Re: Fwd: Very slow performance when enabling tierd storage with SSD

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Thanks for the help, see below:

On Sat, Sep 3, 2016 at 11:41 AM, Mohammed Rafi K C <rkavunga@xxxxxxxxxx> wrote:
Files created before attaching hot tier will be present on hot brick until it gets heated and migrated completely. During this time interval we won't get the benefit of hot storage since the files are served from cold brick.
The issue I'm having is that when the hot tier is added read from the volume drops from 150MB/s (no tier) to 2-10MB/s (tier added). I experienced this issue for a while even after the hot brick reached 90% capacity, so many files were promoted.
I detached the hotbrick and verified there weren't any files left over, and the performance was still effected.
It was only until I committed the detach that throughput returned to 150MB/s.

Reattaching the hot tier immediately caused the issue to return until the tier was again detach-committed


For smallfiles (order of kbs), We are experiencing some performance issue mostly with  EC (disperse ) volume.

Follow up questions,
What is the volume type ? and version of glusterfs ?
The volume is a 2x replica on btrfs bricks that are luks encrypted. 2048K GPT offset for 1st partition . Gluster 3.8.3, built aug 22 running on Centos.

Does reread gives an equal performance when it hits the server ?
reading any files with hot tier results in 2-10MB/s (node mounted volume via localhost6:/volume), reading them again any number of times does not improve performance
 
Have you done any rename for those files ?
Some files have been renamed, however the 10GB test file has not it is the original name/copy


_______________________________________________
Gluster-users mailing list
Gluster-users@xxxxxxxxxxx
http://www.gluster.org/mailman/listinfo/gluster-users

[Index of Archives]     [Gluster Development]     [Linux Filesytems Development]     [Linux ARM Kernel]     [Linux ARM]     [Linux Omap]     [Fedora ARM]     [IETF Annouce]     [Bugtraq]     [Linux OMAP]     [Linux MIPS]     [eCos]     [Asterisk Internet PBX]     [Linux API]

  Powered by Linux