Re: [PATCH] selftests/mm: Introduce a test program to assess swap entry allocation for thp_swapout

[David Hildenbrand <david@redhat.com>]

On 20.06.24 03:53, Huang, Ying wrote:
> Barry Song <21cnbao@gmail.com> writes:
> 
>> From: Barry Song <v-songbaohua@oppo.com>
>>
>> Both Ryan and Chris have been utilizing the small test program to aid
>> in debugging and identifying issues with swap entry allocation. While
>> a real or intricate workload might be more suitable for assessing the
>> correctness and effectiveness of the swap allocation policy, a small
>> test program presents a simpler means of understanding the problem and
>> initially verifying the improvements being made.
>>
>> Let's endeavor to integrate it into the self-test suite. Although it
>> presently only accommodates 64KB and 4KB, I'm optimistic that we can
>> expand its capabilities to support multiple sizes and simulate more
>> complex systems in the future as required.
> 
> IIUC, this is a performance test program instead of functionality test
> program.  Does it match the purpose of the kernel selftest?

We do have the similar tests at least for ksm (ksm_tests.c) and probably 
others:

$ git grep -l clock_gettime
ksm_tests.c
migration.c
mremap_test.c
transhuge-stress.c


I recall that gup_test.c also measures performance things.

-- 
Cheers,

David / dhildenb