On 16.05.2016 14:18, Peter Zijlstra wrote:
On Mon, May 16, 2016 at 12:36:19PM +0300, Konstantin Khlebnikov wrote:This feature allows to change cpu cgroup weight for a limited time. Cgroup interface: cpu.cfs_reserve_us - reserved time for each cpu.cfs_period_us cpu.cfs_reserve_shares - group weight during reserved time While cfs group consumes reserved cpu time it has different weight, thus it gets different vruntime penalty for that execution. ^ weight | | reserve | shares -------* | | | | | | shares - *-----------------* | | | | 0------|-----------------|-----------> time reserve quota Reserve can work as a "low limit": boost weight for "guaranteed" time, and as a "high limit": give normal weight for a limited time and allow utilize cpu when nobody else needs it.You forgot to explain why I should care about this.
As I told this works as low-limit or high-limit which allow to control cpu time distribution without hard limits and throttling. Present quota/hard limit has well known problems when it throttle task inside kernel where it holds mutexes. Also it's too strict and doesn't allow utilization of unused cpu time. -- Konstantin -- To unsubscribe from this list: send the line "unsubscribe cgroups" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
