names and wants to sort them by name, ie. when executes:
# zfs list -t snapshot -o name -s name
Because only name is needed we don't have to read all snapshot properties.
Below you can find how long does it take to list 34509 snapshots from a single
disk pool before and after this change with cold and warm cache:
before:
# time zfs list -t snapshot -o name -s name > /dev/null
cold cache: 525s
warm cache: 218s
after:
# time zfs list -t snapshot -o name -s name > /dev/null
cold cache: 1.7s
warm cache: 1.1s
MFC after: 1 week
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