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From:   "Wang, Wei W" <wei.w.wang@intel.com>
To:     David Hildenbrand <david@redhat.com>,
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Subject: RE: [PATCH RFC] virtio_balloon: conservative balloon page shrinking
Thread-Topic: [PATCH RFC] virtio_balloon: conservative balloon page shrinking
Thread-Index: AQHV3Mq/N+pHUOUW3kyXc/hsfZBMQqgNWrYAgACKBvD//3w6AIAAhvTQ
Date:   Thu, 6 Feb 2020 09:44:17 +0000
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On Thursday, February 6, 2020 5:32 PM, David Hildenbrand wrote:
> 
> If the page cache is empty, a drop_slab() will deflate the whole balloon if I
> am not wrong.
> 
> Especially, a echo 3 > /proc/sys/vm/drop_caches
> 
> will first drop the page cache and then drop_slab()

Then that's the problem of "echo 3 > /proc/sys/vm/drop_cache" itself. It invokes other shrinkers as well (if considered an issue), need to be tweaked in the mm.

Best,
Wei