I see this in my dmesg log
EXT4-fs (md1): re-mounted. Opts: commit=0 EXT4-fs (md2): re-mounted. Opts: commit=0 EXT4-fs (md3): re-mounted. Opts: commit=0
I think that means that dealloc is disabled? does mdadm not support dealloc?
Unix & Linux Stack Exchange is a question and answer site for users of Linux, FreeBSD and other Un*x-like operating systems. It only takes a minute to sign up.Sign up to join this community
mdadm supports dealloc.
commit=sec is the time, the filesystem syncs its data and metadata. Setting this to 0 has the same effect as using the default value 5.
So I don't get the link between mdadm and commit=0 in your question?
commit=nrsec Sync all data and metadata every nrsec seconds. The default value is 5 seconds. Zero means default.
New drives unload heads. Would then need base on commit size and run the risk of loosing 10 min of work to save wear and tear on disc.