Download slows down while unpacking

[darthbane]

Hi,

I use sabnzbd on a LXC in proxmox. I noticed that the download drops to almosst zero, then to zero when an unpack starts. I thought maybe it was too much for the HDD so I put the incomplete temp folder to an mount on a SSD, but it is the same behavior. When the unpack finishes, the download resumes with normal speed and sabnzbd becomes responsive again. There is NO high CPU usage for the container, so there must something going wrong, badly..
Does anyone have an idea?

I stress tested the system + the LXC with "stress" from stress-ng package. It works as expected with high load. So I guess it must be a prolme with sabnzbd/unrar integrations.

best greetings

[shypike]

Please check Settings->Switches item "Pause Downloading During Post-Processing".
Not sure if that is the cause, but it's worth checking.

[darthbane]

thanks for the reply. It is unchecked. The download goes down slowly and sabnzd is getting very laggy. I noticed that my container starts using swap, even there is plenty of RAM available. But the slowdown happens even when no swap is used, don't know if this is linked.

[safihre]

You should enable that option.
Clearly your disks cannot keep up.
Make sure Direct Unpack is disabled.
Swap is being used because your disks aren't able to wrote the stuff fast enough.