Questions tagged [dm-cache]
3 questions
2
votes
1 answer
lvmcache/dm-cache writeback cache full performance
I have a SSD writeback cache in front of a HDD, set up through lvmcache (so a dm-cache). When the cache LV is not full (Data% column in lvs < 100.00%), writes go to the cache device (monitored via dstat). However, when the cache LV is full (Data% =…
Albert T
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LVM aggressive read and write cache
I've added a 2 TB RAID1 SSD as a writeback cache to a 10 TB RAID1 HDD using LVM 2.03.11(2) (2021-01-08) like this:
lvcreate --type raid1 --mirrors 1 --nosync -l 100%FREE -n sshd sshd /dev/sdc /dev/sdd
lvcreate --type raid1 --mirrors 1 --nosync -l…
Chris
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What does the Cpy%Sync column of lvs output mean for a cache LV?
I have a host with a single cache LV (~800GB SSD in front of a multi-TB RAID array; write-through mode). I ran a routine scrub on the RAID last night (lvchange --syncaction check). Ever since that completed, the system has been running at 100% I/O…
zwol
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