Array's write speeds go from 250mbs to 30mbs within seconds

[Mexicanfernando]

Array's write speeds go from 250mbs to 30mbs within seconds. I'm transferring a whole server worth of data and it seems like it's going to take over a week because of this problem. It should take like 10 hours.

 

Turbo write is on. Cache is temporarily disabled because it fills up so fast. I know I'm writing straight to the array but all of my drives are rated for 250mbs, even the parity, and i have an NVME drive that can do 7000MBS but it seems no matter what drive I try and write to it goes down to 30.  I'm running a 10G network at well. It's very frustrating. It seems I have everything configured right but my array's write speed is just so low. Can anyone help shed some light on this? 

Edited April 10, 2023 by Mexicanfernando

[trurl]

The initial burst of speed is simply RAM buffering. After that, write speed will be slower than single drive speed due to parity updates. Turbo would often be faster than 30 though. One thing you could do is remove parity until initial data load is done, then build parity after.

 

Attach diagnostics to your NEXT post in this thread and we can check your hardware and configuration.

[Mexicanfernando]

I had thought about removing parity for that reason but it takes over a day to just check it. Maybe it would still be a bit faster though. Here are my diagnostics. Any other ideas or settings to change would be greatly appreciated. 

tower-diagnostics-20230409-2330.zip

[trurl]

SSDs in the parity array cannot be trimmed, and can only be written at parity speed.

 

Why do you have so many pools? And your "prefer" shares have files on each of these pools, but can only be configured to use one of the pools (Fix Common Problems is telling you about this).

 

Another thing that can cause slow writes are lots of small files, since there is some overhead with creating each file.

[Mexicanfernando]

I have 3 pools right now, a gen4 NVME Cache drive, an SSD drive which I intend to remove, and a slower NVME drive which will be a cache appdata backup.

 

Do you think having an appdata backup is unnecessary? Tell me if I'm wrong, the way I understand it some files don't get moved to the array so I was just thinking they should be be backed up someplace. 

 

One other quick question: I have a Gen4 NVME in my array as well to run video editing projects on thinking it would read a lot faster but it seems to be writing at the same speeds as the other HDDs. Do you think that is unnecessary because it will automatically revert to the speed of the slowest drives on the array? 

 

 

 

Edited April 10, 2023 by Mexicanfernando

[trurl]

19 hours ago, Mexicanfernando said:

an appdata backup

Usually this is done on the array.

 

19 hours ago, Mexicanfernando said:

seems to be writing at the same speeds as the other HDDs

 

22 hours ago, trurl said:

SSDs in the parity array cannot be trimmed, and can only be written at parity speed