SABnzbd Forums

Hi,

I'am using a Acer H340 Homeserver with sabnzb and my download rate isn't stable. It jumps from 2.2 mb/sek to 3,7 mb/sek everytime when I download files over usenet. The internet connection is fine. When downloading a file from a good Server I'm getting the non stop full speed of 3,7mb/sek. The same witch Rapidshare for example.  I'm using lightning usent with 100mbits and my internet connection is 32 mbits. The CPU load of the server is 80%.

Please help

If you set a decent article cache in Config->General (like 150M)
you should be able to get a speed of about 5-6 MBytes/sec.
I do with the same hardware.
The high CPU load is normal and the CPU is often the bottleneck after
you take away the disk channel load with the cache.
Also make sure that your temporary folders are not on a network path
(so like \\server\share, but instead directly on d:)

You read this?
http://wiki.sabnzbd.org/how-to-install-on-whs

Hi,

Thanks for your reply. Yesterday I've installed sabnzb+ 0.6.0 RC2 with the installer on D:\sabnzb. The installer went just fine. Then I've changed the temporary folders to e.g. "D:\sabnzb\temporary_downloads" or "D:\sabnzb\admin" General I've changed the Artile Cache Limit to 150M.

But now I have nearly the same problem. Downloads jump from 3,0 to 3,7 mb/sec. Are 700kb/s normal?

Next tuesday I will get my 100 mbits connection and I will check if the download breaks the 3,7mb/sec threshold.

0.6.0 has the cache folder per NZB inside the job folder in d:\sabnzbd\temporary_downloads.
"admin" keeps all other administrative files.
Stability of speed is determined by many factors.
Your Usenet provider is an important factor too.
Is is it fast enough, did you find the right amount of connections?
Too few and it's slow because often each connection has a limited speed,
too many and it slows down due to overhead.
The optimum is different for each Usenet provider.
Don't believe that 50 is better than 20, that's just marketing.

A quick check is to put SABnzbd on a PC and download from there.
CPU cannot be a true bottleneck on any normal PC less then 3 years old.

Okay, I'll give it a try. I think 3,2 ghz Quad Core is enough for testing . My provider offers 8 connections.

I have been struggling with this same issue for the last few days.  So far I'm having to throttle my speed down to 1.5MB/s and use a cache of about 700M for the speed to remain constant.  I have tested with newsleecher and am able to pull constant speed in the 4.5MB/s - 6MB/s range.  I really do like SABnzbd over newsleecher, I just wish I could get good consistant speeds.  Also I use an app called bitmeter to show network activity, I am not just relying on the sabnzbd UI to tell me my speed.

Weird, I have no trouble on any system to go above 4 MByte/sec, up to 11 for the fastest (plain dual core).
If it wasn't for newsleecher's higher performance, I would suspect something in your network setup.

BTW: What is your average download rate?
Having a constant speed is not a goal in itself.

My average download rate with newsleecher is about 4.5MB/s depending on time of day mostly.  A friend of mine visited at one point and was getting an average rate of about 7MB/s on his machine, which I reckon my lower speeds are more due to I/O deficiencies with WHS and possibly time of day as well.  

Also I did some more testing and found that I can actually go full bore with sabnzbd if there is no post-processing going on.  Once post-processing begins on a download if I do not limit my speed it will quickly fill the cache, regardless of size, and then gets speed spiking.  Clearly this is related not being able to write from the cache fast enough, thus I see speed going from full to 0 and back to full.

I guess it is possibly that somehow newsleecher is prioritizing download cache writing over verifying/unpacking type tasks?

I am just trying to give you as much info as possible.  Let me know if you want me to do any further testing for you.

I also posted a feature request that goes along with this issue, which is instead of totally pausing during post processing, be able to use an alternate download rate while post-processing.

edit: Now that I think about it.  Does SABnzbd do its post processing in the incomplete folder or does it do post processing in the complete folder location?

edit 2: Why do you disallow the temp download folder to be located on a UNC path?  In newsleecher I have it set to download to a share on my WHS that is NOT duplicated, and have no issue.

SABnzbd uses more CPU than newsleecher, so this may explain the spikey download during post processing.

The reason we don't allow UNC for the temp folder is that par2 cannot handle that.
BTW: UNC paths have more overhead.

without multi-threading sabnzbd is using TOPS 20% cpu, so that is not the issue.

so, my download speed with my acer 340 ist still the same  (3,0 MB/sek averrage). With my desktop pc I get 11-12 Mb/sek download speed. Is there any solution to get a higher download speed with my acer homerserver ? maybe a small tutorial?

I can only offer my recipe:
- Run as service
- Setup an ample article cache
- Setup sufficient amount of server threads (but don't overdo it)
  I have 10 threads for GigaNews.
- Use a folder the D: drive for all temporary data