slow performance nas device iscsi

how many disks, what type of disks, what RAID configuration?

what network configuration?

your ESXi datastore configuration is not as fast as it could be, because you are using RAID 1 and 5.

Do you have a BBWC enabled for read and write cache?

Hanccocka; for the server ?

Enterprise disks 2 x 146 gig 10 k (raid1) 3 x 146 gig (10k) raid 5. BBWC 256 mb..

Do you mean enabled in bios or where ?

and the NAS?

You would be better with a single RAID 10 array of 5 x 146 10k disks, more IOPS, than what you've got.

Normally another person told me to have 2x146 GB for the config (vsphere) and 3 x146 gig for the datastore ? But 5 in stead of 30 mb backup time in unnessesary !

When I copy a file from the NAS to a physical machine, I get 40 mb p/sec

Who ever that person, was, did not know how to calculate IOPS per ARRAY, or more disks = more spindles = more performance.

and to be honest, it would be far more beneficial to have ESXi 4.1 installed on USB, saving two expensive 146GB disks for the OS.


Here is the VMware KB on installing 4.1 on USB/SD:
http://kb.vmware.com/kb/1020655

Here is the VMware KB on installing 5.0 on USB/SD:
http://kb.vmware.com/kb/2004784

the G6, has onboard USB flash connector for embedded installation of ESXi.

I was after the spec of the NAS, disks etc

I am sorry, my mistake it is a dl380 g5. I cannot find in vcenter the bbwc controller. I only see P400 controller.

The disks from the qnap 459 pro plus are: Seagate ST2000NM0011 SN02 2 TB HIGH end enterprise disks 7200 rpm. 6G.

The networkcards are gigabit and teamed. Also jumbo frames are on.

To give you an idea of current Max IOPS, assuming 100-140 IOPS per 10k disk

RAID 1 - 2 disks - Total IOPS = (140 IOPS x 2 disks)/(.67 + 2*.33)) = 210
RAID 5 - 3 disks - Total IOPS = (140 IOPS x 3 disks)/(0.67+4*.33)) = 210

RAID 10 - 5 disks - Total IOPS = (140 IOPS x 5 disks)/(0.67+4*.33)) = 526

So you current IOPS per Raid 1 and Raid 5 array are 210!

If you had RAID 10 all 5 disks, you would have double the IOPS per datastore for vSphere 4.0.

How many disks in the Qnap?

4 in total

can you make speeds per second by the iops value ?

And do you know where I can find the bbwc witout opening or shutdown the machine?

See here

http://www.ssdfreaks.com/content/599/how-to-convert-mbps-to-iops-or-calculate-iops-from-mbs

What RAID is in use on NAS?

Also raid 5. When I copy a file from the nas tot my local laptop, I have 30/40 mb/s

Best thing to do, is Shutdown the Server, reboot using the SMart Array CDROM, run the Array Configuration utilities, if you cannot configure the Write and Read %, you do not have one!

other than that's it's plugged into the motherboard, and you'll see the cache module.

Can I also use smartstart to see diagnostics ?

RAID 5 poor for read and write, as detailed above. A write Penality of 4, compared to RAID 10, which has a write penality of 2.

So, you are not getting the max out of your NAS, but with Four disks, SATA 7,200rpm 30/40 MBps is rather slow.

iSCSI Performance to a "homemade NAS"

two disks - 84.5 MB/s Write,  150 MB/s Read
four disks - 196 MB/s Write, 276 MB/s Read
eight disks - 212 MB/s Write,  287 MB/s Read

all disks are SATA II, 7,200rpm, cheap disks.

Diagnostics of what?

Extra thing to notice is that last month I added 3 x 600 GB disks into the DL380 G5. The performance of those disks (10k 6G enterprise) are so SLOW ! I WHen I want to migrate the vms of the raid 5 (146 GB) disks and copy them to the 600 GB disks sometimes it WON't migrate them. Maybe this has also to do with the problems ?

diagnostic of BBWC controller yes or no

1) Did you see my extra notice ? Is there a reason for that slow performance of the 600 GB disks ?

2) I also have A DL380 G6 2 x146 GB raid1, 3 x146 GB raid5, 3 x 300 GB raid5. 512 MB BBWC controller in it. I wanted to try to swop all the disks from the old DL380 G5 to the new DL380 G6 (because the P400 controller is the same), but NO LUCK. It cannot find a datastore anymore.I thought it always worked?

ps: the disks in the qnap are CONSTELLATION ES 7200.1 2TB , 179 euro e piece! (not cheap to me)

Get a BBWC module installed!

You should able to move RAID array between servers, if you use the same slots.

As for your disks, yes there are not cheap, but I was stressing, that the disks I've purchased are 31 GBP each, and peform just as well.

Yours are enterprise disks, and will probably last longer, have a higher MTBF, but what the heck, I've got eight cheapy disks, that are cheap to replace if they fail!

Make sure BBWC is configured correctly for Write.

Hanccocka. Thank you very much for your answers.

You are really a genius !

Is it not better for me to change all over to the DL380 G6 (performance etc.) ?

What is your oppinion ?

And last question; if there is a bbwc controller; I have to configure it in the array config utility ?

G5/G6 performance difference, in processors maybe, but the storage system, is mostly the same.

Yes, BBWC is configure in the ACU.

Best thing to do, is Shutdown the Server, reboot using the SMart Array CDROM, run the Array Configuration utilities, if you cannot configure the Write and Read %, you do not have one!

Select Array, and Configure, and the option is there.

Hanccocka is a real expert in explaining technical issues.

Thanks for you patience.

Checkout this Discussion, with an EE user and his BBWC Experience!

http://www.experts-exchange.com/Software/VMWare/Q_27269019.html

"@touch-base Quoted

"Oh My God

What a difference !    

Both copies of 12 Gb now down to 3 mins (previously 18 and 25 mins).  
And that's from NFS to local datastore

Local to Local - just 2.5 minutes.  Amazing

Thanks Hancoccka"