Download speeds drops after a minute (high speed internet)

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putty10
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Download speeds drops after a minute (high speed internet)

Post by putty10 »

Hello,

I've been facing download speeds issues after moving to a new home and getting another provider. The download speeds starts just fine, but drops after 1 minute or so to around 50% of the speed. I've a 1Gbit/s line and all the hardware is up te date. I of course have tested the line and done a iPerf / iPerf3 bandwidth test, and all is fine there. I reach almost 950 MBit/s and the speed holds steady after 10min testing.

Then I've been reading all kinds of articles on sabnzbd wiki and this forum as well and I've made the suggested changes on pages like highspeed-downloading wiki. None of it has made any difference though.

I was hoping someone here has find a solution for this problem.

Thank you in advance!
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sander
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Re: Download speeds drops after a minute (high speed internet)

Post by sander »

The standard approach:

While is NOT dowloading:

In SABnzbd's upper right corner, click on the wrench symbol ("Status and interface options"), then click on first tab Status, and there click on the Refresh Arrow. Post the values of the lower part here, CPU pystone and disk speed.

In the same Wrench pop-up window, then click on Test Download 1GB. Things to measure afterwards:

* mean download speed (in History)
* again in Wrench (only since SAB 3.6.1): Do you see "Download speed limited by"? If so, what does it say?

On my Celeron:

System performance (Pystone) 81735 Intel(R) Celeron(R) J4105 CPU
Downloaded in 25 seconds at an average of 41.3 MB/s
Download speed limited by Disk speed (13x)

So my Disk is a bottleneck in my download speed.
putty10
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Re: Download speeds drops after a minute (high speed internet)

Post by putty10 »

Hi, thank you here are my readings:

Image
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sander
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Re: Download speeds drops after a minute (high speed internet)

Post by sander »

SAB tells the cause: "Download speed limited by ... Disk speed (30x)". The 30x means the disk was 30 times the bottleneck.

And indeed your disk is slow: 30 MB/s. Probably not a SSD?

So ... solve that.
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OneCD
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Re: Download speeds drops after a minute (high speed internet)

Post by OneCD »

Hi @sander, I'm running SABnzbd 3.6.1 on Debian 11.5 with Python 3.9.2 and I don't see a "Download speed limited by" entry. Is there something I need to-do to enable this? I've conducted the tests exactly as shown above.
Stuff I like: Apache bash cron DD-WRT Debian DNSMasq Entware FireFox GitHub ImageMagick Kate KDE LibreELEC Netrunner NFS NVIDIA OpenVPN Orvibo-S20 pfSense Python Raspberry-Pi RAID SABnzbd Transmission Usenet VirtualBox Watcher3 XFCE
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sander
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Re: Download speeds drops after a minute (high speed internet)

Post by sander »

OneCD wrote: September 18th, 2022, 4:41 pm Hi @sander, I'm running SABnzbd 3.6.1 on Debian 11.5 with Python 3.9.2 and I don't see a "Download speed limited by" entry. Is there something I need to-do to enable this? I've conducted the tests exactly as shown above.
That means nor your disk nor your CPU is the bottleneck, but your Internet speed.

Or, more positively stated: your disk and CPU can handle all stuff coming in from Internet.

(Assuming the CPU is fast enough to measure the bottleneck)
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OneCD
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Re: Download speeds drops after a minute (high speed internet)

Post by OneCD »

Ah, that makes sense: my Internet speed is most-definitely the bottleneck.

Cheers! ;D
Stuff I like: Apache bash cron DD-WRT Debian DNSMasq Entware FireFox GitHub ImageMagick Kate KDE LibreELEC Netrunner NFS NVIDIA OpenVPN Orvibo-S20 pfSense Python Raspberry-Pi RAID SABnzbd Transmission Usenet VirtualBox Watcher3 XFCE
putty10
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Re: Download speeds drops after a minute (high speed internet)

Post by putty10 »

sander wrote: September 18th, 2022, 1:35 pm SAB tells the cause: "Download speed limited by ... Disk speed (30x)". The 30x means the disk was 30 times the bottleneck.

And indeed your disk is slow: 30 MB/s. Probably not a SSD?

So ... solve that.
Appreciate it!
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