATCH RFC V4 5/6] perf top: switch to backward overwrite mode

2017-09-29 Thread kan . liang
From: Kan Liang perf_top__mmap_read has severe performance issue in Knights Landing/Mill, when monitoring in heavy load system. It costs several minutes to finish, which is unacceptable. perf top was overwrite mode. But it is changed to non overwrite mode since commit 93fc64f14472 ("perf top: Sw