Slow Write Speed

[Adam64]

Hi All,

 

I copied about 230GB to my unRAID last night and it was averaging about 25MB/s write speed (after the initial 100MB/s as the cache filled up).  Searching on this forum made it seem like most people are getting much higher write performance than I am.

 

My hardware is pretty beefy - i7-4770k, z97 chipset, 32GB RAM.  My hard drives attached to the motherboard's SATA controller.  Any thoughts on what I could do to improve the write performance? 

 

Diags attached.

 

Edit: I'd be willing to get a higher performance SATA controller if that would make it significantly better.

unraid-diagnostics-20160129-2320.zip

[Squid]

Are those speeds to the shares (3 of them) that are set to use the cache?  If not, then its actually fairly reasonable to expect speeds like that.

[Adam64]

Are those speeds to the shares (3 of them) that are set to use the cache?  If not, then its actually fairly reasonable to expect speeds like that.

OK,  thanks for the reply.  Is there anything I can do to improve it?  New controller maybe?

 

[Squid]

Are those speeds to the shares (3 of them) that are set to use the cache?  If not, then its actually fairly reasonable to expect speeds like that.

OK,  thanks for the reply.  Is there anything I can do to improve it?  New controller maybe?

To a non-cached share, you're not really going to improve it significantly (http://lime-technology.com/forum/index.php?topic=4339.msg38618#msg38618) (Generally, mb ports are going to be the fastest)

 

To get the huge bump, you're going to have to set the shares to use the cache drive

 

 

[JorgeB]

That seems a little on the low side for your hardware,  would expect more like 40MB/s but don't see anything obvious on your diagnostics.

[JorgeB]

I see you have file integrity plugin installed, if you have it set to automatically hash new files, it can sometimes start hashing a files during the copy, this will slow it down.

 

See example below, copy of the same 2 files with auto hash enable and disable, with auto enable fist file copies at the same speed, but the second will slow down due to the hashing of the first.

[Adam64]

I see you have file integrity plugin installed, if you have it set to automatically hash new files, it can sometimes start hashing a files during the copy, this will slow it down.

 

See example below, copy of the same 2 files with auto hash enable and disable, with auto enable fist file copies at the same speed, but the second will slow down due to the hashing of the first.

 

Great point Johnnie.  Thanks for sharing this.