Storage Spaces recovery time
The time needed to recover a failed Storage Spaces depends on the recovery case you deal with (Case I, II, or III),
in other words, what capabilities of ReclaiMe Storage Spaces Recovery you need to use.
If you deal with a Case I recovery, you need ReclaiMe Storage Spaces Recovery just to process
Storage Spaces metadata.
For a Case II recovery it is needed to use the Find drives procedure;
for a Case III recovery you need to execute Deep scan.
Time to process Storage Spaces metadata
When you specify pool member disks and click the Start button,
ReclaiMe Storage Spaces Recovery starts searching the drives for Storage Spaces database records which may take several minutes.
Time of the Find drives procedure
How long the Find drives procedure takes depends on both a particular pool configuration and on CPU power of a PC
running Storage Spaces recovery. Typically, it takes from several minutes to a couple of hours in the worst-case scenario.
Time of the Deep scan procedure
The Deep scan procedure consists of three stages and therefore the total time of the procedure is determined by the sum
of the times ReclaiMe Storage Spaces Recovery spends on each of these stages.
First stage
At this stage, ReclaiMe Storage Spaces Recovery reads and processes data from all the pool member disks.
With an average disk read speed of about 50 - 60 MB/s (SATA connection) it takes approximately 12 hours to
just read data off a 2 TB drive. Processing speed depends mainly on CPU power of a PC running recovery.
Storage Spaces recovery running on a PC with a recommended configuration (one CPU core per two drives)
takes ten hours for a pool created on four drives of 2 TB. Thus, it takes about a day just for the first stage.
Note that the more drives in the pool and the less CPU power, the more time the first stage takes.
Transition between the first and the second stages
Transition time between the first and the second stages depends directly on the amount of data collected on the first stage.
It is impossible to predict in advance how long it will take to complete the transition; typical times range from ten minutes to a couple of hours.
Second stage
The second stage requires to read all the data from all the drives in the pool again meaning about a day
for an average size pool.
Third stage
The time to complete the third stage depends on the PC characteristics.
The more CPU power and memory, the faster recovery. Usually, it takes up to fifteen minutes.
Total time of Deep scan
So, for a pool of an average size the Deep scan procedure takes about a couple of days.
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