Speed copying between raids in same machine.

[Guest]

Hi ,

I got a ( I guess ) simple question for storage guru's.

I have two raids mounted in a PC with an Intel i7, ASUS Workstation motherboard.

One raid is a hardware one, done with a SATA raid controller ( 4 disks ) about 350-400 MB/s read and write perfomance. Measured with a software to evaluate perfomance for HD capture. Is a High Point Technology 4322 SATA/SAS RAID.

Second raid is done by software, 3 disks ( raid-0 again ) , about 250-300 MB/s.

Both works fine. OS is XP32. But If I try to copy from/to any raid to the other, or from-to any SATA disk to any SATA RAID, perfomance drops to 60-80 MB/s. So, yes I could record from a HD capture board, but If I want to copy move the data,

Any idea ?.

Thanks a lot,
beloved patriot.

 

[sminlal]

Are you saying that you're getting 60-80MByte/sec for a file copy between RAID volumes at the same time you're doing an HD video capture to one of the RAID volumes?

That doesn't seem unreasonable to me, because it implies that drives in the RAID volume you're capturing to are having to thrash their heads back and forth between the capture file and the file being copied. If you tried to do that with a single hard drive you're performance would probably be well below 10MB/sec.

 

[Guest]

Not at the same time. I tested and capture HD uncompressed, so they're ( both raids) able to maintain at least close to 200Mbytes/sec. But when copying no other task active.

So between both RAID I should achieve something about 200 Mbytes/sec ( at least )... No way... just 60 to 80 mb/s

Thanks,
beloved patriot.

 

[sminlal]

Nothing seems obvious to me. If I were in that position I'd bring up Performance Monitor and try to determine where the bottleneck was - whether the input disk, the output disk, or the CPU was 100% busy (it's not likely to be the CPU but better not to rule anything out).

 

[Guest]

Nothing seems obvious to me. If I were in that position I'd bring up Performance Monitor and try to determine where the bottleneck was - whether the input disk, the output disk, or the CPU was 100% busy (it's not likely to be the CPU but better not to rule anything out).

 

[sub mesa]

How did you connect your disks? To the onboard chipset-powered SATA ports and the Highpoint is PCI-e?

Using Windows XP would mean your stripes are not aligned with the filesystem, but that would affect random I/O not sequential I/O.

 

[sportsfanboy]

Is it possible that the power supply is having a hard time powering 7 harddrives at the same time?

List system specs

 

[sub mesa]

Nah, that would mean the system wouldn't even power on as when the power goes on the disks consume ~30W peak power to spin up; tripping any power supply if it goes over the limit. After that initial spinup the usage is about 6-10W but not higher.

 

[Guest]

This prob is getting me crazy...

I made some tests with a Mac clone, with OSX 10.5.8. And what happens ??


If the destination disk or raid subsystem is formated with NTFS performance keeps as windows ratios ( 60 to 80 MB/s ). if I reformat the destination RAID system ( originally NTFS ) to HFS .. Then I got 220 Mb/s !!!. ( Reading from a RAID-0 two SATA disks ).

What it does mean ?, is then a Windows issue ?, is then a drivers issue ?, is a disk format issue (low perf on NTFS) ?.



Thanks,
beloved patriot.

 

[sub mesa]

Using NTFS on Mac OSX would probably lead to lower performance, as it probably uses the NTFS-3g open source driver; and while its getting better, i can imagine performance isn't their greatest goal right now; they are not even feature complete.

 

[Guest]

System Specs : ( I move the external case with drivers between both computers )

Computer 1 :

ASUS MB P6T Workstation Revolution, 6 PCI-E 16x., I7 920.
XP 64/32, SP2
6 Gb DDR3, 1333
HighPoint RocketRaid 4322 ( 2 Mini - SAS )
Stardom External Case , 2 Mini-SAS, 1 RAID-0 with two 1tb S-ATA , 1 RAID-5 with three 1 Tb S-ATA, 2 free (non raid ) 1.5 Tb S-ATA


Computer 2 :

ASUS P5K, Core2Quad 6600
OSX 10.5.7
4 Gb DDR2
HighPoint RocketRaid 4322 ( 2 Mini - SAS )
Stardom External Case , 2 Mini-SAS, 1 RAID-0 with two 1tb S-ATA , 1 RAID-5 with three 1 Tb S-ATA, 2 free (non raid ) 1.5 Tb S-ATA

 

[Guest]

Using NTFS on Mac OSX would probably lead to lower performance, as it probably uses the NTFS-3g open source driver; and while its getting better, i can imagine performance isn't their greatest goal right now; they are not even feature complete.

I agree, writing on NTFS on a OSX could be slower..., about 60MB/s. But is the same speed ( a bit lower) than I got with Windows XP64 !!.

So the difference couldn't be so big, XP64 : 60-80 Mb/s and OSX : 220 Mb/s. Same disks, same raid controller, but different format ? ( even I'm reading NTFS in Mac)... what the hell is happening here

 

[sub mesa]

Try increasing the cluster size when you create the NTFS filesystem. That would wipe all data from your volume though, so only do this if you have a backup of course.

It may yield higher throughput on XP.

 

[sminlal]

Are you testing this by copying a single file, or are you copying multiple files? Multiple files would slow down the transfer - the more, smaller files you have the more time will be spent finding them on the input disk and creating directory entries and on the output disk.

 

[Guest]

Big files... 8 to 15 gig files.

 

[staats]

Try this.. Try and benchmark both RAIDS at once. There may be another bottle neck. I am running a RAID 5 array with an LSI 8708EM2 card. If I have extreme I/O on other drivers on another controller, it can affect the performance of the RAID 5 array simply by creating I/O bottle necks elsewhere.

Even just using 4 drives in a JBOD configuration with an integrated controller can kill performance. While "breaking in" the last four drives, I connected all four of them to the integrated ICH10 controller. Checking for errors with only one drive running ran at about 100-110MBs. With all four drives simultaneously, it dropped to 50-60MBs per drive. If I ran all four drives while benchmarking the RAID 5 array, all numbers were impacted.

 

[sub mesa]

staats: interesting story, but are you sure it isn't just the PCI bus that you're limited by?

 

[asch75]

I have a similar problem. If I copy a large amount of files form the Highpoint 4320 to the main HDD (SATA motherboard controller), the computer slows down.
Opening Internet explorer and typing is so slow...


My system specs:
ASUS P8B WS
16GB DDR3
Highpoint Rocketraid 4320 on PCIe x16(x8 link)
8x Western Digital 500GB RE2 (5002ABYS) RAID5
1x Western Digital 2TB (Onboard 6gb SATA)