Re: [PATCHSET 00/17] perf report: Add -F option for specifying output fields (v4)

[Namhyung Kim <namhyung@kernel.org>]

Hi Don,

2014-04-23 (수), 08:58 -0400, Don Zickus:
> On Wed, Apr 23, 2014 at 03:15:35PM +0900, Namhyung Kim wrote:
> > On Tue, 22 Apr 2014 17:16:47 -0400, Don Zickus wrote:
> > > ./perf mem record -a grep -r foo /* > /dev/null
> > > ./perf mem report -F overhead,symbol_daddr,pid -s symbol_daddr,pid --stdio 
> > >
> > > I was thinking I could sort everything based on the symbol_daddr and pid.
> > > Then re-sort the output to display the highest 'symbol_daddr,pid' pair.
> > > But it didn't seem to work that way.  Instead it seems like I get the
> > > original sort just displayed in the -F format.
> > 
> > Could you please show me the output of your example?
> 
> 
> # To display the perf.data header info, please use --header/--header-only
> # options.
> #
> # Samples: 96K of event 'cpu/mem-loads/pp'
> # Total weight : 1102938
> # Sort order   : symbol_daddr,pid
> #
> # Overhead Data Symbol          Command:  Pid
> # ........ ......................................................................
> #
>      0.00%  [k] 0xffff8807a8c1cf80 grep:116437
>      0.00%  [k] 0xffff8807a8c8cee0 grep:116437
>      0.00%  [k] 0xffff8807a8dceea0 grep:116437
>      0.01%  [k] 0xffff8807a9298dc0 grep:116437
>      0.01%  [k] 0xffff8807a934be40 grep:116437
>      0.00%  [k] 0xffff8807a9416ec0 grep:116437
>      0.02%  [k] 0xffff8807a9735700 grep:116437
>      0.00%  [k] 0xffff8807a98e9460 grep:116437
>      0.02%  [k] 0xffff8807a9afc890 grep:116437
>      0.00%  [k] 0xffff8807aa64feb0 grep:116437
>      0.02%  [k] 0xffff8807aa6b0030 grep:116437

Hmm.. it seems that it's exactly sorted by the data symbol addresses, so
I don't see any problem here.  What did you expect?  If you want to see
those symbol_daddr,pid pair to be sorted by overhead, you can use the
one of -F or -s option only.

IOW, "perf mem report -F overhead,symbol_daddr,pid" and "perf mem report
-s symbol_daddr,pid" should show same result.  FYI but "perf mem report
-F overhead,symbol_daddr,pid -s symbol_addr,pid" will be different.

It's due to a compatibility reason.  If -s option is used without -F
option, it'll prepend 'overhead' sort key to preserve old behavior (adds
the fields to output but sort by overhead only).

Thanks,
Namhyung