RAID 0 and 4hdd's - Slow performance

[Dariusz]

Hello

So just to make it clear this was my first time when I made Raid... So I'm not sure if thats normal or not... anyway.

I got 4x WD Re 2 (if I'm not wrong) In raid 0 using LSI Software (motherboard one) 64 kb size.

The problem is when I copy file It start at 100¬ mb and go down to ...30/10... which is just ridicules since single HDD can give me up to 50 mb copy transfer rate...


I run it on Asus Z8PE-D18

So could any1 help me out with it ?

Thanx for help and bye !


Ps forgot system specs. I run Win 7 x64 Professional version however I cant install raid drivers nor chip since asus dont put any avaible drivers for win 7x64 for z8pe d18 yet...

 

[sminlal]

If you're copying a file from one place to another place on the same RAID volume then you're going to be making the heads move back and forth an awful lot - that's called "thrashing". Please believe me when I say that for this kind of activity you're seeing a lot better throughput at 10-30MB/sec than someone with a single drive would see.

 

[MRFS]

Try turning NCQ OFF.

Be sure that 32-bit transfers are ENABLED.

Look also at the "write-through cache" option.

Yes, if you are reading from and writing to the same RAID 0,
you will cause armature thrashing, which will reduce
throughput significantly.


MRFS

 

[Dariusz]

Heya

Thanx for replies!. huh I'm not sure if I understand what you mean or you me.. I got 2 TB RAID 0(lsi) and 3 partitions made in windows. I copy From C to D some data and the trasnfer start at 100-150 and go down to 20-30 :/

About Write-through cache I think I disabled it coz it endanger my data... So I decided to be alil bit more save... I dont think that this could speed down my Raid0 for that much...

Where can I enable 32bit trasnfers ? can I do it once I instaled windows etc etc or will it erase all my data... ?

I got second pc standing next to this one and there if i copy from HDD to HDD i got 40-60 MB if on HDD from partition C to D I usualy get around 30...

 

[chunkymonster]

I run Win 7 x64 Professional version however I cant install raid drivers nor chip since asus dont put any avaible drivers for win 7x64 for z8pe d18 yet...

Not having the proper drivers available in of itself will a cause for poor RAID performance. How do you expect the OS to know how to run the software RAID controller to spec if there is no driver to tell it what that spec is?!

As a comparison, I'm running 4-80GB WD in RAID0 on a Highpoint 2310 and consistently get average reads of 70MB/s, burst speeds of 250MB/s, and sequential reads of 85MB/s...not the best but not the worst...

 

[Dariusz]

Aaaa dont kill mi plz.... Asus didnt provide any drivers for Win 7 x64 for z8pe d18 I will be calling them on monday to see what are my options ... :S Duno if I can instll Vista drivers for chipset and Raid config...

Or can I install them ?

 

[chunkymonster]

Aaaa dont kill mi plz.... Asus didnt provide any drivers for Win 7 x64 for z8pe d18 I will be calling them on monday to see what are my options ... :S Duno if I can instll Vista drivers for chipset and Raid config...

Given that the mobo is a server mobo they might have better drivers for Vista or Server 2003 or 2008, especially since Win7 is a desktop OS and not a server OS.

 

[Dariusz]

Given that the mobo is a server mobo they might have better drivers for Vista or Server 2003 or 2008, especially since Win7 is a desktop OS and not a server OS.

Um true but does it mean that its save to install Vista x64 drivers on Win 7 x64 or just that I'm dumn with my os?

 

[sminlal]

I got 2 TB RAID 0(lsi) and 3 partitions made in windows. I copy From C to D some data and the trasnfer start at 100-150 and go down to 20-30 :/

If the partitions are on the same disk volume (ie, if they all show up within the same "Disk" when you view them under Disk Management), then it doesn't matter if the "drive letters" are different and it doesn't matter if you're using RAID - the files are still being physically copied from one place on the same set of disks to another place on them. That causes thrashing and hurts performance, no matter what drivers you're using.

For sequential copy performance, you'd be better off ditching the RAID configuration and simply setting your drives up as two individual, non-RAID disks with one partition per physical drive. If you did that, copies between the "C:" partition on one physical drive and the "D:" partition on a separate physical drive would be much faster.

But trying to optimize the system for sequential copies is may not be the best way to do things if that's not what you usually use your system for.

 

[Dariusz]

Heya

Thanx sminal ! Ill think about it. So I gees I wont have fast copy files.... btw does Trashing damage my drivers? And is it related only to copying ? or if I will unrar things that would cause trashing too ?

I'm doing mostly graphics so I'm working on files from 5-200 MB size that I need quickly to save/open for my 3D work and for 2D work my files start from 100 mb and end on 5gb+. Would the Raid 0 I got now actually do any good for me or no ?

Thanx again all for ur help !

 

[sminlal]

It's "tHrashing", not "trashing" - and not, it won't hurt your drives or drivers (other than being slow while it occurs).

When you open and save files, you're usually only accessing ONE file on the disk as it's copied to or from memory. RAID 0 is good at that, and you should get good performance.

But if the file is too large to fit into RAM, and if as a result the software is using a scratch file or the system is paging memory to the pagefile, then you might still get thrashing. In that case you'd be better off putting the data files on one physical disk and the page/scratch files on another.

 

[Dariusz]

Heya

Thanx very much for ur help ! Now I know that this Raid system is not complete waste of time About scratch file... well I hope I wont have to use it with 24 gb of ram

Thanx again all for ur time and help ! Bye and have a nice sunday