Re: [Xen-devel] [PATCH v5 0/8] Memory scrubbing from idle loop

["Jan Beulich" <JBeulich@xxxxxxxx>]

>>> On 23.06.17 at 15:11, <boris.ostrovsky@xxxxxxxxxx> wrote:
> On 06/23/2017 05:36 AM, Jan Beulich wrote:
>>>>> On 22.06.17 at 20:57, <boris.ostrovsky@xxxxxxxxxx> wrote:
>>> Deferred:
>>> * Per-node heap locks. In addition to (presumably) improving performance in
>>>    general, once they are available we can parallelize scrubbing further by
>>>    allowing more than one core per node to do idle loop scrubbing.
>> 
>> I don't understand: A per-node lock still calls for just one CPU
>> doing the scrubbing on that node, in order to not congest the
>> lock.
> 
> 
> Is this necessarily true? Maybe not allow all cores on a node to scrub 
> but I'd think having more than one core do the work may be beneficial. 
> Don't forget that actual scrubbing is performed without holding locks. 
> We only grab the lock to find dirty buddies in the heap.

Hmm, true, but then I still don't see the connection between
breaking up the lock and parallelizing scrubbing.

Jan


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
https://lists.xen.org/xen-devel