Download performance issue when using 1.1.0 over VPN

Report & discuss bugs found in SABnzbd
Forum rules
Help us help you:
  • Are you using the latest stable version of SABnzbd? Downloads page.
  • Tell us what system you run SABnzbd on.
  • Adhere to the forum rules.
  • Do you experience problems during downloading?
    Check your connection in Status and Interface settings window.
    Use Test Server in Config > Servers.
    We will probably ask you to do a test using only basic settings.
  • Do you experience problems during repair or unpacking?
    Enable +Debug logging in the Status and Interface settings window and share the relevant parts of the log here using [ code ] sections.
Post Reply
manders
Newbie
Newbie
Posts: 4
Joined: September 17th, 2016, 5:02 pm

Download performance issue when using 1.1.0 over VPN

Post by manders »

tldr; 1.1.0 performance issue related to connection count and VPN.

I thought I was going crazy!!! ???

Version 1.1.0 introduced a performance bug when downloading over VPN. At first, I just figured my VPN provider was having transient issues, but after I eliminated that as a problem, I ran a bunch of different tests using both 1.1.0 and the prior 1.0.3 version.

Code: Select all

Version     Connections     Normal  VPN
=========================================
1.1.0           30          6.4MB   48KB
                15          2.9MB   37KB
                 8          1.4MB   32KB
                 6          1.1MB  650KB  ***

1.0.3           30          6.2MB   2.0MB
                15          3.3MB   1.3MB


(The *** is not a misprint: the speed jumped when the connections were lowered!)

I'm running on Windows. The 1.1.0 upgrade was done "in-place", but I performed my tests by downloading the 1.0.3 binaries, placing them in a peer folder under \Program Files(x86), and then changing the folder names to swap back-&-forth between versions to do the testing.

I've reverted to 1.0.3 for the time being, but I kept my "test infrastructure" ;) in case y'all need me to test something.

[NOTE: My usenet provider supports up to 30 connections, I did not attempt to test any more than that.]
User avatar
shypike
Administrator
Administrator
Posts: 19774
Joined: January 18th, 2008, 12:49 pm

Re: Download performance issue when using 1.1.0 over VPN

Post by shypike »

As you can see, 1.1.0 is faster for normal connections when you use many connections.
(Upto 1.0.3, going above 15 meant lower performance.)
That's what we tweaked the code for.
It seems that for some non-standard situations (like VPN) it is counter-productive.
The trouble is, there are dozens of VPN solutions, each with their own behaviour.
We'll see if we can provide some more tuning options, so you can make this problem go away.
In the mean time, you're stuck with 1.0.3
User avatar
safihre
Administrator
Administrator
Posts: 5338
Joined: April 30th, 2015, 7:35 am
Contact:

Re: Download performance issue when using 1.1.0 over VPN

Post by safihre »

Can you check your CPU usage when on VPN?

Also, it makes almost no sense to use VPN for Usenet. Just use SSL to your newsserver and your provider has no way to track what you're downloading.
Externals/provider can only see that you connect to your newsserver's IP-address, but what can it possibly do with that information?
If you like our support, check our special newsserver deal or donate at: https://sabnzbd.org/donate
manders
Newbie
Newbie
Posts: 4
Joined: September 17th, 2016, 5:02 pm

Re: Download performance issue when using 1.1.0 over VPN

Post by manders »

safihre wrote: ... what can it possibly do with that information?
Sure ... you say that now ... ;)

I'll play around some more and get some CPU info for you.

Thanks for the speedy reply.
manders
Newbie
Newbie
Posts: 4
Joined: September 17th, 2016, 5:02 pm

Re: Download performance issue when using 1.1.0 over VPN

Post by manders »

shypike wrote: The trouble is, there are dozens of VPN solutions, each with their own behaviour.
Agreed! I guess I'm kinda sorta glad that this is by-design ... :P

shypike wrote: In the mean time, you're stuck with 1.0.3
Gosh ... twist my arm why doncha!!! 8)

Thanks for creating a cool product!
TheMaxxz
Newbie
Newbie
Posts: 6
Joined: September 21st, 2016, 5:21 am
Location: Belgium

Re: Download performance issue when using 1.1.0 over VPN

Post by TheMaxxz »

Hi,

I'm seeing a similar issue with speed drop when going from 1.0.3 to 1.1.0 but I'm not using a VPN. My connection is a VDSL line.
Running on Linux and I noticed that with 1.1.0 it seems the Recv-Q aren't getting read fast enough which seems to be causing the issue.

With 1.0.3 I was able to saturate my line with 20 connections. With 1.1.0 I upped it already to 30 but it's still not back at full speed.
manders
Newbie
Newbie
Posts: 4
Joined: September 17th, 2016, 5:02 pm

Re: Download performance issue when using 1.1.0 over VPN

Post by manders »

TheMaxxz wrote:With 1.1.0 I upped it already to 30 but it's still not back at full speed.
For my 1.1.0 testing, I backed it down to 8 and then 6 and got much better performance than I did with higher connections. Have you tried that?
Post Reply