Page 1 of 2

Download speed affected by queue / file size

Posted: July 21st, 2010, 5:31 pm
by x0x
I'm running SABnzbd+ 0.5.3 on Mac OS X 10.6

When I queue 100GB for example, my download speed goes down dramatically. What would be a good solution? I get the feeling that this does not happen with small queues / small files.

Re: Download speed affected by queue / file size

Posted: July 22nd, 2010, 3:18 am
by shypike
There is some influence.
You should set the refresh rate of the UI to something above 8 seconds.

Re: Download speed affected by queue / file size

Posted: July 22nd, 2010, 3:42 am
by x0x
shypike wrote: There is some influence.
You should set the refresh rate of the UI to something above 8 seconds.
I do not have a browser open when downloading, could this still be the problem?

Re: Download speed affected by queue / file size

Posted: July 22nd, 2010, 5:32 pm
by shypike
Not really.
Next time the queue is empty, stop SABnzbd and wipe all files from this folder:
/home/user/Library/Application Support/SABnzbd/cache

Re: Download speed affected by queue / file size

Posted: July 22nd, 2010, 6:37 pm
by x0x
Ok, the cache was clean but I think I found the problem.

As soon as I've queued some blu-ray movies (many gbs each), the download speed becomes slower at the moment releases are waiting to be processed after downloading. I have a fast internet connection so the repairing / unpacking process does not keep up with the downloading.

When this happens, the cache folders grows insane and when I look at the connections page of SAB, I can clearly see it cannot keep the connections opeb and disconnects constantly. That explains the low speed.

What can I do about this? I might try "Pause Downloading During Post-Processing" right?

Re: Download speed affected by queue / file size

Posted: July 23rd, 2010, 2:18 am
by shypike
Either "pause-during-postproc" or delayed post-proc will work.
If the cache folder keeps growing, that means that downloading keeps working
but that assembling the fragments into files is too slow work.
Quite an unexpected result.
Do you use an article cache (Config->General)?
This will save a lot of disk access.
I wouldn't be surprised if the true bottleneck is the hard drive.
Unfortunately OSX doesn't have ionice, which lowers the disk priority of par2 and unrar.

Re: Download speed affected by queue / file size

Posted: July 23rd, 2010, 4:27 am
by x0x
I am not using an Article Cache Limit. What would be a good idea?

The problem is my internet connection is maybe too fast for the computer SAB is running on. It downloads at 120mbit and at a sudden moment there are multiple 10+gb releases queued up for repair. This makes the cache folder enormous in size and SAB has real issues setting up new connections to download when that happens. Which makes the speed go down to almost nothing.

Re: Download speed affected by queue / file size

Posted: July 23rd, 2010, 5:09 am
by rAf
What's your folder config ?
Are you using smb shares or ext hdd ?

Re: Download speed affected by queue / file size

Posted: July 23rd, 2010, 5:12 am
by x0x
The "Temporary Download Folder" is on the machine itself, the "Completed Download Folder" is an SMB share. It's located on a QNAP NAS. My whole network is gbit with cat6 cables and router/switches.

Re: Download speed affected by queue / file size

Posted: July 29th, 2010, 3:14 pm
by x0x
Same problem, how bigger the queue how slower the download speed. I have no idea....

Re: Download speed affected by queue / file size

Posted: December 20th, 2010, 6:17 am
by royverkuylen
Hi all,

Sorry to bump an old post but I have the same issue.

I have a 120mbit connection and when I download something large (20GB) the download speed drops from 5MB/sec - 10MB/sec to 1MB/sec -2MB/sec.
Pretty frustrating because this actually means I cannot utilize the full bandwidth of my ISP.

I download to a download disk (same machine) and upon completion everything is moved to my raid array (same machine). It looks like SABNZBD cannot keep up with the processing part.

Article cache limit is set to 128M. Memory on machine is 2ghz.

Any idea how I can make use of my full download speed again with SABNZBD?

Thanks :-)

Re: Download speed affected by queue / file size

Posted: December 20th, 2010, 9:30 am
by shypike
Which release are you using?
Where is your 'cache' folder located?
Not on the RAID hopefully.
Also is this something like one 20G job or more 20 x 1G?

Re: Download speed affected by queue / file size

Posted: December 20th, 2010, 11:41 am
by royverkuylen
Hi Shypike,

I'm using version 0.5.6. The cache folder is not located on the RAID itself. It's on a separate disk with the incomplete, cache, log and watched folders (download/par disk). It's not on the disk where SABNZBD is installed though (OS disk).
Should I move it to the OS HDD instead?

It was a one 20G job. The first attempt did not have enough Par files so I downloaded a new one that average 5MB/s, which is fine.
Now I am downloading all 11 episodes of Planet Earth (11x 8.7G) and now it's killing itself again with an average download speed of 1MB/sec.

Many thanks for your help!

Re: Download speed affected by queue / file size

Posted: December 20th, 2010, 3:44 pm
by shypike
Should have asked before.
What's the OS?

Re: Download speed affected by queue / file size

Posted: December 20th, 2010, 4:42 pm
by royverkuylen
I run Ubuntu Server 10.10.

My average download speed is still 1.2MB. Already for about 6 hours with the same queue active. It has to be something with SABNZBD and large files because when I use Alt.Binz as application (e.g. on my windows notebook) I always have full download speed.

When I am just downloading one file with nothing in queue I usually get max. download speed.

Any thoughts on what could be the issue Shypike?