I had been experimented with adding a separate log drive to my pool. And I get the following data after 15 days and 5 hours.
Note that the bold line above implies there are at least 45G data written onto the ZIL. But this pool is mainly for browsing and BT-ing. It does not do any NFS sharing. I had so far identified a few activities that may cause writes on the ZIL. The BT client net-p2p/transmission, file extraction, writing of logs, and the flushing of browser cache of www/firefox. I had now changed the sync property to disabled on a few filesystems. I know that sync is good for filesystem consistency, but on a filesystem that only contains downloaded files this should not cause any lasting damage. However, I would still like to know what other activities will lead to writing on ZIL?
PS. I remember before I added a separate log drive, there were times when I extracting a large archive, it would stalled for a second before finished. I can now confirm that this is indeed happening as now I had seen the size of used space on the log drive grew to a few hundred MB in such case. And after a few minutes, it would go back to around 1 MB.
Code:
$ zpool iostat -v
capacity operations bandwidth
pool alloc free read write read write
---------- ----- ----- ----- ----- ----- -----
myzfs 1.11T 4.33T 6 8 847K 520K
raidz2 1.11T 4.33T 6 8 847K 484K
gpt/akjc - - 2 2 145K 126K
gpt/0773 - - 2 2 173K 126K
gpt/6062 - - 1 2 112K 126K
gpt/2651 - - 1 2 129K 126K
gpt/gvkc - - 2 2 174K 126K
gpt/ja7h - - 2 2 129K 126K
logs - - - - - -
[B]gpt/log0 1.41M 4.97G 0 0 0 36.3K[/B]
cache - - - - - -
gpt/cache0 104G 24.7M 19 0 2.40M 90.3K
gpt/cache1 109G 24.9M 20 0 2.44M 90.6K
---------- ----- ----- ----- ----- ----- -----
ssdzfs 2.63G 7.31G 0 0 13.1K 619
gpt/ssd1 2.63G 7.31G 0 0 13.1K 619
---------- ----- ----- ----- ----- ----- -----
Note that the bold line above implies there are at least 45G data written onto the ZIL. But this pool is mainly for browsing and BT-ing. It does not do any NFS sharing. I had so far identified a few activities that may cause writes on the ZIL. The BT client net-p2p/transmission, file extraction, writing of logs, and the flushing of browser cache of www/firefox. I had now changed the sync property to disabled on a few filesystems. I know that sync is good for filesystem consistency, but on a filesystem that only contains downloaded files this should not cause any lasting damage. However, I would still like to know what other activities will lead to writing on ZIL?
PS. I remember before I added a separate log drive, there were times when I extracting a large archive, it would stalled for a second before finished. I can now confirm that this is indeed happening as now I had seen the size of used space on the log drive grew to a few hundred MB in such case. And after a few minutes, it would go back to around 1 MB.