Messages in this thread | | | Date | Wed, 03 Jul 2013 14:47:58 -0400 | From | Yannick Brosseau <> | Subject | Re: [-stable 3.8.1 performance regression] madvise POSIX_FADV_DONTNEED |
| |
On 2013-07-03 04:47, Mel Gorman wrote: >> Given it is just a hint, we should be allowed to perform page >> > deactivation lazily. Is there any fundamental reason to wait for worker >> > threads on each CPU to complete their lru drain before returning from >> > fadvise() to user-space ? >> > > Only to make sure they pages are actually dropped as requested. The reason > the wait was introduced in the first place was that page cache was filling > up even with the fadvise calls and causing disruption. In 3.11 disruption > due to this sort of parallel IO should be reduced but making fadvise work > properly is reasonable in itself. Was that patch I posted ever tested or > did I manage to miss it? I did test it. On our test case, we get a worst result with it.
Yannick
| |