Poor RAID 5 read performance

[filmcomposermark]

I'm getting poor read performance (50 MB/s to 90 MB/s seq) according to HD Tune, CrystalMark and AS SSD Benchmark.

I'm using 3 x 1 TB WD Black Drives in RAID 5 configuration in the StarTech S354UFER E-Sata enclosure. The e-sata is JMicron I believe. The motherboard ASUS P8P67 .

Any idea where the problem might be?

 

[i7Baby]

What version eSATA?

 

[HEXiT]

thats typical for them drives. although they can occasionally (reading the rite size files and how full the disk is) get up to 110MBps, but 50-90MBps is typically the area they run at.

http://hdd.userbenchmark.com/Compare/WD-VelociRaptor-1TB-vs-WD-Black-1TB-2010/1389vs1580

http://en.wikipedia.org/wiki/Standard_RAID_levels

raid 5 is for security not speed so you wont get any speed increase like you would with raid 0.
raid zero with the drives would get you maybe 140MBps to 160MBps. still not great but fast enough for most peoples needs.
my raid 0 has been very stable since day 1 its been running 4 years now with no issues (2x1tb spinpoint f3's). so if fear of lost data is the reason you went with 5 instead of 0 then i would say give raid 0 a go.

 

[filmcomposermark]

What version eSATA?

3GB - using JMicron SATA Controller JMB362

The thing is I'm getting 117 mb/s from my single OS hard drive inside the computer from the same benchmark utility. Admittedly it's on a 6G SATA port - but even so.

 

[filmcomposermark]

thats typical for them drives. although they can occasionally (reading the rite size files and how full the disk is) get up to 110MBps, but 50-90MBps is typically the area they run at.

http://hdd.userbenchmark.com/Compare/WD-VelociRaptor-1TB-vs-WD-Black-1TB-2010/1389vs1580

http://en.wikipedia.org/wiki/Standard_RAID_levels

raid 5 is for security not speed so you wont get any speed increase like you would with raid 0.
raid zero with the drives would get you maybe 140MBps to 160MBps. still not great but fast enough for most peoples needs.
my raid 0 has been very stable since day 1 its been running 4 years now with no issues (2x1tb spinpoint f3's). so if fear of lost data is the reason you went with 5 instead of 0 then i would say give raid 0 a go.

I didn't realize the Blacks were so awful. But I'm particularly shocked that my single HD inside the computer are outperforming a RAID even if 5 isn't quite as fast to read as 0.

Thanks for the links btw.

 

[HEXiT]

the drive inside your pc doesnt have to mirror its data so should be faster but not by a huge amount. maybe your raid is fragmented heavily and causing excessive slowdown or is getting near full. also note for every partition a hdd will loose about 10% in raw speed. so if your raid has 2-3 partitions you could be loosing as much as 20%-30% just for splitting the drive into smaller sections.