We've had some positive results, but I wouldn't call them extreme. The flexshare scheduler only kicks in if the system runs out of resources (CPU etc...) so most of the time it's not actively doing anything. We have had good results on systems that we use for FlexCache . Without FlexShare enabled the flexcache volumes could end up slowing the system down, especially if the remote filer was slow to respond. We set all of our FlexCache vols for caching remote content to a very low priority. Other than that, it helps a little but we still find that one volume (or qtree) can just about monopolize the filer, especially if it's read workload that resides in cache.
If you do enable FlexShare, it is important you set priorities for all volumes. We have had cases where volumes have been missed and it leads to strange performance behavior. We actually run a script to check all of our filers have priority settings on all their volumes.
I had thought of using cron to change priorities at night to enable NDMP backups to get more resources, but we ended up doing away with NDMP backups from the primary filers by using snapvault so it became a non-issue.
--rdp
Rich Payne AMD
-----Original Message----- From: toasters-bounces@teaparty.net [mailto:toasters-bounces@teaparty.net] On Behalf Of Jack Lyons Sent: Wednesday, February 08, 2012 7:21 AM To: toasters@teaparty.net Subject: FlexShare
Has anyone used FlexShare and had extremely positive results. IT seems that the improvement would be minor and misconfiguration could lead to no improvement for intended volumes and degradation for others. From reading, it seems that you need to assign priorities to each volume otherwise the volumes in the default queue will experience degradation.
Would anyone like to share details of how the implemented flexshare and the impact it had on the performance issue they were working to resolve?
Would also like to know if anyone has try to 'schedule flexshare' settings using rsh or api e.g. we want to give higher priorities to certain volumes from 6pm to 11pm nightly.
Thanks Jack _______________________________________________ Toasters mailing list Toasters@teaparty.net http://www.teaparty.net/mailman/listinfo/toasters