* Arnaldo Carvalho de Melo <[email protected]> wrote:
> Em Tue, Mar 24, 2015 at 05:12:11PM +0100, Ingo Molnar escreveu:
> > * David Ahern <[email protected]> wrote:
> >
> > > Record currently wakes up based on watermarks to read events
> > > from the mmaps and write them out to the file. The result is a
> > > file that can have large blocks of events per mmap before a
> > > finished round event is added to the stream. This in turn
> > > affects the quantity of events that have to be passed through
> > > the ordered events queue before results can be displayed to the
> > > user. For commands like perf-script this can lead to long
> > > unnecessarily long delays before a user gets output. Large
> > > systems (e.g, 1024 cpus) further compound this effect. I have
> > > seen instances where I have to wait 45 minutes for perf-script
> > > to process a 5GB file before any events are shown.
> > >
> > > This patch adds an option to perf-record to allow a user to
> > > specify the poll timeout in msec. For example using 100 msec
> > > timeouts similar to perf-top means the mmaps are traversed much
> > > more frequently leading to a smoother analysis side.
> >
> > Please tune the default value (perhaps influenced by N_PROC?) so
> > that users will get sane behavior without having to specify this
> > option!
>
> Isn't this a followup patch? [...]
Will a followup patch be written?
Thanks,
Ingo
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