Overall performance is not acceptable

[aglyons]

I have had my issues with network performance and now I am seeing overall internal performance that I can't ignore or accept.

 

I am transferring files from one share to another share, internally using the Dynamix File Manager. I have 8 drives that are all SATA3 600Gbps. So why is it that this internal file transfer is running at 11MB per second?? That is 2.2% of the drives potential throughput!

 

I understand that UnRaid does not stripe data across drives. But going from one SATA3 drive to another SATA3 drive, internally should NOT be going this slow. I've seen transfers start at a high speed but then peter out to almost nothing dropping as low as 6MB/s

 

The target nor the source share DO NOT use the cache. 

 

I'm starting to feel like UnRaid was not the right option to go with and I should have gone with Trunas instead.

 

[JorgeB]

5 minutes ago, aglyons said:

But going from one SATA3 drive to another SATA3 drive, internally should NOT be going this slow.

Unraid is always pretty slow when transferring data inside the array, because of how parity works, and currently it's not possible to use turbo write for internal transfers, though I would still expect it to be faster than that unless you're using SMR drives, what drive model is parity and the disk you're writing to?

[wgstarks]

Have you tried using cp or rsync for comparison? I was attempting to clear a failed drive yesterday and found rsync to be much faster than using dynamix file manager.

[aglyons]

4 minutes ago, JorgeB said:

Unraid is always pretty slow when transferring data inside the array, because of how parity works, and currently it's not possible to use turbo write for internal transfers, though I would still expect it to be faster than that unless you're using SMR drives, what drive model is parity and the disk you're writing to?

 

@JorgeB - All drives are Seagate Ironwolf, 5x6TB + 3x8TB except parity. Both parity drives are Seagate Exos 12TB and 14TB.

 

 

@wgstarks - I've had a challenge trying to get rsync on UnRaid to appear as a target on my Synology Hyperbackup APP to no avail. I'm not that much of a CLI guy at present so running rsync at the CLI is not something that I readily know how to do.

 

[JorgeB]

8 minutes ago, aglyons said:

All drives are Seagate Ironwolf, 5x6TB + 3x8TB except parity. Both parity drives are Seagate Exos 12TB and 14TB.

I would expect better performance with those, especially since it looks like you're transferring large files, though like mentioned it will never be close to disk speed, maybe 50/60MB/s at best, I believe the plugin uses rsync internally for the transfers, but never tested myself, you could try for example with midnight commander (mc on the console) to compare, but note that it would be much faster transferring to a pool or an unassigned device then transferring back to the array with turbo write enable, I always try to plan things to avoid internal transfers in the array.

 

 

[aglyons]

The transfers speeds are bouncing around topping out at 160MB/s but then dropping down to >30MB/s then back up for a short period but then back down. It never goes much higher than 160MB/s which is still way off the 500MB/s potential of a single drive and more realistically, stays in the lower 30MB/s or less speeds for the majority of the activity.

 

 

[JorgeB]

Just now, aglyons said:

which is still way off the 500MB/s potential

No HDD can write at 500MB/s.

[aglyons]

6 minutes ago, JorgeB said:

No HDD can write at 500MB/s.

 

True, just checked the specs on the Ironwolf drives and they are rated at 240MB/s on paper.

 

I guess my frustration is the constant up and down speeds. Especially dropping down so low for so long. 

 

I know they are different animals but I don't see this kind of fluctuation from the old Synology box I have which doesn't have any highspeed cache at all.

[JorgeB]

Plugin might just not be reporting a correct/stable average, the actual speed is what really matters, at 100MB/s you can transfer around 300GB per hour, if you get anywhere close to that I would consider a great speed for an internal transfer.

[aglyons]

19 minutes ago, JorgeB said:

Plugin might just not be reporting a correct/stable average, the actual speed is what really matters, at 100MB/s you can transfer around 300GB per hour, if you get anywhere close to that I would consider a great speed for an internal transfer.

 

So I did a very non-scientific test and timed a section of files. It transferred 30.9GB of data in 8 minutes. If my math is right, that works out to approx 66MB/s average transfer rate. This is a significant performance hit when considering hardware capabilities IMO.

 

I've read people talk about the purpose of UnRaid and running this kind of server in their operations. Many have described their viewpoint as this is an archive server. Somewhere to put files that are not accessed very often. I didn't come across this sentiment until well after I set all of this up. This may be my downfall as I did not expect this level of performance hit. 

 

I deal with a lot of large media files as I work with video content. I need not only large secure storage but also fast. I upgraded my network to support 10GBe connections between my workstation and the UnRaid server. With this performance hit, it seems like it was a waste of $$ as the network is not the bottleneck.

 

I foresee the comments from that last statement. Secure, Fast, Affordable - Pick two out of the three options.

 

I think I'll have to research TruNas and see how I can port everything over.

[JorgeB]

19 minutes ago, aglyons said:

works out to approx 66MB/s average transfer rate.

Seems about right to me.

1 hour ago, JorgeB said:

maybe 50/60MB/s at best

 

Also as already mentioned Unraid will always be slow for internal transfers, it's because the way parity works, you can find more info here, turbo write part is not relevant since it can't currently be used for internal transfers, which by itself is a shame since it would be faster.

[JorgeB]

Forgot to mention, for speed Unraid has pools, currently only btrfs is supported with raid0/1/10/5/6 profiles, soon ZFS will also be supported.