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NEURAL_HAM_LONG(-1.00)[-1.000]; MID_RHS_NOT_FQDN(0.50)[]; HAS_REPLYTO(0.30)[pvorel@suse.cz]; R_DKIM_ALLOW(-0.20)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MX_GOOD(-0.01)[]; FUZZY_BLOCKED(0.00)[rspamd.com]; RCVD_VIA_SMTP_AUTH(0.00)[]; ARC_NA(0.00)[]; TO_DN_SOME(0.00)[]; MISSING_XM_UA(0.00)[]; MIME_TRACE(0.00)[0:+]; REPLYTO_EQ_FROM(0.00)[]; RCPT_COUNT_THREE(0.00)[4]; FROM_EQ_ENVFROM(0.00)[]; FROM_HAS_DN(0.00)[]; DKIM_SIGNED(0.00)[suse.cz:s=susede2_rsa,suse.cz:s=susede2_ed25519]; RCVD_TLS_ALL(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; DKIM_TRACE(0.00)[suse.cz:+] X-Virus-Scanned: clamav-milter 1.0.7 at in-5.smtp.seeweb.it X-Virus-Status: Clean Subject: Re: [LTP] [PATCH] ksm: fix segfault on s390 X-BeenThere: ltp@lists.linux.it X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux Test Project List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Petr Vorel Cc: ltp@lists.linux.it, Luiz Capitulino Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ltp-bounces+ltp=archiver.kernel.org@lists.linux.it Sender: "ltp" Hi Li, Luiz, > Luiz Capitulino wrote: > > > I might be a bit too picky:). So I compared the two approaches on a > > > 2 CPUs, KVM, x86_64 system: > > > Per-block checking cost time: > > > real 0m5.862s > > > user 0m1.098s > > > sys 0m1.505s > > > Per-byte checking cost time: > > > real 0m6.819s > > > user 0m2.498s > > > sys 0m1.495s > > > From the data, block-by-block checking can reduce the total execution > > > time by about 14% and reduce CPU usage by more than 35%, especially > > > in user-space calculations. This number may not be large, but considering > > > that tests are frequently run in CI, I think it would be a good thing if we can > > > reduce 1 second each time :). > > Just to make sure I understand: you measured total test run-time, correct? > > How many times did you run it? > > In any case, I'm not sure a 1 second run-time (or even CPU utilization) matters > > that much. You're running test code, you shouldn't expect otherwise unless you > > hit a very bad case (say something taking several hours to complete). > > The trade off is more complex code with bugs that can hide for 10+ years and > > take developer time to debug. Also, higher memory utilization: 's' doubles > > memory utilization per child only to do that check. > Ture, that's why the problem not been find so many years! > > So, I suggest we stick to the simpler code. Or, get it merged now (since it's > > fixing a bug and possibly making the code _faster_) and then you can optimize > > on top later if you like. > Ok, sounds reasonable. > Reviewed-by: Li Wang > @Cyril, @Petr, I vote to merge this one (as it is) before our May release. LGTM. Reviewed-by: Petr Vorel Kind regards, Petr -- Mailing list info: https://lists.linux.it/listinfo/ltp