Re: [PATCH 0/3] allow zram to use zbud as underlying allocator

Vlastimil Babka
2015-09-30T15:37:39Z

On 09/25/2015 11:54 AM, Vitaly Wool wrote:
> Hello Minchan,
>
> the main use case where I see unacceptably long stalls in UI with
> zsmalloc is switching between users in Android.
> There is a way to automate user creation and switching between them so
> the test I run both to get vmstat statistics and to profile stalls is
> to create a user, switch to it and switch back. Each test cycle does
> that 10 times, and all the results presented below are averages for 20
> runs.
>
> Kernel configurations used for testing:
>
> (1): vanilla
> (2): (1) plus "make SLUB atomic" patch [1]
> (3): (1) with zbud instead of zsmalloc
> (4): (2) with compaction defer logic mostly disabled

Disabling compaction deferring leads to less compaction stalls? That
indeed looks very weird and counter-intuitive. Also what's "mostly"
disabled mean?