Benjamin Kingston
2016-Sep-03 03:46 UTC
[Gluster-users] Fwd: Very slow performance when enabling tierd storage with SSD
Hello all, I've discovered an issue in my lab that went unnoticed until recently, or just came about with the latest Centos release. When the SSD hot tier is enabled read from the volume is 2MB/s, after detaching AND committing, read of the same file is at 150MB/s to /dev/null If I copy the file to the hot bricks directly the write is 150MB/s and read is 500MB/s on the first read, and then 4GB/s on the subsequent reads (filesystem RAM caching) to /dev/null Just enabling tier storage takes the performance to ~10-20IOPS and 2-10MB/s even for local node mounted volume. I don't see any major log issues and I detached and did a fix-layout, but it persists when re-enabling the tier. -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://www.gluster.org/pipermail/gluster-users/attachments/20160902/d038888a/attachment.html>
Mohammed Rafi K C
2016-Sep-03 07:07 UTC
[Gluster-users] Fwd: Very slow performance when enabling tierd storage with SSD
Hi Benjamin, Can you tell us more about your work-load like the file size, size of both hot and cold storage, how the files are created (after attaching the tier or before attaching the tier) , how long have you been using the tier volume, etc. Regards Rafi KC On 09/03/2016 09:16 AM, Benjamin Kingston wrote:> Hello all, > > I've discovered an issue in my lab that went unnoticed until recently, > or just came about with the latest Centos release. > > When the SSD hot tier is enabled read from the volume is 2MB/s, after > detaching AND committing, read of the same file is at 150MB/s to /dev/null > > If I copy the file to the hot bricks directly the write is 150MB/s and > read is 500MB/s on the first read, and then 4GB/s on the subsequent > reads (filesystem RAM caching) to /dev/null > > Just enabling tier storage takes the performance to ~10-20IOPS and > 2-10MB/s even for local node mounted volume. > > I don't see any major log issues and I detached and did a fix-layout, > but it persists when re-enabling the tier. > > > > > _______________________________________________ > Gluster-users mailing list > Gluster-users at gluster.org > http://www.gluster.org/mailman/listinfo/gluster-users-------------- next part -------------- An HTML attachment was scrubbed... URL: <http://www.gluster.org/pipermail/gluster-users/attachments/20160903/55dbb80f/attachment.html>