Messages in this thread | | | Date | Wed, 10 Nov 2021 13:49:21 -0400 | From | Jason Gunthorpe <> | Subject | Re: [PATCH v3 00/15] Free user PTE page table pages |
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On Wed, Nov 10, 2021 at 06:37:46PM +0100, David Hildenbrand wrote:
> It will be if we somewhat frequent when reclaim an empty PTE page table > as soon as it turns empty.
What do you think is the frequency of unlocked page table walks that this would have to block on?
> Also, it adds complexity for something that is only a problem in some > corner cases -- sparse memory mappings, especially relevant for some > memory allocators after freeing a lot of memory or running VMs with > memory ballooning after inflating the balloon. Some of these use cases > might be good with just triggering page table reclaim manually from user > space.
Right, this is why it would be nice if the complexity could address more than one problem, like the existing complex locking around the thp stuff..
Jason
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