Poor file transfer rates all of a sudden?

[MrGrumpie]

Hi all

 

After transferring over 10TB worth of data to my array and getting on average 30MB/second writing directly to a disk, and up to 60MB/second writing to the cache disk, I've recently come across a frustrating problem.  I've just rebooted the server now, and doing a small file transfer to one disk is only giving me maximum 5MB/second

 

It's been like this for a few days, with the average being 3MB/second.  Nothing has changed, but the transfer rates are really sucky.  Anyone come across this before?

 

My network is Gigabit wired over Cat5.

 

Thanks

[bkasten]

Hi all

 

After transferring over 10TB worth of data to my array and getting on average 30MB/second writing directly to a disk, and up to 60MB/second writing to the cache disk, I've recently come across a frustrating problem.  I've just rebooted the server now, and doing a small file transfer to one disk is only giving me maximum 5MB/second

 

It's been like this for a few days, with the average being 3MB/second.  Nothing has changed, but the transfer rates are really sucky.  Anyone come across this before?

 

My network is Gigabit wired over Cat5.

 

Thanks

 

It could be many things, however, where I would start if I were you is the network. You did not indicate any changes you made to unRAID, or your workstation, so assuming that nothing has changed on either of those ends, check the middle.

 

Consumer grade network equipment is notoriously bad, and  short lived. Are there any switches between your workstation and unRAID? Try taking them out and test the speed. Is your router still functioning correctly? Can you try copying to other computers on your network? How is the wiring/cabling? Are any of the ends pulled or frayed? Do they click in all the way, and stay there?

 

Over time I have had several routers fail, and many switches too. Sometimes they have failed completely, but other times they have failed almost in-perceptively at first, getting progressively worse until performance was really bad.

 

If you can eliminate any obvious failures on your unRAID, failed disks namely, and your workstation is working up to par, I would look at the middle, the network.

 

For me this would be the starting point. If you can determine that all your network equipment is working, and not the cause, then I would move on from there.

 

Bruce

[MrGrumpie]

I ran a quick telnet session and the server shows connection at 1gb (I've got a network switch between this and the router).  Strangely enough, I just did another transfer and it maxed at 30MB/s and another one 30 mins later which stuck at 5MB/s???

[bkasten]

Hmmm, intermittent issue. Nice, those can be the worse.

 

My first thought is patch cable. Are they all fully seated? Are they all in good condition? No kinks, bends or bad ends? Are they "loose" in the plugs?

 

Those are my first thoughts.

 

Generally, switches and routers are consistent when they fail, bad all the time. Cables on the other hand...

 

Can you swap some out, one at a time and test?

 

Anyone else have ideas?

 

Bruce

[MrGrumpie]

I think you may be right re: the cables.  Thinking about it, since I did the initial transfer I have relocated the server so it's using a different patch cable.  Time for some testing in that area methinks...

 

Thanks for your help