I know that RELENG_7 is not considered very near-release, but I thought I'd give my 2? in the hope that I might have a little influence on the scheduler development to my benefit. The switch from RELENG_6 to RELENG_7 went relatively smooth and apart from ipw causing panics. However there is one thing that's disturbing and this is the scheduler. I only have single core machines, so whatever I say only applies to those. If you think single-core machines are no longer important, feel free to ignore this. In deed, just ignore me however much you like.>From my perspective scheduling on RELENG_6 was way better. Even on a fullworkload like a portupgrade the focused application (both in X and on the console) always received enough cycles to run smoothly and applications that ran in background like audio players also kept on running fine. Quite the contrary on RELENG_7. During a portupgrade or even worse 'pkgdb -L' (recovering lost dependencies) audio players (both graphical and mplayer) scatter, either because they don't get the hard-disk or CPU-cycles (which one, I don't know) and the focused application also often hangs. It just looks like occasionally (under load) everything freezes for a second and then goes on relatively normal. I've got the impression that things compile a little faster (that might be my imagination, though), but I'd rather have a smooth working experience. This is just my view of the situation and I suppose it is only one of many. I bid you be merciful with us single-core people, who cannot afford a slick multi-core machine, because we worry how to pay for our food at the end of the month.
[LoN]Kamikaze wrote:> I know that RELENG_7 is not considered very near-release, but I thought I'd > give my 2? in the hope that I might have a little influence on the scheduler > development to my benefit. > > The switch from RELENG_6 to RELENG_7 went relatively smooth and apart from ipw > causing panics. However there is one thing that's disturbing and this is the > scheduler. I only have single core machines, so whatever I say only applies to > those. If you think single-core machines are no longer important, feel free to > ignore this. In deed, just ignore me however much you like. > >>From my perspective scheduling on RELENG_6 was way better. Even on a full > workload like a portupgrade the focused application (both in X and on the > console) always received enough cycles to run smoothly and applications that > ran in background like audio players also kept on running fine. > > Quite the contrary on RELENG_7. During a portupgrade or even worse 'pkgdb -L' > (recovering lost dependencies) audio players (both graphical and mplayer) > scatter, either because they don't get the hard-disk or CPU-cycles (which one, > I don't know) and the focused application also often hangs. It just looks like > occasionally (under load) everything freezes for a second and then goes on > relatively normal. > > I've got the impression that things compile a little faster (that might be my > imagination, though), but I'd rather have a smooth working experience. > > This is just my view of the situation and I suppose it is only one of many. I > bid you be merciful with us single-core people, who cannot afford a slick > multi-core machine, because we worry how to pay for our food at the end of the > month.Not to say that any problems that might have developed with SCHED_4BSD should not be fixed, but you should give SCHED_ULE a try since it brings benefits even for single CPU systems (e.g. better interactive response). Kris
Bengt Ahlgren wrote:> "[LoN]Kamikaze" <LoN_Kamikaze@gmx.de> writes: > >> From my perspective scheduling on RELENG_6 was way better. Even on a full >> workload like a portupgrade the focused application (both in X and on the >> console) always received enough cycles to run smoothly and applications that >> ran in background like audio players also kept on running fine. >> >> Quite the contrary on RELENG_7. During a portupgrade or even worse 'pkgdb -L' >> (recovering lost dependencies) audio players (both graphical and mplayer) >> scatter, either because they don't get the hard-disk or CPU-cycles (which one, >> I don't know) and the focused application also often hangs. It just looks like >> occasionally (under load) everything freezes for a second and then goes on >> relatively normal. > > Do you have ATA write-caching on or off? My experience is that if you > turn caching off (on RELENG_6_x at least, have not tried 7) the > machine often freezes for seconds when you are writing a lot to the > disk. > > Bengt >Write-caching is on on my machines.
"[LoN]Kamikaze" <LoN_Kamikaze@gmx.de> writes:>>>From my perspective scheduling on RELENG_6 was way better. Even on a full > workload like a portupgrade the focused application (both in X and on the > console) always received enough cycles to run smoothly and applications that > ran in background like audio players also kept on running fine. > > Quite the contrary on RELENG_7. During a portupgrade or even worse 'pkgdb -L' > (recovering lost dependencies) audio players (both graphical and mplayer) > scatter, either because they don't get the hard-disk or CPU-cycles (which one, > I don't know) and the focused application also often hangs. It just looks like > occasionally (under load) everything freezes for a second and then goes on > relatively normal.Do you have ATA write-caching on or off? My experience is that if you turn caching off (on RELENG_6_x at least, have not tried 7) the machine often freezes for seconds when you are writing a lot to the disk. Bengt