On 3.6.2013 14:24, Miroslav Lichvar wrote: > 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. >
I neglected to mention that the testing was done with MSVC 2012 and on Windows. I did some futher testing after your mail and noticed that with GCC the encoding speed is unaffected. Decoding speed increase is not as big as with MSVC, only 7% improvement with it. With MSVC the drop in encoding speed with my test file is 0.4%. Other perhaps interesting speed results: MSVC compile with unaltered sources is 1.9% faster than GCC at encoding. GCC decoding is 8% faster than MSVC before the modification and 5.6% after the modification. These results are without changing any compiling options on either compiler. _______________________________________________ flac-dev mailing list [email protected] http://lists.xiph.org/mailman/listinfo/flac-dev
