[flac-dev] Performance checks

Miroslav Lichvar mlichvar at redhat.com
Mon Jun 3 04:24:09 PDT 2013

On Sat, Jun 01, 2013 at 02:33:55PM +0300, Janne Hyvärinen wrote:
> On 1.6.2013 14:24, Janne Hyvärinen wrote:
> > I can confirm. I see 10% speed improvement with that change on Core i7.
> > Decoding a 1h18min38.133s long test FLAC -8 encoded file takes with
> > normal asm optimizations 7.656s (speed: 616,266x realtime) and with that
> > tiny change 6.937s (speed: 680,140x realtime).

Thanks for the testing.

> I noticed a side effect for this change. Encoding got a bit slower at 
> least when md5 checksumming is enabled.

That's odd. How much slower was the encoding? Could it be caused by
increase in the size of the function (only with -funroll-loops?) and
not fitting in the cache during encoding?

It might be good to use -funroll-loops only with some files, IIRC it
helped most to stream_encoder.c.

Miroslav Lichvar

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