On 2013-4-11 0:46 , Peta Thames wrote:
Hi all,
Has anyone seen this pattern in a sysstat before?
TOASTERa> sysstat -u 1
[...]
Looks like there is something wrong with your disks. The filer is trying desperately to write, but it's unable to get any bandwidth to the disks. The troubles are over as soon as it can get the bandwidth to disk back. Nothing in the logs about a stuck fibrechannel maybe?
You might get more info from a 'statit' run... and/or open a trouble ticket via NOW.
... and back to normal.
Looking in Perf Advisor, it was during an extremely short, sharp latency spike that impacted every volume on every aggregate at exact the same time. It was the fourth of four spikes that had happened a few minutes apart during the previous 20 mins.
It looks like the NVRAM flush got stuck somehow but I have no idea what would cause that.
We're running ONTAP 8.0.2 7-mode on a very busy FAS3170.