On Mon, Jul 24, 2017 at 5:11 PM, Raghavendra G <raghavendra@xxxxxxxxxxx> wrote:
On Fri, Jul 21, 2017 at 6:39 PM, Vijay Bellur <vbellur@xxxxxxxxxx> wrote:On Fri, Jul 21, 2017 at 3:26 AM, Raghavendra Gowdappa <rgowdapp@xxxxxxxxxx> wrote:Hi all,
We've a bug [1], due to which read-ahead is completely disabled when the workload is read-only. One of the easy fix was to make read-ahead as an ancestor of open-behind in xlator graph (Currently its a descendant). A patch has been sent out by Rafi to do the same. As noted in one of the comments, one flip side of this solution is that small files (which are eligible to be cached by quick read) are cached twice - once each in read-ahead and quick-read - wasting up precious memory. However, there are no other simpler solutions for this issue. If you've concerns on the approach followed by [2] or have other suggestions please voice them out. Otherwise, I am planning to merge [2] for lack of better alternatives.Since the maximum size of files cached by quick-read is 64KB, can we have read-ahead kick in for offsets greater than 64KB?I got your point. We can enable read-ahead only for files whose size is greater than the size eligible for caching quick-read. IOW, read-ahead gets disabled if file size is less than 64KB. Thanks for the suggestion.
I added a comment on the patch to move the xlators in reverse to the way the patch is currently doing. Milind I think implemented it. Will that lead to any problem?
Thanks,Vijay
_______________________________________________
Gluster-devel mailing list
Gluster-devel@xxxxxxxxxxx
http://lists.gluster.org/mailman/listinfo/gluster-devel
--Raghavendra G
_______________________________________________
Gluster-devel mailing list
Gluster-devel@xxxxxxxxxxx
http://lists.gluster.org/mailman/listinfo/gluster-devel
--
Pranith
_______________________________________________ Gluster-devel mailing list Gluster-devel@xxxxxxxxxxx http://lists.gluster.org/mailman/listinfo/gluster-devel
