On Wed, May 15, 2019 at 2:32 PM Nicolas Ecarnot <nicolas@ecarnot.net> wrote:
This can happen when using thin provisioned disks on block storage (iSCSI, FC). We provision such disk with 1G, and and extend the disk (add 1G) when it becomes too full (by default, free space < 0.5G).
If we fail to extend the disk quick enough,
"quick enough" -> Is there some place where this threshold can be configured?
Hi, it is some time I don't go into it, because I anyway tend to use preallocated disks on block storage, but at 4.0, 4.1 time, when using thin dsks, the parameters and their tested values were these in vdsm.conf section [irs] or in some other file such as /etc/vdsm/vdsm.conf.d/50_thin_block_extension_rules.conf [irs] # Together with volume_utilization_chunk_mb, set the minimal free # space before a thin provisioned block volume is extended. Use lower # values to extend earlier. volume_utilization_percent = 20 # Size of extension chunk in megabytes, and together with # volume_utilization_percent, set the free space limit. Use higher # values to extend in bigger chunks. volume_utilization_chunk_mb = 8192 Crosscheck in 4.2/4.3. Also, I remember I had problems in RHV 4.2 and RHVH hosts trying to customize vdsm.conf, but I didn't deal much with it because I decided then to use preallocated and not use anymore those parameters. HIH investigating more, Gianluca