Issue with Ubuntu and Iozone

[Paco80]

Hello everyone,

I recently assembled a small NAS and I am currently testing the performance with different solutions.

I just tested Ubuntu with mdadm and Samba with Iozone.

The issue happens when Iozone is writing a 2GB file. I get the following error:

Error writing block 26066, fd= 3
write: no such file or directory
iozon: interupted​

It repros pretty much all the time and I don't have any trouble writing 5Gb files the normal way.

Any idea what the problem is?

Thanks.

 

[Paco80]

Sorry, not 4GB but 2GB.

 

[00Roush]

Are you running Iozone locally on the NAS with Ubuntu or are you running it from another machine to test the NAS samba share?

00Roush

 

[Paco80]

I'm running it from a windows 7 machine to test the samba share.

 

[00Roush]

Are you using any security settings on the Samba share? I ask because I am trying to think of things that would interfere or cause problems in your setup. Using just a basic Samba share with no security and no special settings would be the best way to test. Also make sure to disable the windows firewall as it could also be causing your problem. Mdadm is something else that might be causing problems. Have you tried testing with just a single disk?

You know now that I think about it I recall having some sort of problem using Vista and testing with Iozone or large files... can't remember for sure. Either way I fixed it by changing the "size" setting under lanmanserver in the registry. Not sure if it would work in Windows 7 or if it has anything to do with your problem. I outlined the change in my DIY tips thread for Vista as the server. You might try it and see if it helps.

I have not actually tested iozone with windows 7 yet so maybe I will give it a spin and see if I have any problems. Now that I think about it... what version of Ubuntu are you running?

Hope that isn't too much to throw at you. Let me know if any of it helps.

00Roush

 

[Paco80]

Thanks for the reply.

No I am not using any security settings (not that I know off) on the samba share. I used the server version of Ubuntu 10.4. I'll try with a single disk without mdadm. I'll give it another try this week-end.

In the meantime, I started testing with Win2k8 R2 on the NAS (Ubuntu is installed on another drive), I have weird results with Iozone, transfer rate seems a bite high. I'll share the results on another thread.

But I had some issues with my testing on 2k8, I would have some errors saying the file didn't exists. In fact, the files wasn't there when browsing from Windows 7. But when browsing locally from win2k8, the files were still there. I fixed it by disabling the offline mode in Windows 7. It could be the same issue with Ubuntu.

 

[Paco80]

I forgot to mention that I'm testing the raid1 on 2 WD Green EARS (with their new Advanced Format). It is a PAIN to work with, FreeNAS has terrible performance, with or without the jumper. Ubuntu seems ok with the jumper (except for that issue), UnRaid seems ok as well with jumpers. Didn't test without the jumper for Ubuntu and UnRaid.

Windows 2k8 R2 works just fine without jumper. And from what I can tell have pretty good perf.

 

[Paco80]

I ran the test on the disk outside the raid array. Didn't have any trouble.

I might stop my inestigation and just go with Win2k8 R2. It seems to have descent perf and is easier to manage for me.

Thanks a lot for your help.