On Thu, 16 Aug 2012 17:06:47 +0200 Johannes Stezenbach wrote: > Well, ~2x speedup on x86 is certainly a good achievement, but there > are more ARM based devices than there are PCs, and I guess many > embedded devices use lzo compressed kernels and file systems > while I'm not convinced many PCs rely on lzo in the kernel. Keep in mind that a major user of LZO is the BTRFS filesystem, and I believe it is used much more often on larger machines than on ARM, in fact it had problems operating on ARM at all, until quite recently. > I know everyone's either busy or on vacation, but it would > be so cool if someone could test on a more modern ARM core, > with the userspace test code I posted it should be easy to do. I have locked the Allwinner A10 CPU in my Mele A2000 to 60 MHz using cpufreq-set, and ran your test. rnd.lzo is a 9 MB file from /dev/urandom compressed with lzo. There doesn't seem to be a significant difference between all three variants. # time for i in {1..20}; do old/unlzop < rnd.lzo >/dev/null ; done real 0m11.353s user 0m3.060s sys 0m8.170s # time for i in {1..20}; do new/unlzop < rnd.lzo >/dev/null ; done real 0m11.416s user 0m3.030s sys 0m8.200s # time for i in {1..20}; do test/unlzop < rnd.lzo >/dev/null ; done real 0m11.310s user 0m3.100s sys 0m8.150s -- With respect, Roman ~~~~~~~~~~~~~~~~~~~~~~~~~~~ "Stallman had a printer, with code he could not see. So he began to tinker, and set the software free."