Re: [PATCH] perf record: Allow poll timeout to be specified

[David Ahern]

On 3/25/15 6:14 AM, Arnaldo Carvalho de Melo wrote:
> If David doesn't come up with something I'll probably will, as making
> 'trace' use the ordered_samples, like 'perf top' does (initially with
> some arbitrary reasonable poll timeout value), is a low hanging fruit to
> get those multi-CPU tracepoints sorted until I get something better in
> place...

I have thought about it. It needs to be an adaptive algorithm:
1. start at 100 msec.
2. Read the maps. How much data are there (not events, but data size)? 
3. Adjust poll timeout up or down with some heuristic -- maybe something 
similar to the algorithm perf-top uses for removing entries from the 
histograms.

That said, I still thinking giving the user control is not a crazy idea.

David
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/