On 20/06/2024 12:34, David Hildenbrand wrote: > On 20.06.24 11:04, Ryan Roberts wrote: >> On 20/06/2024 01:26, Barry Song wrote: >>> From: Barry Song <v-songbaohua@xxxxxxxx> >>> >>> 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. >> >> I'll try to summarize the thread with Huang Ying by suggesting this test program >> is "neccessary but not sufficient" to exhaustively test the mTHP swap-out path. >> I've certainly found it useful and think it would be a valuable addition to the >> tree. >> >> That said, I'm not convinced it is a selftest; IMO a selftest should provide a >> clear pass/fail result against some criteria and must be able to be run >> automatically by (e.g.) a CI system. > > Likely we should then consider moving other such performance-related thingies > out of the selftests? Yes, that would get my vote. But of the 4 tests you mentioned that use clock_gettime(), it looks like transhuge-stress is the only one that doesn't have a pass/fail result, so is probably the only candidate for moving. The others either use the times as a timeout and determines failure if the action didn't occur within the timeout (e.g. ksm_tests.c) or use it to add some supplemental performance information to an otherwise functionality-oriented test.
