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BP1014 Enhancing SQL Server Protection using Dell EqualLogic Snapshot Smart Copies
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snapshot is transactionally consistent with the source database at the time the snapshot is created. A
snapshot will persist until it is dropped.
3.3.1 Time to create a SQL Server snapshot as a function of user load
In the first test we measured how long it took to complete snapshot creation at different simulated
user loads. Test details:
 The same system configuration was used as in the previous section.
 The TPC-C style workload was simulated while varying user load in increments from 100 to
4000 users. (The time to create the snapshot for the 100 user workload was approximately 1
second. This data point is not included in Figure 5.)
 No prior snapshots existed when each of the snapshots in this test was created. For each data
point, we dropped the previous snapshot before creating the next one.
The results of this test are presented in Figure 5.
Figure 5 – Time to create SQL Server snapshots at different user loads
The result of this test clearly indicate that time window required to complete creation of a SQL
Server® database snapshot depends on the system workload at the time the snapshot is created.
3.3.2 Time to create SQL Server snapshots while retaining previous snapshots
In this test we measured the time to create SQL Server® snapshots while the test system was under
load. The goal of this test was to measure the cumulative performance impact on the system during