Re: [PATCH 6/7] perf kvm: move perf_kvm__mmap_read into session utils

[David Ahern]

On 6/20/14, 8:44 AM, Arnaldo Carvalho de Melo wrote:
> Em Fri, Jun 20, 2014 at 02:49:48PM +0400, Stanislav Fomichev escreveu:
> > It will be reused by perf trace in the following commit.
>
> I know this is needed, but one of the goals when I started builtin-trace
> was not to use perf_session at all, as it initially was just about the
> live mode.
>
> record/replay came later and ended up needing it,

perf-kvm does not use the session code because I kept tripping over the 
out of order timestamp problem. By limiting the number of events read in 
a single pass I was able to smooth out the load and avoided hitting it 
as often. As I mentioned before the final piece was using the perf_clock 
timestamp at the start of the round to ensure I never hit it.

Stanislav: are you seeing out of order timestamp errors or just trying 
to reuse the live code from perf-kvm?

David
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