SMB Reduced Throughput on NAS

[southerndoc]

Since upgrading to macOS 13.0, I'm having SMB throughput issues with my Synology RS1221+ in RAID10 connected over a 10G network.

My throughput routinely slows to around 70-75 MB/sec after an unknown amount of time. If I dismount the NAS and remount it, I can get 790-800 MB/sec upstream and 1000-1050 MB/sec downstream for at least 24 hours.

I have Time Machine connected to the same NAS using AFP. Disabling it doesn't prolong the time before throughput drops.

Has anyone else experienced this, and if so, have you found a setting that keeps it from occurring?

 

[southerndoc]

I just found that this issue occurs when I restart my computer. I have my NAS SMB mounted drive as a login item. For some reason when it boots up, it has max throughput of 70-75 MB/sec until I dismount and remount it.

 

[newadventure]

I see this too. Restarting networking services on the nas will fix it. No need to unmount and remount.

/etc/rc.network restart

Or even just setting the MTU value (which restarts networking services) /usr/syno/sbin/synonet --set_mtu eth4 9000

 

[southerndoc]

Why is it reducing throughput when mounted at login anyhow?