2–6 Planning and Design
Hitachi Simple Modular Storage Copy-on-Write SnapShot User’s Guide
2. At the end of the period, convert the data to MB/second, if it is not
already so, and import into a spreadsheet tool. Figure 2-3 shows
collected raw data, in megabytes per second in 10 minute segments.
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Figure 2-3: Raw Data Example in MB/sec
3. Using the copy frequency established earlier, calculate averages over the
collection period. Most spreadsheet tools have an average function. For
example:
If copy frequency is 1 hour, then calculate 60 minute rolling averages
using the values in 6 10-minute intervals.
If copy frequency is 4 hours, then calculate 240 minute rolling averages
using the values in 24 10-minute intervals.
Figure 2-4 illustrates 60-minute rolling averages.
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Figure 2-4: Rolling Averages Calculated Using V-VOL Frequency
Example rolling-average procedure using Excel:
a. In cell C4, type =Average(b2:b7).