> The storage used in the "Physical" system is EMC VNX.
EMC is SAN which is usually shared - unless you have your own dedicated SAN.
The performance of these machines will vary on a lot of factors. Here's just 3...
1) How heavily contended are they with other teams in your organisation.
Try and get stats from the SAN team on throughput for your machine (ignore IOPS - thats only useful to the SAN team).
2) What underlying hardware do they have in place on the EMCs ?
We have SAN with both hard disks and SSD. The most heavily used disk pages are held on SSD and will be faster than less heavily used pages. On our SAN the difference is SSD page reads are three times the speed of non-SSDs. (During our last SAN move it took 5 days for the performance to improve as our heavily used data moved up to the SSDs)
3) Page size.
What page size is the VNX set to ? Generally SANs are 16k, 32k or 64k. I've found the difference between pages size on Sybase to make a big difference. For optimal performance I think they should match - but for other reasons, we have 16k Sybase pages and 32k disk pages.
Note: Writes to the SAN are completed when they write to the SAN cache so you're unaffected by underlying disks.
On an EMC disk I can see performance vary between 0.5ms per page all the way to 10ms per page.
What are you getting ?
Find a large table, unbind it from the cache - so its all physical reads - and select the top 500,000 rows. Whats the output from set statistics io,time on ?