Snapshot size question

bublik — Wed, 16 Nov 2011 17:40:11 GMT

Hi,

I extracted this data from mgrClientBinMon.log file

snapshot 'vmfs_11_Sch_SS_2.20' id=10243 read_only client_type='manager' length=500.0GB actual=10.5GB

When it is reporting length... What does this mean, size of the actual volume or snapshot cannot grow beyond this size or something else?

Also I have thick provisioned volume:

Daily snapshot

snapshot 'vmfs_09_Sch_SS_1.168' id=10127 read_only client_type='manager' length=750.0GB actual=1.02GB

Monthly

snapshot 'vmfs_09_Sch_SS_3.5' id=8891 read_only client_type='manager' length=750.0GB actual=650.3GB

why would actual size be different for that much?

Re: Snapshot size question

bryan_hadzik — Wed, 23 Nov 2011 17:28:06 GMT

Length is the reported size of the volume or snapshot. The largest it could grow to. Actual is the real amount of blocks changed in that snapshot.

The reason you can have such a large difference between the two is that most likely your monthly snapshot is the oldest snapshot. When using snapshots, the oldest snapshot contains almost all the data. the newer snapshots, and the volume itself, are only new data since the oldest snapshot.

topic Snapshot size question in StoreVirtual Storage

Snapshot size question

Re: Snapshot size question