sbumpas
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Disparity between read/write speeds when performing SVMotion
Last night I performed a SVMotion on a VM from a SSD to a 6 disk RAID10. The read/write rates are shown in the attached graphic. Any idea why my read rate would be 1/2 my write rate? It seems to me that, at the very least, they should be equal? How can a disk write faster than the data being read?
710.JPG
710.JPG
theruck
your raid controller uses battery write cache module which is essentially a RAM which has much higher transfer rates than any SSD chips. anyway you can see that these graphs show nothing real and that vmware (and also other vendors) are just giving you something you do not need.
ASKER
The write cache was my first thought, but you can see in the start in the xfer the speeds are much higher - presumably while the cache is in use. Once cache is full, the speeds bottom out (a bit) but the writes are still 2x faster.
What do you mean the graphs "show nothing real"?
What do you mean the graphs "show nothing real"?
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What do you mean the graphs "show nothing real"?
if you want a longer discussion, leave the question to run for longer, for the storage Experts!
if you want a longer discussion, leave the question to run for longer, for the storage Experts!
ASKER
I would love to know more - do I need to repost since I accepted an answer?
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