From linux-kernel Sat Aug 21 09:37:29 2004 From: Lee Revell Date: Sat, 21 Aug 2004 09:37:29 +0000 To: linux-kernel Subject: Re: [patch] voluntary-preempt-2.6.8.1-P5 Message-Id: <1093081049.854.101.camel () krustophenia ! net> X-MARC-Message: https://marc.info/?l=linux-kernel&m=109308116611884 On Sat, 2004-08-21 at 05:31, Ingo Molnar wrote: > * Lee Revell wrote: > > > Sorry, I was thinking of this one: > > > > http://krustophenia.net/testresults.php?dataset=2.6.8.1-P6#/var/www/2.6.8.1-P6/trace10.txt > > ok, reduced the zap block size to 8 pages a time. It should not be a big > issue to have this at a low value because we dont retry anything and we > do a full TLB flush only once. (subsequent flushes are caught by the > tlb->need_flush optimization.) > This one is interesting. What is going on here? preemption latency trace v1.0.1 ------------------------------- latency: 146 us, entries: 45 (45) ----------------- | task: pdflush/33, uid:0 nice:0 policy:0 rt_prio:0 ----------------- => started at: find_get_pages_tag+0x19/0x90 => ended at: find_get_pages_tag+0x61/0x90 =======> 00000001 0.000ms (+0.000ms): find_get_pages_tag (pagevec_lookup_tag) 00000001 0.000ms (+0.000ms): radix_tree_gang_lookup_tag (find_get_pages_tag) 00000001 0.001ms (+0.000ms): __lookup_tag (radix_tree_gang_lookup_tag) 00000001 0.007ms (+0.005ms): __lookup_tag (radix_tree_gang_lookup_tag) [ 20-30 more of these ] 00000001 0.119ms (+0.003ms): __lookup_tag (radix_tree_gang_lookup_tag) 00000001 0.125ms (+0.005ms): __lookup_tag (radix_tree_gang_lookup_tag) 00010001 0.132ms (+0.007ms): do_IRQ (find_get_pages_tag) 00010002 0.133ms (+0.000ms): mask_and_ack_8259A (do_IRQ) 00010002 0.137ms (+0.004ms): generic_redirect_hardirq (do_IRQ) 00010002 0.138ms (+0.000ms): wake_up_process (generic_redirect_hardirq) 00010002 0.138ms (+0.000ms): try_to_wake_up (wake_up_process) 00010002 0.138ms (+0.000ms): task_rq_lock (try_to_wake_up) 00010003 0.139ms (+0.000ms): activate_task (try_to_wake_up) 00010003 0.139ms (+0.000ms): sched_clock (activate_task) 00010003 0.140ms (+0.000ms): recalc_task_prio (activate_task) 00010003 0.141ms (+0.000ms): effective_prio (recalc_task_prio) 00010003 0.141ms (+0.000ms): enqueue_task (activate_task) 00010002 0.141ms (+0.000ms): preempt_schedule (try_to_wake_up) 00010001 0.142ms (+0.000ms): preempt_schedule (do_IRQ) 00000001 0.143ms (+0.001ms): sub_preempt_count (find_get_pages_tag) Lee - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/