First off, apologies if I'm not immediately able to relate all necessary information: storage is not my specialism, so it may take some to-ing and fro-ing to provide it
I'm interested in maximising the performance for a single large (~1TB) file read operation.
I have tried various CentOS7, Windows 2012 R2 and Windows 10 clients, connected with a single 8GB FC path to a dedicated 10T NL LUN via an HP StorageWorks 8GB SAN switch.
I've tried reading the file from a P10K with 8G FC ports but the maximum read speed I hit is around 3.2 Gbps.
If I start off another read from the same disk, I also get a 3.2Gbps read operation (as you might expect)
If I start off a third, all three drop to around 2.5Gbps and so on, so it's behaving as though the 8Gpbs bandwidth in this case, is available but that each file operation has a ceiling of 4Gbps.
The P10K has a 4Gbps shelf speed I believe, but the array has multiple shelves with the VVG comprised of disks across multiple shelves (as you'd expect) I think it's running Inform 3.1.2
I've tried the same configuration and test with an 8200, with the same result.
I don't see that it can be client hardware/firmware/software as I get the same result on everything I try.
I plan to fibre a host directly into one of the array ports, to try eliminating the SAN switch as that's a common factor)
I don't see why the 3PAR would be limited to 4G per operation, but maybe it is? I thought it worth comparing the 8200 just because of the newer technology.
If I use an internal NVMe as the read source on the same machines, I can get up to 20Gbps
Thanks for any advice
Darren