Areca vs. ZFS performance testing.
andrew at modulus.org
Fri Jan 9 18:38:55 PST 2009
ZFS does not require battery-backed disk cache, as long as disks and
controller flush their cache when they are told to by the OS.
Then ZFS only issues sync/flush commands for the ZIL (transaction log),
but majority of I/Os are free to sit in cache to complete when they are
ready. Data that is not fsync()'d by the application may be lost on
power outage, but stuff like databases do fsync() so they are protected.
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