Hi leo,
On 29 June 2016 at 08:18, Leo Yan leo.yan@linaro.org wrote:
Hi Vincent,
On Fri, Jun 24, 2016 at 05:22:42PM +0200, Vincent Guittot wrote:
[...]
I'm not strong to stick to use this patch but not to set sysctl_sched_migration_cost. The mainly benefit for this patch is after applying this patch, then it will be useful to keep it in the code. Otherwise there have no one place to track this issue anymore.
Or follow your suggestion, I may write one patch to define a special macor like: CONFIG_ENERGY_AWARE_AGGRESSIVE_TASK_SPREAD, after enable this configuration then we set sysctl_sched_migration_cost to 0.
If have any other idea, just free let me know. Thanks.
Such settings are system tuning and don't have to be put in the kernel. They have to be considered like other tunings: cpufreq sampling rate, interruption affinity ...
I agree that we have to track these tunings which have major impact on EAS but kernel doesn't seem to be the best place IMO. Can we create a document like a wiki page in which we can list all settings that impact EAS behavior and what us the preferred value?
It's a good suggestion. I'm not the best one to do this due I have no global view for current working items, but this will be very useful for us to discuss questions on the same page. So I drafted one for EAS check list and known issues tracking: https://wiki.linaro.org/eas-checklist-and-known-issues-tracking
If miss anything, freely let me know or welcome updating in wiki page.
Thanks Leo,
I'm going to have a look
Regards, Vincent
I pretty sure that other tunings (scheduler but not only) impacts EAS but default values might not be the best ones for EAS.
So we could track all if them in one single place
Regards,
return 1;}schedstat_inc(p, se.statistics.nr_failed_migrations_hot); return 0;}
1.9.1