Disk and Tape Device Activity > Drive Throughput
|Article:HOWTO71910|||||Created: 2012-02-08|||||Updated: 2012-02-09|||||Article URL http://www.symantec.com/docs/HOWTO71910|
This report shows the speed (KB/Sec) at which data backups flow through the tape drives. The report uses the "heat map" concept and depicts ranges of speeds (slow to fast) through configurable shades of green color. Reports are generated based on either Hours-of-Day or Days-of-Week. Advanced averaging logic is used to determine the throughput values for each cell in the report. The averaging is done at an image fragment level ensuring granularity and precision in calculations. The reports can be aggregated and filtered at the Tape Library, Media Server, Drive Type, Logical Drive, and Physical Drive levels. The sort options allow intuitive presentation of voluminous data. These reports are important sources of information for performance analysis and capacity planning activities.
As an example on the analysis that can be performed on this report, suppose you look at an LTO4 drive that can run at 120+MB/sec, having a report that shows only 5 -6 MB/sec would indicate that the drives are not even close to being at the maximum capacity. Adding drives in an environment such as this would not impact the backup window. We see a lot of money being spent on new tape drives when customers have trouble pushing tape drives from years ago. If you cannot push an LTO2 drive, then upgrading to an LTO4 will not benefit you (unless you wanted the hardware encryption option of course). These reports are important sources of information for performance analysis and capacity planning activities.
Note that the Drive Throughput report displays data only till 1 A.M. and not till the time when you run the report. This is because OpsCenter collects data for Drive Throughput report once per day at 1 A.M..after midnight. Therefore the Drive Throughput report is only able to report on data up until 1 AM on that day, even when run with a relative timeframe of Previous 24 hours. Similarly if you run Drive Throughput report at 2 P.M. in the afternoon, the reports display data collected till 1 A.M. only.
Symantec recommends that you configure the retention period of error logs in NetBackup as more than 1 day. If the retention period of error logs is less than 24 hours, it may result in data loss for some reports like Drive Throughput.
Figure: Drive Throughput Report shows a sample view of Drive Throughput Report.
You can edit the Drive Throughput report to show or hide the columns that you are interested in. All the columns are shown by default. You can also filter the report to view reports of specific master servers. The following table shows the filters for Drive Throughput report and how you can use these filters to view specific data in the report.
Example of filter usage: You may run the report for specific policy data classification names to view details only for the specific policy classifications. You may run the report for a specific job type like Backup to view drive throughput details for the backup jobs.
Article URL http://www.symantec.com/docs/HOWTO71910