Messages in this thread | | | Date | Wed, 9 Apr 2014 09:57:06 -0400 | From | Don Zickus <> | Subject | Re: [PATCH 6/6] perf, sort: Allow unique sorting instead of combining hist_entries |
| |
On Wed, Apr 09, 2014 at 02:31:00PM +0900, Namhyung Kim wrote: > On Mon, 24 Mar 2014 15:34:36 -0400, Don Zickus wrote: > > The cache contention tools needs to keep all the perf records unique in order > > to properly parse all the data. Currently add_hist_entry() will combine > > the duplicate record and add the weight/period to the existing record. > > > > This throws away the unique data the cache contention tool needs (mainly > > the data source). Create a flag to force the records to stay unique. > > No. This is why I said you need to add 'mem' and 'snoop' sort keys into > the c2c tool. This is not how sort works IMHO - if you need to make > samples unique let the sort key(s) distinguish them somehow, or you can > combine same samples (in terms of sort kes) and use the combined entry's > stat.nr_events and stat.period or weight.
Ok. I understand your point. Perhaps this was my lack of fully understanding the sorting algorithm when I did this. I can look into adding the 'mem' and 'snoop'.
One concern I do have is we were caculating statistics based on the weight (mean, median, stddev). I was afraid that combining the entries would throw off our calculations as we could no longer accurately determine them any more. Is that true?
Cheers, Don
| |