Hello everyone,
Is there anyone having experience to try to tune Kernel RBD device by changing 
scheduler and other settings?

Currently we are trying it on RHEL 7.1 bundled rbd module, to change the 
following setting under /sys/block/rbdX/queue:
1) scheduler: noop vs deadline, deadline seems better
2) nr_requests: default 128, tried 64 & 256 & 1024, and no clear difference 
between different value
3) rotational: as a network based device, should set to 0 for rbd?  Tried and 
no clear difference between different value
4) read_ahead_kb: default 128, tried 4096 will be much better but also seen 
many extra network bandwidth used

Now trying to have a plan to measure performance change on iops, throughput and 
side-effect in a quantitative way, and would like to know if anyone can share 
experience if there is already some optimal setting and if any other parameter 
I should try, like the tunable parameters tuning able for deadline.

Thanks in advance,



Luke

MYCOM OSI
<http://www.mycom-osi.com>

________________________________

This electronic message contains information from Mycom which may be privileged 
or confidential. The information is intended to be for the use of the 
individual(s) or entity named above. If you are not the intended recipient, be 
aware that any disclosure, copying, distribution or any other use of the 
contents of this information is prohibited. If you have received this 
electronic message in error, please notify us by post or telephone (to the 
numbers or correspondence address above) or by email (at the email address 
above) immediately.
_______________________________________________
ceph-users mailing list
ceph-users@lists.ceph.com
http://lists.ceph.com/listinfo.cgi/ceph-users-ceph.com

Reply via email to