Performance impact due to low aggregate free space
Applies to
ONTAP 9
Issue
- Users or applications are having perfomance issues and ONTAP shows higher latency than normal
- To check the amount of free space available within an aggregate, run the
aggr show-space
cluster shell command. Aggregate free space is low, over 90% used space
Example:
cluster::> aggr show-space -aggregate <aggr_name>
...
Physical Used Percentage: 91%
- Aggregate disk statistics detailing cp-read and write operations can be seen from
statit
on the node shell of a CDOT controller or 7-mode controller with higher cp reads
Example:
::> set advanced
::*> node run -node node_1 statit -b
/* wait 60s */
::*> node run -node node_1 statit -e
...
disk ut% xfers ureads--chain-usecs writes--chain-usecs cpreads-chain-usecs
/aggr1/plex0/rg0:
9d.01.0 36 99.01 0.00 .... . 47.50 62.96 179 51.51 57.25 81
9d.02.0 34 100.39 0.00 .... . 48.92 61.20 162 51.48 57.25 68
1c.03.0 56 206.74 99.04 3.22 2035 40.75 40.53 315 66.95 14.92 338
9d.00.0 73 206.66 100.15 3.22 2993 40.26 40.76 1004 66.25 14.80 640
9d.01.1 73 208.33 101.16 3.31 2918 40.38 40.48 1021 66.79 14.91 643
- EMS Log entry may be present:
[wafl.vol.full:notice]: Insufficient space on volume Cluster1_vol@vserver:0cc56ede-1c58-11e6-XXXX-00a09893e1f7 to perform operation. 8.00KB was requested but only 1.00KB was available.