topic Re: EVA4000 performance path in Disk Enclosures

EVA4000 performance path

Bernhard Mueller — Thu, 22 Dec 2005 07:06:41 GMT

Hi,

how can I find out (as quick as possible) which controller currently owns a certain vdisk of an EVA4K?

Explanation: server is HP-UX using pvlinks, would like to make sure all vdisks are on performance path.

Regards,
Bernhard

Re: EVA4000 performance path

Uwe Zessin — Thu, 22 Dec 2005 07:49:57 GMT

C:\Program Files\Hewlett-Packard\EVA Performance Monitor>evaperf vd

In the "Online To" column.

Re: EVA4000 performance path

Ivan Ferreira — Thu, 22 Dec 2005 08:06:17 GMT

You have to use evaperf. But by default, the VDISK WWID is printed, not the VDISK name. You must create a file called fnames.conf to make the conversion. (See command view user guide).

Re: EVA4000 performance path

Bernhard Mueller — Thu, 22 Dec 2005 09:15:01 GMT

thanks for your help,

can I manually "move" vdisk, i.e. assign it to the other controller?

Regards,
Bernhard

Re: EVA4000 performance path

NathanK — Thu, 22 Dec 2005 09:58:17 GMT

I could be mistaken, but I thought the EVA 4/6/8 were active/active. When I do an evaperf vd it shows the vdisk connected to both controllers.

Re: EVA4000 performance path

Bernhard Mueller — Thu, 22 Dec 2005 10:19:14 GMT

yes it is active on both, however, there should still be a "primary" or "owning" controller which provides the best performance for the respective vdisk.

Regards,
Bernhard

Re: EVA4000 performance path

Uwe Zessin — Thu, 22 Dec 2005 13:26:38 GMT

I haven't tried it on the EVA XL yet, but on the first generation EVAs I was able to change the preferred path in CV-EVA and a scan from the server (WWIDMGR on AlphaServer) did show that the change had happened.

Re: EVA4000 performance path

sdbs — Tue, 10 Oct 2006 03:32:40 GMT

What should be the best performance path setting on EVA4K?
We used the default setting for every VD, but the read hit ratio was too slow. Most of all the read requests were missed from the controller cache.
How we could tune the EVA4K performance ?
Who can help me?
Thanks a lot.

Re: EVA4000 performance path

Tom O'Toole — Tue, 10 Oct 2006 14:05:58 GMT

The cache hit rate itself shouldn't depend on the LUN owning controller.

Are you using evaperf to determine your cache hit rate?

Re: EVA4000 performance path

sdbs — Tue, 10 Oct 2006 20:07:43 GMT

Yes! I got the performance raw data by evaperf utility.

And we used 16 * 146GB 10K-rpm FC disks in two disk shelves.
Just create only one disk group.
Without DR and snapshot.