tdb@
Developer
I've recently built a new server which has a mirrored ZFS pool for its data. Whilst trying to diagnose some performance issues I've come across the following unusual output from zpool iostat:
The first instances shows more bandwidth being used on the disks than on the pool itself. I'm not sure how to interpret this. Does it mean that ZFS is internally doing a lot of activity? The second instance is what I consider to be more normal.
I'd be interested to know what others have seen.
As an aside, in the first instance the file system is pretty slow to respond. Mutt with large maildir folders becomes a nightmare to use :-(
Code:
capacity operations bandwidth
pool used avail read write read write
---------- ----- ----- ----- ----- ----- -----
pool0 93.4G 40.6G 221 0 727K 19.7K
mirror 93.4G 40.6G 221 0 727K 19.7K
ad4s3 - - 61 0 3.70M 19.7K
ad6s3 - - 58 0 3.51M 19.7K
---------- ----- ----- ----- ----- ----- -----
Code:
capacity operations bandwidth
pool used avail read write read write
---------- ----- ----- ----- ----- ----- -----
pool0 91.6G 42.4G 49 0 6.10M 0
mirror 91.6G 42.4G 49 0 6.10M 0
ad4s3 - - 23 0 2.98M 0
ad6s3 - - 25 0 3.14M 0
---------- ----- ----- ----- ----- ----- -----
The first instances shows more bandwidth being used on the disks than on the pool itself. I'm not sure how to interpret this. Does it mean that ZFS is internally doing a lot of activity? The second instance is what I consider to be more normal.
I'd be interested to know what others have seen.
As an aside, in the first instance the file system is pretty slow to respond. Mutt with large maildir folders becomes a nightmare to use :-(