Download speeds gradually slow down

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SKPN
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Joined: April 16th, 2020, 9:31 am

Download speeds gradually slow down

Post by SKPN »

Hi everyone,

I've been using SAB for a little over a year now, and have been running into this issue quite often. When I download very large files, or even multiple smaller files in succession, my download speeds gradually slow. When the file starts downloading, and for the first 10 minutes or so, it will generally hit anywhere from 40-65MB/s. But after that, speeds continue to drop until they're down under 10 MB/s, and sometimes under 5. If I pause the downloads for a few minutes, then start them back up, the speed goes back to normal.

Is there some kind of setting that limits the bandwidth after a certain time period or after so much data has been transferred? I do not have the same issue with NZBGet; download speeds are maintained until finished there, though I still prefer SAB for everything else.

Any help on this would be greatly appreciated.
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safihre
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Re: Download speeds gradually slow down

Post by safihre »

Most likely SABnzbd just can't keep up fully with the speed. You might also see a high CPU usage of SABnzbd.
In this case since it's only happening after 10 minutes, I would suggest you set a speed limit in Config > General that's a little bit below your maximum,
So for example set it for now to 35MB/s. This way SABnzbd can keep up and the cache is never filled to the maximum.
If that works fine, try 40MB/s for example.
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SKPN
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Joined: April 16th, 2020, 9:31 am

Re: Download speeds gradually slow down

Post by SKPN »

safihre wrote: April 17th, 2020, 8:08 am Most likely SABnzbd just can't keep up fully with the speed. You might also see a high CPU usage of SABnzbd.
In this case since it's only happening after 10 minutes, I would suggest you set a speed limit in Config > General that's a little bit below your maximum,
So for example set it for now to 35MB/s. This way SABnzbd can keep up and the cache is never filled to the maximum.
If that works fine, try 40MB/s for example.
I actually have a gigabit connection, so even when it hits 65MB/s, it's only hitting just over half of my actual connection speed. CPU usage tops out at ~9% at top speed, and I have my cache limit set at 4GB. I can try lowering the max connection speed to 80 (currently it's at 125 even though it never comes close to that) and see what happens. I appreciate the help!
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safihre
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Re: Download speeds gradually slow down

Post by safihre »

Maybe give NZBGet a go, it might get higher speeds on your system.
If you like our support, check our special newsserver deal or donate at: https://sabnzbd.org/donate
SKPN
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Posts: 3
Joined: April 16th, 2020, 9:31 am

Re: Download speeds gradually slow down

Post by SKPN »

safihre wrote: April 19th, 2020, 10:28 am Maybe give NZBGet a go, it might get higher speeds on your system.
I tried NZBGet, and I don't have any issues with slowdown there (although I still only max out around 65MB/s), but I like SAB better overall. The built in unzipping for the watch folder and overall interface is better IMO.
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