Correction: on non-x86 architectures fPIC doesn't have any significant performance *dis*advantages.
And on x86 (not on amd64 however) gettimeofday is a syscall, which causes context switching and is generally bad to call rapidly. On Thu, Jan 1, 2009 at 8:09 PM, Nephyrin Zey <nephy...@doublezen.net> wrote: > Linux srcds has used a ton of CPU forever. The main frame loop is > optimized for a windows 66hz timer environment. Hence, linux servers > are 'perma-boosted' and chug inordinate amounts of CPU for minor FPS > increases, and they give us no variables to tweak the various sleep > times/calculations that impact this. SSE2 is still broken in linux > srcds. it also uses gettimeofday heavily, which was bad enough that > the l4d team specifically redid that part of the engine. The engine > uses 2-3% of the CPU entirely idle on kernels with a high response > rate (HPET/1000hz/other common things), which caused the l4d team to > put in a hibernation mode. > > The x86 binaries still use -fPIC > On other arches (amd64) it don't have any performance advantage due to > the necessary calls being there, but on x86 PIC clobbers a register > and causes call heavy binaries like srcds to use upwards of 6% of > their CPU time on thunks. Nvidia's linux OpenGL library, mpeg > decoders, etc, all use non-fPIC shared objects on x86. > > And yeah, SourceTV murders my server in CPU usage. I also noticed FPS > dips to the point where I had to fuck with the sleep timer to make > things go smoothly. I made a few threads about this but valve isn't > really all that interested. > > - Neph > > On Tue, Dec 30, 2008 at 2:10 AM, bob dolet <bgcl...@gmail.com> wrote: >> Whenever sourcetv is enabled on a tf2 srcds instance extreme server side fps >> dips occur. This happens regardless of fps settings in the server.cfg and >> with as little as 0 players on the server. Running the 2.6.26.6 kernel with >> RT patch on debian lenny and setting the srcds process to realtime priority >> fps remain extremely stable without sourcetv enabled. This issue seems to >> have a noticeable impact on gameplay. >> _______________________________________________ >> To unsubscribe, edit your list preferences, or view the list archives, >> please visit: >> http://list.valvesoftware.com/mailman/listinfo/hlds_linux >> > _______________________________________________ To unsubscribe, edit your list preferences, or view the list archives, please visit: http://list.valvesoftware.com/mailman/listinfo/hlds_linux
