Messages in this thread | | | Date | Wed, 10 Sep 2008 07:34:27 -0700 | From | Balbir Singh <> | Subject | Re: [Approach #2] [RFC][PATCH] Remove cgroup member from struct page |
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KAMEZAWA Hiroyuki wrote: > On Thu, 11 Sep 2008 07:02:44 +1000 > Nick Piggin <nickpiggin@yahoo.com.au> wrote: > >> On Wednesday 10 September 2008 21:03, KAMEZAWA Hiroyuki wrote: >>> On Thu, 11 Sep 2008 06:44:37 +1000 >>> >>> Nick Piggin <nickpiggin@yahoo.com.au> wrote: >>>> On Wednesday 10 September 2008 11:49, KAMEZAWA Hiroyuki wrote: >>>>> On Tue, 9 Sep 2008 18:20:48 -0700 >>>>> >>>>> Balbir Singh <balbir@linux.vnet.ibm.com> wrote: >>>>>> * KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> [2008-09-09 >>>>>> 21:30:12]: OK, here is approach #2, it works for me and gives me >>>>>> really good performance (surpassing even the current memory >>>>>> controller). I am seeing almost a 7% increase >>>>> This number is from pre-allcation, maybe. >>>>> We really do alloc-at-boot all page_cgroup ? This seems a big change. >>>> It seems really nice to me -- we get the best of both worlds, less >>>> overhead for those who don't enable the memory controller, and even >>>> better performance for those who do. >>> No trobles for me for allocating-all-at-boot policy. >>> My small concern is >>> - wasting page_cgroup for hugepage area. >>> - memory hotplug >> In those cases you still waste the struct page area too. I realise that >> isn't a good way to justify even more wastage. But I guess it is >> relatively low. At least, I would think the users would be more happy to >> get a 7% performance increase for small pages! :) >> > I guess the increase mostly because we can completely avoid kmalloc/kfree slow path. >
Correct
> Balbir, how about fix our way to allocate-all-at-boot-policy ? > If you say yes, I think I can help you and I'll find usable part from my garbage. >
I am perfectly fine with it, I'll need your expertise to get the alloc-at-boot-policy correct.
> Following is lockless+remove-page-cgroup-pointer-from-page-struct patch's result. > > rc5-mm1 > == > Execl Throughput 3006.5 lps (29.8 secs, 3 samples) > C Compiler Throughput 1006.7 lpm (60.0 secs, 3 samples) > Shell Scripts (1 concurrent) 4863.7 lpm (60.0 secs, 3 samples) > Shell Scripts (8 concurrent) 943.7 lpm (60.0 secs, 3 samples) > Shell Scripts (16 concurrent) 482.7 lpm (60.0 secs, 3 samples) > Dc: sqrt(2) to 99 decimal places 124804.9 lpm (30.0 secs, 3 samples) > > lockless > == > Execl Throughput 3035.5 lps (29.6 secs, 3 samples) > C Compiler Throughput 1010.3 lpm (60.0 secs, 3 samples) > Shell Scripts (1 concurrent) 4881.0 lpm (60.0 secs, 3 samples) > Shell Scripts (8 concurrent) 947.7 lpm (60.0 secs, 3 samples) > Shell Scripts (16 concurrent) 485.0 lpm (60.0 secs, 3 samples) > Dc: sqrt(2) to 99 decimal places 125437.9 lpm (30.0 secs, 3 samples) > > lockless + remove page cgroup pointer (my version). > == > Execl Throughput 3021.1 lps (29.5 secs, 3 samples) > C Compiler Throughput 980.3 lpm (60.0 secs, 3 samples) > Shell Scripts (1 concurrent) 4600.0 lpm (60.0 secs, 3 samples) > Shell Scripts (8 concurrent) 915.7 lpm (60.0 secs, 3 samples) > Shell Scripts (16 concurrent) 468.3 lpm (60.0 secs, 3 samples) > Dc: sqrt(2) to 99 decimal places 124909.1 lpm (30.0 secs, 3 samples) > > Oh,yes. siginificant slow down. I'm glad to kick this patch out to trash box. > > Thanks, > -Kame >
-- Thanks, Balbir
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