On Sun, Feb 25, 2018 at 03:35:39PM +0100, Kevin Kofler wrote: > Tomasz Kłoczko wrote: > > BTW size. Did you try to compile systemd with optimisation for size (-Os)? > > > > There are many Linux packages which should be optimised for size > > because they provide binaries which are speed critical like boot > > loaders and boot tools (grub, lilo, gubby) some diagnostics and system > > tools (dmidecode, strace, parted, shadow-utils, util-linux, lvm, mdadm > > ..) > > In many cases optimisations for size provides faster code at it has > > lower probability generate CPU cache misses. > > If -Os code is actually faster than -O2, then we should change the > distrowide default. Dunno. Speed is complicated, since even though it's fairly easy to do some microbenchmarking using unittests, it's hard to measure something representative. But size is easy: $ du -s /var/tmp/inst-O* 74428 /var/tmp/inst-O3 56136 /var/tmp/inst-O3-lto 61992 /var/tmp/inst-Os 43572 /var/tmp/inst-Os-lto (Those are installation sizes from DESTDIR=/var/tmp/inst... ninja -C build install, unstripped, in kB.) Zbyszek _______________________________________________ devel mailing list -- devel@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to devel-leave@xxxxxxxxxxxxxxxxxxxxxxx
