Re: [PATCH V5 04/17] blk-throttle: configure bps/iops limit for cgroup in low limit

From: Tejun Heo
Date: Mon Jan 09 2017 - 12:35:37 EST


Hello,

On Thu, Dec 15, 2016 at 12:32:55PM -0800, Shaohua Li wrote:
> each queue will have a state machine. Initially queue is in LIMIT_LOW
> state, which means all cgroups will be throttled according to their low
> limit. After all cgroups with low limit cross the limit, the queue state
> gets upgraded to LIMIT_MAX state.

As with the previous patch, I don't think it's correct to default to
MAX for LIMIT_LOW and then enforce it. Without specific
configuration, a cgroup should always be above below (so, no latency
requirement) and below max (no hard limiting).

Thanks.

--
tejun