You need to make sure SSD O_DIRECT|O_DSYNC performance is good. Not all the 
SSDs are good at it..Refer the prior discussions in the community for that.

<< Presumably as long as the SSD read speed exceeds that of the spinners, that 
is sufficient.
You probably meant write speed of SSDs ? Journal will not be read in the IO 
path , it will be read only during journal replay at the time of OSD restart..

Thanks & Regards
Somnath

-----Original Message-----
From: ceph-users [mailto:ceph-users-boun...@lists.ceph.com] On Behalf Of 
Lindsay Mathieson
Sent: Friday, February 26, 2016 4:16 PM
To: ceph-users@lists.ceph.com
Subject: [ceph-users] SSD Journal Performance Priorties

Ignoring the durability and network issues for now :) Are there any aspects of 
a journals performance that matter most for over all ceph performance?

i.e my inital thought is if I want to improve ceph write performance journal 
seq write speed is what matters. Does random write speed factor at all?

Presumably as long as the SSD read speed exceeds that of the spinners, that is 
sufficient.

--
Lindsay Mathieson

_______________________________________________
ceph-users mailing list
ceph-users@lists.ceph.com
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com
PLEASE NOTE: The information contained in this electronic mail message is 
intended only for the use of the designated recipient(s) named above. If the 
reader of this message is not the intended recipient, you are hereby notified 
that you have received this message in error and that any review, 
dissemination, distribution, or copying of this message is strictly prohibited. 
If you have received this communication in error, please notify the sender by 
telephone or e-mail (as shown above) immediately and destroy any and all copies 
of this message in your possession (whether hard copies or electronically 
stored copies).
_______________________________________________
ceph-users mailing list
ceph-users@lists.ceph.com
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com

Reply via email to