Hi,

So here is the story, we have a PS6000e unit where we have configure bunch of volumes, this volumes are mapped by iSCSI to server Dell PowerEdge R610 with Linux CentOS on it.

And here is the problem performance of two volumes are significantly lower than others. !!!

I was doing performance tests using command:

hdparm -t /dev/mapper/stNO--ACPR--MFR-stNO--ACPR--SSC.vol

The physical and network config looks like that:

Slow volumes are MFR and SSC, the rest are kind of OK. Here on picture I placed only two "good" volumes pointing that volume size doesn't matter.

Here are the results:

I don't know is it visible but for slow volume I get typically:

/dev/mapper/stNO--ACPR--MFR-stNO--ACPR--MFR.vol

SGR01

Timing buffered disk reads: 80 MB in 3.04 seconds = 26.29 MB/sec

For this ones which behave normal:

/dev/mapper/stNO--ACPR--MSF-stNO--ACPR--MSF.vol

SGR01

Timing buffered disk reads: 208 MB in 3.02 seconds = 68.80 MB/sec

Difference is more than two times, but the config , network all is the same.

HELP ! Do You guys have any ideas why two volumes behave so weird??