Hi Jeff,
just remember: system=... changes priority of system vs. user _in this volume_ Use this if users are working on this vol and are impacted (e.g. the source vol).
Use the volume _level_ priority to prioritize between volumes, either giving higher priority to volumes being used (recommended), or by giving lower priority to the SnapMirrored volumes.
But beware: if you have 50 vols, they will all be in the default bucket (prio Medium=50) with possibly lower combined prio (effectively prio=*1* for every volume in the default bucket) than the 2 SnapMirror vols (source & destination, e.g. VeryLow=*8*).
Therefore you better use *priority set default option=value [option=value...] * The /priority set default/ command manages the default priority policy, which is applied to volumes without any specific priority policy. The following options may be specified: *level *Set the priority level for operations are sent to the volume when compared to other volumes. The value might be one of VeryHigh, High, Medium, Low, VeryLow, or a numeric value from 8 (VeryLow) to 92 ( VeryHigh). A volume with a higher priority level receives more resources than a volume with a lower priority level. The default value is Medium. *system* Set the relative priority for system-related operations (such as *SnapMirror *transfers) that are sent to the volume when compared to user operations that are sent to the volume. The valuemight be one of VeryHigh, High, Medium, Low, VeryLow, or a numeric value from 4 (VeryLow) to 96 (VeryHigh). The default value is Medium.
Also be aware that system operations include also things like WAFL-tree updates (metadata...). So if you observe negative effects (e.g. in a high-file-count volume), give this volume a higher system priority or switch priority off when not needed.
HTH
Sebastian
On 01.08.2013 10:04, Jeff Cleverley wrote:
Sebastian,
I had not thought about the priority option. I'll see if it makes sense tomorrow. The slowness seems to affect access to the entire filer. Changing the system priority to low on the source and destination volumes might do the trick though. Thanks for the idea.
Jeff
On Thu, Aug 1, 2013 at 12:58 AM, Sebastian Goetze <spgoetze@gmail.com mailto:spgoetze@gmail.com> wrote:
Hi Jeff, AFAIK as previously mentioned, only _network_ speed is affected. But did you think of the *priority *command? There you can change relative (!) priorities, e.g. system (-> SnapMirror) vs. user. *priority set volume /prodvol /level=high system=low* Set the priority scheduling policy for volume /prodvol /to /high /compared to other volumes. Also prioritize system operations for the volume /low /compared to user operations on the same volume. These options are enabled by this operation if *priority on* has been previous issued. So you would set 'level=high' on the volumes where the users are impacted and 'system=low' and maybe "level=low" (if the source isn't the one where the users are impacted) to the volumes involved in the SnapMirror. Don't forget to set 'priority on'. And maybe 'priority off' after the snapmirror is through if you want to go back to the previous behavior. HTH (Hi Oldtimers, still know this one? - Hope That Helps...) Sebastian On 01.08.2013 07:15, Jeff Cleverley wrote:I did try different positions for the -k. It didn't seem to matter. Jeff On Wed, Jul 31, 2013 at 8:45 PM, steve klise <sklise@hotmail.com <mailto:sklise@hotmail.com>> wrote: I am not sure, but you may want to change your syntax to put the -k before the -S; Not sure if that really matters, but this is what I found in one of the docs.. Good luck. snapmirror update [-k /n/] -S /source_system/:/source_volume/ // [/dest_system/:]/dest_volume/ ------------------------------------------------------------------------ Date: Wed, 31 Jul 2013 19:54:46 -0600 Subject: Snapmirror throttle not working From: jeff.cleverley@avagotech.com <mailto:jeff.cleverley@avagotech.com> To: Toasters@teaparty.net <mailto:Toasters@teaparty.net> Greetings, I'm running 8.1.2P4, 7-mode on some 6290s.а I need to do some snapmirrors to re-balance some disk space.а The -k option to throttle the transfer doesn't seem to be having any effect.а I've tried modifying the placement of the -k but it doesn't seem to matter.а I also tried to modify it after it was running and it doesn't seem to help either.а Here is the command I'm running: snapmirror initialize -S sm15_3 -k 10000 new_sm15_3 If I'm understanding correctly, this should be allowing 10MB/s. The source and destination are on the same file system.а Here is a cut of a sysstat 3 after starting it: аCPUаааа NFSааа CIFSааа HTTPаааа Netаа kB/sааа Diskаа kB/sааа Tapeаа kB/sа Cache ааааааааааааааааааааааааааааааааа inааа outааа readа writeааа readа writeааа age 73%аааа 598аааааа 0аааааа 0ааа 2091 349080а 338016ааа 271аааааа 0ааааа 0аааа 7 а71%ааа 1019аааааа 0аааааа 0ааа 2046 319892а 324019а 13114аааааа 0ааааа 0аааа 0s а71%ааа 2800аааааа 0аааааа 0ааа 3880 330527а 343528а 17379аааааа 0ааааа 0аааа 7 а69%ааа 1440аааааа 0аааааа 0ааа 3405 330279а 392647а 22343аааааа 0ааааа 0аааа 0s а87%ааа 1614аааааа 0аааааа 0ааа 2128 320151а 607753 168553аааааа 0ааааа 0аааа 0s а87%аааа 827аааааа 0аааааа 0ааа 5652 244701а 584436 371689аааааа 0ааааа 0аааа 0s а91%аааа 897аааааа 0аааааа 0ааа 4242 344072а 680454 386373аааааа 0ааааа 0аааа 0s As you can see, the disk read/write counts go way up.а This is causing some noticeable latency in the nfs access for clients.а While I really like the new hardware can pump data around, I need to be able to control it. What am I doing wrong? Thanks, Jeff -- Jeff Cleverley Unix Systems Administrator 4380 Ziegler Road Fort Collins, Colorado 80525 970-288-4611 _______________________________________________ Toasters mailing list Toasters@teaparty.net <mailto:Toasters@teaparty.net> http://www.teaparty.net/mailman/listinfo/toasters -- Jeff Cleverley Unix Systems Administrator 4380 Ziegler Road Fort Collins, Colorado 80525 970-288-4611 _______________________________________________ Toasters mailing list Toasters@teaparty.net <mailto:Toasters@teaparty.net> http://www.teaparty.net/mailman/listinfo/toasters-- Jeff Cleverley Unix Systems Administrator 4380 Ziegler Road Fort Collins, Colorado 80525 970-288-4611