On Tue, Sep 30, 2014 at 10:32 PM, Mike Shal <[email protected]> wrote:
> > On Wed, Sep 24, 2014 at 3:03 AM, Freddie Chopin <[email protected]> > wrote: > >> On 09/24/2014 02:40 AM, Mike Shal wrote: >> >>> Build time increased by over 100% compared to what? >>> >> >> Full rebuild WITH ^c^ takes 69s / 63s (first / second run). The same full >> rebuild without this flag takes half that time - 31s / 29s. >> > > Ahh, ok. I think this is attributed to a combination of tup inefficiently > setting up the chroot environment each time, plus the extra overhead of all > file read/writes (including things like the shell/compiler/etc) going > through FUSE. These are all definitely things that should be improved, > though again the read/write FUSE issue is problematic getting it fixed > upstream. > > I forgot to mention - one thing you can do to help alleviate the FUSE overhead on Linux is to set the CPU governor to "performance". By default (at least on Ubuntu), the CPU governor is set to "ondemand", which plays poorly with FUSE. As far as I can tell, the ondemand setting never really detects that it should scale up the cpu when running a task inside a FUSE fs. It seems that neither the FUSE thread, nor the task running inside it is able to consume enough cpu to warrant bumping it up, so they both stay slow. I use these bash functions: function setgov () { echo "$1" | sudo tee /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor } function getgov() { cat /sys/devices/system/cpu/cpu*/cpufreq/scaling_governor } So "setgov performance" and see if that helps at all. -Mike -- -- tup-users mailing list email: [email protected] unsubscribe: [email protected] options: http://groups.google.com/group/tup-users?hl=en --- You received this message because you are subscribed to the Google Groups "tup-users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
