I've been using UnRaid for nearly a year now and have been generally happy, however as our family usage has increased I've come across an issue and I don't know if it's my setup, or just the way things work.

 

Basically it comes down to the fact that if more than one person tries to watch a video from a single disk, both experiences become unwatchable (stuttery, loses sync, etc). I've found that coping to UnRaid while someone is watching a video can cause it to crap out too.

 

I understand that a single disk only has so many IOPS available, and that there is a limit to what a disk can do (especially pushing out 1080p movies which all my movie files are).

 

Is this normal? Is this the behavior I should expect? Are there any suggestions to ease the impact so that two users can view a movie from the same disk?

 

I am trying to understand if this is a limitation of the UnRaid non-RAID single disk solution, or is there possibly something else happening.

 

Thanks

Bill

 

It's something else. A HD movie is in the 5Mbps to 10Mbps range and a HDD should be able to serve multiple streams at that speed easily.

Just to clarify, you are saying that the disk (which is a WD Green disk BTW) should be able to serve up multiple 1080p sessions without issue, and that it should only take 5-10Mbps of bandwidth, so I should be able to push out multiple streams across the network (which is Gigabit)?

 

Do you have any suggestions on how this might be troubleshot?

Are the drives set to AHCI? What are the hardware specs? Which SATA adaptors? Post a syslog.

What sort of speeds do you get from a parity check?  You should probably be getting something in the range of 80MB/sec.

 

Stephen

I have attached my syslog for review, however I had to power off over the weekend, so it's only 3 days of logs if that matters.

 

I am pretty sure the drives are set to AHCI, but I will confirm tonight.

 

As for system specs:

AMD Athlon II X2 260 Processor

4GB Ram

ASUS M4A88TD-V Motherboard

Intel 10/100/1000 NIC

4 Hard Drives:

1x WD2002FAEX 2TB Parity (WD Black)

3x WD20EARX 2TB Drives (WD Green)

All are on motherboard SATA connectors (3GB SATA I think)

 

I am running a Parity Check now, and getting around 55,000-60,00 KB/sec (so 55-60MB/sec, right?)

syslog-2012-03-27.txt

I have confirmed the drives are in AHCI mode (I am building another UnRaid server and they won't even show in IDE mode, so I guess this wasn't an option).

 

Any other suggestions?