Page File on SAN ???

[pmac22]

Hey all,

Should the page file reside on a SAN partition?

Ideally, you'd like to create a page file the same size as RAM on the boot partition for troubleshooting. Then I'd like to create another page file to reside on fast disks (obviously, we'd want as much RAM as possible so we don't need a page file).

My storage admin says that it should NOT reside on SAN disks because it will affect the performance of the SAN because of the way a page file will write and be read from the SAN cache.

Any thoughts?

Thank you!
PM.

 

[p5wizard]

Depends on how big the SAN server's cache is and what type/speed (rpms) the disks at the SAN server's backend are and what the SAN speed is.


HTH,

p5wizard

 

[pmac22]

Thanks p5wizard.

It's a EMC Symmetrix SAN with 128GB of Cache and 50TB of storage.

 

[p5wizard]

FC disks? rpm speed?
2 Gbit/s SAN?
4 Gbit/s SAN?

But if your SAN guy/gal says NOGO, I wouldn't go 'round his/her back and still put the pagefile on a SAN LUN without him/her knowing.

That being said, I put AIX servers with all their OS data and PGSP on a SAN with far less GB of cache (SAN at 4Gbit/s with at the server's backend FC disks of 146GB at 1.5Krpms)


HTH,

p5wizard

 

[jjjon]

I've seen problems(bluescreen) with Windows hosts with SAN-based Page Files when the host happened to be in the middle of a paging operation during a Sym code load.
Saying that I've also seen many servers operate with the page file on SAN disk with no issues.

J

 

[pmac22]

p5wizard,

The Disks are 15K fiber 4GB. I just went ahead and created a page file on the boot part (C:\) and left the SAN part alone, for now.

Thanks for the info jjjon, I actually have been running a few systems with their page files on SAN parts without issue.

I really wanted to know if there was an actual technote or evidence stating that SAN performance is negatively impacted by a page file (which I find hard to believe). I can see issues if the page file was on the boot part and it was booting from SAN (and something hiccupped) but we're not booting from SAN right now.

Thanks again for your input!
PM