Ingo Molnar wrote: > * Al Boldi <[EMAIL PROTECTED]> wrote: > > > ok. I think i might finally have found the bug causing this. Could > > > you try the fix below, does your webserver thread-startup test work > > > any better? > > > > It seems to help somewhat, but the problem is still visible. Even > > v20.3 on 2.6.22.5 didn't help. > > > > It does look related to ia-boosting, so I turned off __update_curr > > like Roman mentioned, which had an enormous smoothing effect, but then > > nice levels completely break down and lockup the system. > > you can turn sleeper-fairness off via: > > echo 28 > /proc/sys/kernel/sched_features > > another thing to try would be: > > echo 12 > /proc/sys/kernel/sched_features > > (that's the new-task penalty turned off.) > > Another thing to try would be to edit this: > > if (sysctl_sched_features & SCHED_FEAT_START_DEBIT) > p->se.wait_runtime = -(sched_granularity(cfs_rq) / 2); > > to: > > if (sysctl_sched_features & SCHED_FEAT_START_DEBIT) > p->se.wait_runtime = -(sched_granularity(cfs_rq); > > and could you also check 20.4 on 2.6.22.5 perhaps, or very latest -git? > (Peter has experienced smaller spikes with that.)
Ok, I tried all your suggestions, but nothing works as smooth as removing __update_curr. Does the problem show on your machine with the 3x gears under X-vesa test? Thanks! -- Al - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
