lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Wed, 03 Apr 2013 13:38:20 +0800 From: Michael Wang <wangyun@...ux.vnet.ibm.com> To: Alex Shi <alex.shi@...el.com> CC: mingo@...hat.com, peterz@...radead.org, tglx@...utronix.de, akpm@...ux-foundation.org, arjan@...ux.intel.com, bp@...en8.de, pjt@...gle.com, namhyung@...nel.org, efault@....de, morten.rasmussen@....com, vincent.guittot@...aro.org, gregkh@...uxfoundation.org, preeti@...ux.vnet.ibm.com, viresh.kumar@...aro.org, linux-kernel@...r.kernel.org, len.brown@...el.com, rafael.j.wysocki@...el.com, jkosina@...e.cz, clark.williams@...il.com, tony.luck@...el.com, keescook@...omium.org, mgorman@...e.de, riel@...hat.com Subject: Re: [patch v3 0/8] sched: use runnable avg in load balance On 04/03/2013 12:28 PM, Alex Shi wrote: [snip] > > but the patch may cause some unfairness if this/prev cpu are not burst at > same time. So could like try the following patch? I will try it later, some doubt below :) [snip] > + > + if (cpu_rq(this_cpu)->avg_idle < sysctl_sched_migration_cost || > + cpu_rq(prev_cpu)->avg_idle < sysctl_sched_migration_cost) > + burst= 1; > + > + /* use instant load for bursty waking up */ > + if (!burst) { > + load = source_load(prev_cpu, idx); > + this_load = target_load(this_cpu, idx); > + } else { > + load = cpu_rq(prev_cpu)->load.weight; > + this_load = cpu_rq(this_cpu)->load.weight; Ok, my understanding is, we want pull if 'prev_cpu' is burst, and don't want pull if 'this_cpu' is burst, correct? And we do this by guess the load higher or lower, is that right? And I think target_load() is capable enough to choose the higher load, if 'cpu_rq(cpu)->load.weight' is really higher, the results will be the same. So what about this: /* prefer higher load if burst */ load = burst_prev ? target_load(prev_cpu, idx) : source_load(prev_cpu, idx); this_load = target_load(this_cpu, idx); Regards, Michael Wang > + } > > /* > * If sync wakeup then subtract the (maximum possible) > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists