Slow downloads - temporarily fixed by Windows reboot

[guitarboy]

I'm typically seeing download speeds of 10-12 MB/s. I have a wired gigabit internet connection, running Windows 10. and expect to get downloads at least 4-5x faster. I occasionally do see downloads in the 50-60 MB/s range, but those are the exception.

Here are the stats from the SABnzbd status screen:

System performance (Pystone) 63938 Intel(R) Core(TM) i7-4510U CPU @ 2.00GHz AVX2
Download folder speed 288.5 MB/s C:\Downloads\incomplete
Complete folder speed 298.6 MB/s C:\Downloads\complete
Internet Bandwidth 50.5 MB/s 404 Mbps

Consistent with this, the Ookla Speedtest app measures my download speed around 400 Mbps.

Here are the results from the 1GB test download - slightly faster in this case (13.7 MB/s) but still not the speed I expect:

Nametest_download_1000MB
Completeda few seconds ago
StatusCompleted
Size1.0 GB
CategoryDefault
PathC:\Downloads\complete\test_download_1000MB
Sourcehttps://sabnzbd.org/tests/test_download_1000MB.nzb
DownloadDownloaded in 1 min 17 seconds at an average of 13.7 MB/s
Age: 49d
Serversnews.astraweb.com=1.0 GB
Repair[sometestfile-1GB] Quick Check OK
Unpack[sometestfile-1GB] Unpacked 2 files/folders in 3 seconds

[/quote]

My primary server is Astraweb with an unlimited account. I use a NewsDemon block account with unlimited speed as a backup. I've tried swapping the two servers in priority but with no difference in performance. I've also tried with and without VPN without seeing a difference.

I have noticed that I'll temporarily get faster speeds immediately after I reboot Windows, but within a day I'm back to the slower downloads.

I've read other posts about download speed but don't understand why I'm not getting better performance. Hoping the information I've provided can be used to point me to a solution.

[sander]

The usual items:

* 12MB/s sounds like fast ethernet. What speed do you get with the 1GB or 10GB download on https://speed.hetzner.de/ ?
* how many connections to your newsserver? Rule of thumb: start at 5 connections, measure speed, and increase number of connections in steps of 5 until the speed does not go up anymore
* "System performance (Pystone) 63938 Intel(R) Core(TM) i7-4510U CPU" ... 64.000 ? That's slower than my Celeron CPU. My Celeron achieves 50 MB/s. Oh, your i7 is 4th generation, from 2014, so a bit ageing. Still: I would expect something better than 64.000.

[guitarboy]

* 12MB/s sounds like fast ethernet. What speed do you get with the 1GB or 10GB download on https://speed.hetzner.de/ ?

I'm getting around 20 MB/s on the 10GB file, 25 MB/s on the 1GB file.

* how many connections to your newsserver? Rule of thumb: start at 5 connections, measure speed, and increase number of connections in steps of 5 until the speed does not go up anymore

I played around with connections to Astraweb. I seem to get higher speeds with more connections. Currently set at 50 connections, the maximum allowed.

* "System performance (Pystone) 63938 Intel(R) Core(TM) i7-4510U CPU" ... 64.000 ? That's slower than my Celeron CPU. My Celeron achieves 50 MB/s. Oh, your i7 is 4th generation, from 2014, so a bit ageing. Still: I would expect something better than 64.000.

I tested a newer computer on the same network. Pystone was 285000 and speeds were much faster, so my older computer is definitely a limiting factor. But as you say, I still think I should be getting faster downloads, and sometimes I do. Today the test downloads are closer to 20 MB/s.

Why should the Windows reboot make a difference?

[guitarboy]

Why should the Windows reboot make a difference?

After reboot:

Nametest_download_10GB
Completeda few seconds ago
StatusUnpacking: 08/11 - 0:31 left
Size10.3 GB
CategoryDefault
PathC:\Downloads\incomplete\test_download_10GB
Sourcehttps://sabnzbd.org/tests/test_download_10GB.nzb
DownloadDownloaded in 2 mins 27 seconds at an average of 71.6 MB/s
Age: 50d
Serversnews.astraweb.com=10.3 GB
Repair[sometestfile-10GB] Quick Check OK

[sander]

Why should the Windows reboot make a difference?

I have no idea. I personally don't use Windows. And probably not a SABnzbd problem then.

EDIT: after a reboot of Windows, what is the pystone performance reported by SABnzbd? If that is high after a restart, then I'm guessing some process is junk your CPU power.

[safihre]

Are you using SABnzbd 3.6.1?
In the Status and Interface settings window, after a slow download, does it show anything about source of slowdown? We have a basic detection mechanism for that now built in.
If nothing extra is shown, it couldn't detect it.

[guitarboy]

Are you using SABnzbd 3.6.1?
In the Status and Interface settings window, after a slow download, does it show anything about source of slowdown? We have a basic detection mechanism for that now built in.
If nothing extra is shown, it couldn't detect it.

I’m using 3.6.1 and haven’t seen anything related to slowdowns in the status window.

after a reboot of Windows, what is the pystone performance reported by SABnzbd? If that is high after a restart, then I'm guessing some process is junk your CPU power.

Pystone is the same, but performance is much better. Still good today 1 day after reboot. I’ll see if I can figure out what might be causing the slowdown. Something to do with the way Windows prioritizes processes maybe?

[guitarboy]

I think I may have fixed this problem with the SG TCP Optimizer. I simply selected the highest connection speed (100+ Mbps) and chose the "Optimal" setting. Since doing so I haven't experienced a slowdown. I'll post any relevant updates to this thread.

P.S.: I have an older Dell laptop but a newer USB wired adapter. My rated download speed from my ISP is 1 Gbps. With the change to the driver I'm getting a much higher Pystone (216154 vs. 63938).