On Sat, Jan 27, 2007 at 12:41:54AM -0800, Junio C Hamano wrote: > > Based on some (limited) profiling with Shark it seems we spend about > > 50% of our CPU time doing zlib decompression of objects and almost > > another 14% parsing the tree objects to apply the path limiter. > > I once tried to use zlib compression level 0 for tree objects > and did not see much difference -- maybe I should dig it up and > find out why. I don't know exactly what Shawn meant, but a considerable amount of time in a blame is spent decompressing the blobs. Just for fun, some numbers: Fully packed, warm cache, core.compression = -1: $ time git blame Makefile >/dev/null real 0m5.537s user 0m5.500s sys 0m0.032s Fully packed, warm cache, core.compression = 0: $ time git blame Makefile >/dev/null real 0m3.001s user 0m2.984s sys 0m0.012s That's 45% savings. The resulting pack sizes are 11932K compressed and 22308 uncompressed. -Peff - To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html