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