On Fri, 2007-12-07 at 14:14 -0800, Jakub Narebski wrote: > > >> Is SHA a significant portion of the compute during these repacks? > > >> I should run oprofile... > > > SHA1 is almost totally insignificant on x86. It hardly shows up. But > > > we have a good optimized version there. > > > zlib tends to be a lot more noticeable (especially the > > > *uncompression*: it may be faster than compression, but it's done _so_ > > > much more that it totally dominates). > > > > Have you considered alternatives, like: > > http://www.oberhumer.com/opensource/ucl/ > > <quote> > As compared to LZO, the UCL algorithms achieve a better compression > ratio but *decompression* is a little bit slower. See below for some > rough timings. > </quote> > > It is uncompression speed that is more important, because it is used > much more often.
I know, but the point is not what is the fastestest, but if it's fast enough to get off the profiles. I think UCL is fast enough since it's still times faster than zlib. Anyway, LZO is GPL too, so why not considering it too. They are good libraries. -- Giovanni Bajo
