linux-kernel - Re: [PATCH] perf report: show sort

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 14 Mar 2017 10:16:44 +0800
From:   "Du, Changbin" <changbin.du@...el.com>
To:     Arnaldo Carvalho de Melo <acme@...nel.org>
Cc:     changbin.du@...el.com, peterz@...radead.org, mingo@...hat.com,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] perf report: show sort_order in title

On Mon, Mar 13, 2017 at 11:57:18AM -0300, Arnaldo Carvalho de Melo wrote:
> > I'll just rename this to use the tools/perf/ style for such functions,
> > making it:
> > 
> > 	static int hists__scnprintf_sort_fields(hists, buf, size)
> 
> But then, while testing, 
> 
> Before:
> 
>   $ perf report
>   Samples: 405  of event 'cycles', Event count (approx.): 101733003
>   Overhead  Command          Shared Object                        Symbol
>     11.15%  swapper          [kernel.vmlinux]                     [k] intel_idle
>      3.00%  firefox          libxul.so                            [.] 0x0000000001298b8d
>      1.74%  swapper          [kernel.vmlinux]                     [k] update_blocked_averages
>      1.69%  qemu-system-x86  [kernel.vmlinux]                     [k] __fget
>      1.18%  swapper          [kernel.vmlinux]                     [k] update_wall_time
> 
>   Tip: Save output of perf stat using: perf stat record <target workload>
> 
> After:
> 
>   $ perf report
>   Samples: 405  of event 'cycles', Event count (approx.): 101733003, Sort by: Children,Overhead,Command,Shared Object,Symbol
>   Overhead  Command          Shared Object                        Symbol
>     11.15%  swapper          [kernel.vmlinux]                     [k] intel_idle
>      3.00%  firefox          libxul.so                            [.] 0x0000000001298b8d
>      1.74%  swapper          [kernel.vmlinux]                     [k] update_blocked_averages
>      1.69%  qemu-system-x86  [kernel.vmlinux]                     [k] __fget
>      1.18%  swapper          [kernel.vmlinux]                     [k] update_wall_time
> 
> 
> I see now duplication of info, where is the value? Can you show the usecase in
> a compelling way?
> 
> - Arnaldo

Thanks for trying. The key idea is to show how does the data sort, especially
the first sort key. When I use some GUI based perf tool, I can see how
my data is sorted by checking the report header status. I think this is
a good for browser.

You are right, the info is duplicated. I got another idea that we show a '↓' at
the header string and only for the first sort key. What do you think?

$ perf report
   Samples: 405  of event 'cycles', Event count (approx.): 101733003
   ↓Overhead  Command          Shared Object                        Symbol
     11.15%  swapper          [kernel.vmlinux]                     [k] intel_idle
      3.00%  firefox          libxul.so                            [.] 0x0000000001298b8d
      1.74%  swapper          [kernel.vmlinux]                     [k] update_blocked_averages

Another idea I want to add is to support dynamic sorting. For me, I use perf to
analysing entire system performance, and the data is very large. Then sometimes
it take as long as ~10 minitues to read perf data. So I think if we can change
sort w/o reload data will be good.

-- 
Thanks,
Changbin Du

Download attachment "signature.asc" of type "application/pgp-signature" (474 bytes)