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BP1021 Microsoft SQL Server 2008 Backup and Restore using Dell EqualLogic 17
Impact of full backup & verify
Figure 13 shows an increase in CPU utilization at the SQL production server during full backup and
verify. The average CPU utilization percentage increased from 1.7% to 13% during backup and 1.7% to
10% during verify. As expected, we saw a significant increase in CPU load on the system during the
time that the backup utility was creating the backup.
Figure 13 Impact on CPU utilization during full backup and verify
Figure 14 highlights the increase in application response time (measured at QBMF) during the backup
and verify period. As shown, we noticed a 77% increase in the application response time. This is
because the backup was taken while user transactions were running on the same database. This is a
measure of the average response times incurred by SQL transactions submitted by the simulation tool
(QBMF). Because of the smaller user load used in the test configuration, the response time changes
reported here are in few milliseconds. However, the application response times may change drastically
during full backup while running heavy user load along with heavy use of production SQL server’s
resources.
Figure 14 Impact on application response time during full backup and verify