Download speed drops to KB/s

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saintnick
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Download speed drops to KB/s

Post by saintnick » May 11th, 2018, 10:40 am

Since recently some Synology NAS users including myself are noticing that Safihre Sabnzbd 2.3.3-34 download speed will be fine for a few minutes at full MB/s and then drop drastically and stay at just some KB/s.

There's a thread (in Dutch) over at synology forum. (not allowed to paste link :-(

Speedtests with either Domotz or wget show full download speeds, for me at 13.7MB/s on my 100mb/s glass fibre connection. Also speed tests from a different device to the same usenet provider for the same content also show full speed. So it has be a local bottleneck on the NAS.

How do we find the bottleneck?

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safihre
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Re: Download speed drops to KB/s

Post by safihre » May 12th, 2018, 3:12 am

Your NAS is too slow to handle SABnzbd at full speed, so it starts to use swap after a while.
Try setting Article Cache to about half of the memory in your NAS.
Then try setting the speedlimit lower. Downloading from usenet is much more CPU intense then simple wget.
For example try setting it at 5MB/s to start and see how long it stays fine like that.

saintnick
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Re: Download speed drops to KB/s

Post by saintnick » May 12th, 2018, 8:29 am

Thanks, I'll try that. But as I wrote, for a couple of years and until recently (I suspect the update) Sabnzbd would always give me full 100mb/s speed without issues. So something has changed, and I'm not the only one...

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safihre
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Re: Download speed drops to KB/s

Post by safihre » May 14th, 2018, 2:54 am

Could you (and others) maybe try this modified version of 2.3.3 spk-file?
https://github.com/Safihre/spksrc/relea ... bd-oldyenc (building more archs right now)
(see arch naming convention here: https://github.com/SynoCommunity/spksrc ... logy-model)

I want to identify if the problem is in the C-code or the Python code.
Thanks!

morgan1993
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Re: Download speed drops to KB/s

Post by morgan1993 » May 18th, 2018, 1:33 am

How come it affects the download speed?

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safihre
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Re: Download speed drops to KB/s

Post by safihre » May 18th, 2018, 9:51 am

I won't know untill I get test results..

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