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Unisphere for VMAX: read RT, write RT, and response time
My customer is using Navisphere for vmax to analyze some performance issue on his VMAX 200K.
He was interested in the response time for a specific storage group, and found 3 diferentes metrics:
- read RT (ms)
- write RT (ms)
- response time (ms)
The problem is that graphic of response time (ms) looks like read RT graphics, but does not includes the behavior of write RT (ms) which has a peak of 10ms.
Could you help me to explain this?
PedalHarder
465 Posts
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April 2nd, 2018 18:00
The Response Time graph is a weighted average of the read and write times. If you have lots of reads relative to writes, it is the read response time value that will dominate the Response Time graph.
Look at the read and write counts to illustrate the point.
Jianyun_e442cb
56 Posts
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April 2nd, 2018 18:00
yes there must be just a few writes but most IOs are reads.