Re: [PATCH RFC] virtio_balloon: conservative balloon page shrinking

From: David Hildenbrand
Date: Thu Feb 06 2020 - 04:49:40 EST


On 06.02.20 10:44, Wang, Wei W wrote:
> 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.

In short, I don't like this approach as long as a drop_slab() can
deflate the whole balloon and don't think this is the right approach then.


--
Thanks,

David / dhildenb