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charset=us-ascii Content-Disposition: inline In-Reply-To: X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Rspam-User: X-Rspamd-Server: rspam03 X-Stat-Signature: 6zwohoek5fzi936856pg4wq1g4zqmehn X-Rspamd-Queue-Id: 71DBE180016 X-HE-Tag: 1680202436-25153 X-HE-Meta: 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 cevB/Zvt jwoGqB5j8l1ZGTvXOZwlmZdvMP1Vk8bHJ2hlWNWz/1yoLcQI0aY19ic408LhGWOh2fzdiaqJb3u9IU8yXj5KxnMJOisVkBlB2fktuLpkZ9mWLZ+frDmDKa8fjXojpHzumNEshX/uJ740WOQAJ0RNqSAPgygvPP4zQ+/SF5e70lpr7qUGZykZGuRWWLRLjcX409wTusLCQ0Fq0gMfde4dN+HNKC6rEY0Up14Sb3a+zfwUdGp9e1lwBJ29lEhBzs1+v3FbSwHFXe1v5pTP6a2GeP/AD7D8myCUDj640fDjQ45Nvh3JaBsbYfSZJgA== 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: On Thu, Mar 30, 2023 at 03:28:52PM +0200, Michal Hocko wrote: > > > Is this a best practice documented anywhere or it just happens to be > > > the case with workloads you deal with? > > > > Option 2. However Frederic seems interested in matching the exported > > toggles with the known use-cases classes. > > > > For example, for this guide: > > http://www.comfilewiki.co.kr/en/doku.php?id=comfilepi:improving_real-time_performance:index > > > > Using nohz_full= would be a benefit (and its not being currently set, > > perhaps due to not knowing all the options?). > > > > http://www.comfilewiki.co.kr/en/doku.php?id=comfilepi:improving_real-time_performance:index > > > > > > AFAIU the workloads for which disabling nohz_full= is a benefit are those > > where the switching between nohz full mode and sched tick enabled mode > > and vice-versa (which involve programming the local timer) happens > > often and is therefore avoidable? For example switching between 1 > > runnable task and more than 1 runnable task (and vice versa). > > The patch from Frederic is testing for both. You seem to be arguing to > reduce the test and I still do not understand why. Sure some workloads > (following the above) will likely use nohz_full= as well but does it > make sense to build that expectation into the higher level logic? What > is an actual benefit? Just thinking of simpler code. Feel free to maintain the patch as-is if you see fit.