I need help in choosing the right Raid Configuration.

[micromaster]

Hay Guys,

I own a file hosting service and i am kind of not sure what to do with Raid.
My server Configuration is as follow:

HP DL180
Dual Xeon E5620
24 GB ECC DDR3 RAM
12 X 2 TB 7.2 Enterprise Drives
10Gbps Port Speed

No i have Raid Configured to RAID5, and it is a disaster.
I am serving about 30,000 Downloads per day from this server, about 15TB per day.

My current read speed is as follow:

:~# sudo hdparm -t /dev/sda

/dev/sda:
 Timing buffered disk reads: 232 MB in  3.18 seconds =  73.01 MB/sec

I don't know what Raid Configuration should i go with, keep in mind that i need as much space as i can.

Thanks in advance.

[vadonka]

we also have a DL180 server, just a bit less hdd
something is not right with your raid config or drivers because we also use RAID5 and we have a much more faster read/write
RAID speed is mostly depend on the controller, if you have a cheap hardware card it may be slower than the software RAID.
as i see you have many disk in the array, you should leave one disc for the spare drive at least.

and one more thing, if you use a hardware card it will be resync your array while you can already use the system, but in the meantime the disc r/w speed is much more slower. once the resync will be finish your array speed will raising.
12X2 TB disc will be resync for a while

[micromaster]

I have a HP P410 Raid Card, what do you think?

[phoenix]

I have a HP P410 Raid Card, what do you think?

You should not be using RAID5 with a large (I'm assuming that's what you have) or a system with more than 100 users: Performance Tuning Guidelines for Large Deployments - Zimbra :: Wiki - read that article for details (and search the forums for some further advice).

[vadonka]

RAID5 can easily handle a massive IO workload. Im using RAID5 all of our servers, with vmware and many many virtual machines, including zimbra, and never had any IO problem.

micromaster: you have the latest HP firmware upgrade?
HP released a new firmware DVD in october, i strongly suggest that upgrade your firmware and install the HP drivers bulk pack to your system.

i just tested our server speed (DL180) last night, 10x600GB SAS hdd in two RAID5 array
read: 300-400MB/sec
write: 200-250MB/sec

[nooto]

Hi !

i just tested our server speed (DL180) last night, 10x600GB SAS hdd in two RAID5 array
read: 300-400MB/sec
write: 200-250MB/sec

1. How did you test it by the way ? With Hdparm ? Bonnie++? iozone?
2. What Filesystem do you use ?
3. Do you use LVM ?

And I haven't quite understood if the original question is related to Zimbra server or some kind of File server :}.

N.

[vadonka]

1. hdparm -Tt /dev/sda
2. in esxi 5: VMFS-5, in ubuntu: ext4
3. no

[phoenix]

RAID5 can easily handle a massive IO workload.

Nobody said it couldn't but it doesn't offer the best performance and it certainly does not offer the best security of your data - your data, your servers, your choice.

[nooto]

1. hdparm -Tt /dev/sda
2. in esxi 5: VMFS-5, in ubuntu: ext4
3. no

Your reads seems to be ok, but writes over 200 MB/s ?? This seams questionable, off course it depends on the block size you use. And you do not get the "write" speed using the command:

hdparm -Tt /dev/sda

As it shows only read data. At least I thought so.. In my case with a similar server I could double my writes after changing From raid5 to raid 10 using four SAS disks 10k rpm. This doubling is from 50 to 100 MB/s (write). As for read the numbers are similar.

And for the initial Question: Maybe you are testing your server under high load ??? This could be the case I guess .. and use proper testing software as Bonnie++ or iozone. When your server is not under high load.

I am serving about 30,000 Downloads per day from this server, about 15TB per day.

And the numbers does not add up :> ... 15TB is 15000000 MB so you need read: 15000000÷3600÷24 = 173.611111111 MB/s. So if you serve such traffic then your tests are showing incorrect results. You should google for perf tests with 7.2 disks and raid 5...

[vadonka]

sorry, you're right, im using the 'dd' command for the write test

200MB/sec write speed can achieve with a fast SAS 7200rpm hdd and good hw controller. this speed is internal write speed not over the network.

i can write to my samba server with 120-150MB/sec over the gigabit network.

root@zimbra:/opt/zimbra/conf# dd if=/dev/zero of=/tmp/test.img bs=102400 count=1000
1000+0 beolvasott rekord
1000+0 kiírt rekord
102400000 bájt (102 MB) másolva, 0,519662 mp, 197 MB/s