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Wed, 21 Feb 2024 07:44:09 +0000 (UTC) Received: from dovecot-director2.suse.de ([2a07:de40:b281:106:10:150:64:167]) by imap1.dmz-prg2.suse.org with ESMTPSA id MYn8Fcmp1WV9HAAAD6G6ig (envelope-from ); Wed, 21 Feb 2024 07:44:09 +0000 Date: Wed, 21 Feb 2024 08:44:08 +0100 From: Michal Hocko To: Bixuan Cui Cc: Steven Rostedt , akpm@linux-foundation.org, mhiramat@kernel.org, mathieu.desnoyers@efficios.com, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-mm@kvack.org, opensource.kernel@vivo.com Subject: Re: [PATCH -next v6 0/2] Make memory reclamation measurable Message-ID: References: <20240105013607.2868-1-cuibixuan@vivo.com> <20240220212202.59ddc123@gandalf.local.home> <3d4f44ee-f533-446f-a9e6-7f58afc78d65@vivo.com> Precedence: bulk X-Mailing-List: linux-trace-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <3d4f44ee-f533-446f-a9e6-7f58afc78d65@vivo.com> Authentication-Results: smtp-out2.suse.de; none X-Spamd-Result: default: False [0.39 / 50.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; FROM_HAS_DN(0.00)[]; TO_DN_SOME(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; MIME_GOOD(-0.10)[text/plain]; RCVD_COUNT_THREE(0.00)[3]; DKIM_SIGNED(0.00)[suse.com:s=susede1]; RCPT_COUNT_SEVEN(0.00)[9]; FUZZY_BLOCKED(0.00)[rspamd.com]; FROM_EQ_ENVFROM(0.00)[]; MIME_TRACE(0.00)[0:+]; MID_RHS_NOT_FQDN(0.50)[]; RCVD_TLS_ALL(0.00)[]; BAYES_HAM(-0.01)[45.20%] X-Spam-Level: X-Spam-Flag: NO X-Spam-Score: 0.39 On Wed 21-02-24 11:00:53, Bixuan Cui wrote: > > > 在 2024/2/21 10:22, Steven Rostedt 写道: > > It's up to the memory management folks to decide on this. -- Steve > Noted with thanks. It would be really helpful to have more details on why we need those trace points. It is my understanding that you would like to have a more fine grained numbers for the time duration of different parts of the reclaim process. I can imagine this could be useful in some cases but is it useful enough and for a wider variety of workloads? Is that worth a dedicated static tracepoints? Why an add-hoc dynamic tracepoints or BPF for a very special situation is not sufficient? In other words, tell us more about the usecases and why is this generally useful. Thanks! -- Michal Hocko SUSE Labs