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charset=us-ascii Content-Disposition: inline In-Reply-To: <20241015213721.3804209-1-shakeel.butt@linux.dev> X-Rspamd-Queue-Id: A73D11A0017 X-Stat-Signature: gyaor341enr5bqfa4tocbxn8xjqtyar4 X-Rspamd-Server: rspam09 X-Rspam-User: X-HE-Tag: 1729029153-718841 X-HE-Meta: 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 ZNnmVAoH 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Tue, Oct 15, 2024 at 02:37:21PM -0700, Shakeel Butt wrote: > The memcg stats are maintained in rstat infrastructure which provides very > fast updates side and reasonable read side. However memcg added plethora > of stats and made the read side, which is cgroup rstat flush, very slow. > To solve that, threshold was added in the memcg stats read side i.e. no > need to flush the stats if updates are within the threshold. > > This threshold based improvement worked for sometime but more stats were > added to memcg and also the read codepath was getting triggered in the > performance sensitive paths which made threshold based ratelimiting > ineffective. We need more visibility into the hot and cold stats i.e. > stats with a lot of updates. Let's add trace to get that visibility. > > Signed-off-by: Shakeel Butt > Acked-by: Roman Gushchin > Reviewed-by: Yosry Ahmed > Cc: Michal Hocko > Cc: Johannes Weiner > Cc: Muchun Song > Cc: JP Kobryn > Cc: Steven Rostedt (Google) > Cc: Andrew Morton Acked-by: Johannes Weiner