Slow read speeds?

[Dub]

I'm having an odd issue since jumping to 6.12 where I can write to a share relatively quickly, but it seems the read speed is considerably slower than in the past. I've played with SMB tweaks and SMB parallel and that doesn't seem to do much of anything. I haven't changed anything hardware wise or with the network infrastructure.

Following a couple other threads, I went ahead and did a couple iperf3 single stream tests...

Client (2.5gb) -> Server (10gb)

 

That seems perfectly fine.

 

Server -> Client

 

Wha?

 

You can see this mirrored in basic file copies. If I read a file that was just written to the cache -- it is surprisingly slow: 

 

 

 

Copying a file from the array is about the same speed.

 

 

But the weird thing is, if I copy a file from a mapped SMB share that is on the cache to a DIFFERENT share that is on the array, I get this:

 

 

What the heck? Shouldn't the separate shares make it read as if they were disparate drives? How can I read from the array at 1.1gb copying across the network, but I can only download the exact same file at 60mb? Why does copying between shares suddenly fix the read speed issue?

 

Just to be sure it wasn't some strange local SSD issue, I copied the files to a separate SSD/controller but I get the same issues:

 

 

I am baffled. Help me Obi-Wan, you're my only hope.

 

Attached are my diagnostics too:

tower-diagnostics-20240404-0338.zip

 

[itimpi]

The last few 'fast' copies will be because the copy is not actually going across the network as you think but is running locally within the server as Windows has triggered server side copying.

 

The iperf results suggest you have a networking issue in one direction.   What the cause is I do not know, but that is what you need to be concentrating on solving.

 

[Dub]

On 4/4/2024 at 4:11 AM, itimpi said:

The iperf results suggest you have a networking issue in one direction.   What the cause is I do not know, but that is what you need to be concentrating on solving.

 

Thank you! I'm really baffled why it's only an issue one direction, but I'll take a peek!