On Wed, May 10, 2023 at 9:09 AM Zhang, Cathy <cathy.zhang@xxxxxxxxx> wrote: > > [...] > > > > > > > > Have you tried to increase batch sizes ? > > > > > > I jus picked up 256 and 1024 for a try, but no help, the overhead still exists. > > > > This makes no sense at all. > > Eric, > > I added a pr_info in try_charge_memcg() to print nr_pages if > nr_pages >= MEMCG_CHARGE_BATCH, except it prints 64 during the initialization > of instances, there is no other output during the running. That means nr_pages is not > over 64, I guess that might be the reason why to increase MEMCG_CHARGE_BATCH > doesn't affect this case. > I am assuming you increased MEMCG_CHARGE_BATCH to 256 and 1024 but that did not help. To me that just means there is a different bottleneck in the memcg charging codepath. Can you please share the perf profile? Please note that memcg charging does a lot of other things as well like updating memcg stats and checking (and enforcing) memory.high even if you have not set memory.high.
