Suddenly very slow download speed

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morpheleon
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Re: Suddenly very slow download speed

Post by morpheleon »

I've seen this too. I'm on gigabit internet and I'm seeing what I call a saw tooth performance. sabnzbd will peak at maybe 6-10MB/s, and then trail off slowly down to the 100's of KB/s, and then it'll shoot back up and then trail off. It just does that repeatedly now. I've tried bumping up resources to multiple vCPU's and more RAM even though the VM had plenty to begin with. sabnzbd is also writing to an SSD so it's not a storage IO bottleneck either. I've also tried this on SSL and non-SSL connections and standard and non-standard ports.

Cmtaynbk
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Re: Suddenly very slow download speed

Post by Cmtaynbk »

morpheleon wrote:I've seen this too. I'm on gigabit internet and I'm seeing what I call a saw tooth performance. sabnzbd will peak at maybe 6-10MB/s, and then trail off slowly down to the 100's of KB/s, and then it'll shoot back up and then trail off. It just does that repeatedly now. I've tried bumping up resources to multiple vCPU's and more RAM even though the VM had plenty to begin with. sabnzbd is also writing to an SSD so it's not a storage IO bottleneck either. I've also tried this on SSL and non-SSL connections and standard and non-standard ports.
Is there a fix to this "saw tooth" issue? I have just installed a new NAS and I have been pulling my hair out thinking it was the new unit. I am seeing exactly what you are describing.

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safihre
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Re: Suddenly very slow download speed

Post by safihre »

Besides the things mentioned in this thread, I found something else that helps:
Lower the number of retries (Config > Switches) and lower the timeout on each of your servers to something like 20sec.
Especially that last one helped a lot for me, since it wouldn't take SAB 2 minutes (default is 120 sec) to decide to give up on an article.
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ALbino
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Re: Suddenly very slow download speed

Post by ALbino »

safihre wrote:Besides the things mentioned in this thread, I found something else that helps:
Lower the number of retries (Config > Switches) and lower the timeout on each of your servers to something like 20sec.
Especially that last one helped a lot for me, since it wouldn't take SAB 2 minutes (default is 120 sec) to decide to give up on an article.
I'm not sure about 0.8.x, but in 0.7.20 the lowest you can set the timeout to is 30 seconds, for what it's worth. And yeah, lowering the timeout was the best thing I ever did to help SAB feel like it's hanging less.

syphonx
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Re: Suddenly very slow download speed

Post by syphonx »

Anything further on this, changes mentioned don't seem to help much

heisenberg
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Re: Suddenly very slow download speed

Post by heisenberg »

I have the same Issue but it is very strange

I am using on my QNAP 451+ Sab : 1.0.0RC1
and on a Notebook with Debian 8 Sab : 08.x

The QNAP is much faster in CPU and Download folder speed of 92.5 MB/s but now the strange happens.

The Debian 8 Version Downloads with 25mb/s what ever nzb file
The Qnap on same Network only works with 7 -10mb/s with am RAM usage of 8 % and CPU load of 15%

Can somebody helps me ?

I used for Installing : http://apps.qnap.community/11-community/4-sabnzbdplus with Qpkg file. Same Issue when installing direkt von GIT Hub
On the Debian i installed it with GIT Hub to.

Notebook : Debian 8
Python 2.7.3 (default, Mar 14 2014, 11:57:14)
[GCC 4.7.2] on linux2
Type "help", "copyright", "credits" or "license" for more information.

QNAP : ENTWARE-NG 0.96
Python 2.7.11 (default, Jan 9 2016, 16:55:40)
[GCC 4.8.5] on linux2
Type "help", "copyright", "credits" or "license" for more information.

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shypike
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Re: Suddenly very slow download speed

Post by shypike »

heisenberg wrote: The Qnap on same Network only works with 7 -10mb/s with am RAM usage of 8 % and CPU load of 15%
What kind of network card does it have?
Is it 10, 100 or 1000 Mbps? Is it actually working at its highest speed?

BTW: SABnzbd always shows its speed in Bytes/sec, not bits/sec (used for network interfaces).

heisenberg
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Re: Suddenly very slow download speed

Post by heisenberg »

2x 1000mb /s
1 card connected with 1000mb

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shypike
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Re: Suddenly very slow download speed

Post by shypike »

Have you tried other network-intensive software on the device?
Normally SABnzbd is limited by CPU speed, not network speed.
I cannot think of a reason why this would happen.
Only one network connection is used?
What is the speed in MBytes/sec? (Because you used mb/s).

heisenberg
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Re: Suddenly very slow download speed

Post by heisenberg »

Sorry it is connected with 1 Ggps

79.0 MB/s using Samba / NFS / FTP

I am Using a TS-451+ with 8 GB Ram

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shypike
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Re: Suddenly very slow download speed

Post by shypike »

Have you set an article cache in Config->General ?
Set it to 150M or 200M, if you have plenty of memory.

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sander
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Re: Suddenly very slow download speed

Post by sander »

@heisenberg:

Could you do two things on your QNAP NAS:

In SAB's GUI, under "Status and interface options" (upper right corner), click on the "Download folder speed" refresh icon. What is the disk speed? Post the output here.

Code: Select all

git clone https://github.com/sivel/speedtest-cli.git
cd speedtest-cli
./speedtest_cli.py
... that will give the speed in Mbps. Divide by 10 to get MB/s. Post both here.

heisenberg
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Re: Suddenly very slow download speed

Post by heisenberg »

sander wrote:@heisenberg:

Could you do two things on your QNAP NAS:

In SAB's GUI, under "Status and interface options" (upper right corner), click on the "Download folder speed" refresh icon. What is the disk speed? Post the output here.

Code: Select all

git clone https://github.com/sivel/speedtest-cli.git
cd speedtest-cli
./speedtest_cli.py
... that will give the speed in Mbps. Divide by 10 to get MB/s. Post both here.
Result Speedtest-cli

Code: Select all

Testing download speed........................................
Download: 197.97 Mbit/s
Testing upload speed..................................................
Upload: 20.32 Mbit/s
SABZ Status and Interface :

Code: Select all

Local IPv4 address :
Public IPv4 address : 176.198.xxx.xxx
Nameserver / DNS LookupOK
Download folder speed : 85.0 MB/s  (/share/Download/sabnzbd/i…)
Complete folder speed : 72.7 MB/s  (/share/Download/sabnzbd/c…)
Used cache 0B (0 articles)
Settings:
Article Cache Limit : 2G

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sander
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Re: Suddenly very slow download speed

Post by sander »

Your speedtest looks good, diskspeed too.

Maybe the following is useful for you:


On my own Raspi (with a very low spec CPU), I only get 1.2 - 1.9 MB/s, whereas the CPU is still 33.3% idle.

My linespeed

Code: Select all

Testing download speed........................................
Download: 35.78 Mbit/s
Testing upload speed..................................................
Upload: 23.53 Mbit/s

However:
CPU load average is high (as: > 1): Sysload: 5.69 | 4.32 | 3.49. That is a signal the CPU is indeed overloaded. You can see in the upper right corner of SAB's GUI of the Plush interface (or use "uptime" on the Linux command line)
I think Python and thus SABnzbd will only use one CPU core.

Furthermore my disk speed (USB connected) is low: Download folder speed 9.6 MB/s (with SABnzbd paused). You can check that via "Status and interface options" in Glitter. What does your system tell you?

Finally: if you set SAB's logging to +Debug, SAB's sabnzbd.log will your CPU at startup:

Code: Select all

2016-01-04 22:53:37,421::DEBUG::[SABnzbd:1280] CPU Pystone available performance is 4073
2016-01-04 22:53:37,427::DEBUG::[SABnzbd:1285] CPU model name is ARMv6-compatible processor rev 7 (v6l)

Code: Select all

[email protected]:~# top -bcn1 | head -10
top - 18:42:19 up 59 min,  2 users,  load average: 3.69, 3.58, 2.87
Tasks: 100 total,   1 running,  99 sleeping,   0 stopped,   0 zombie
%Cpu(s): 32.5 us, 13.7 sy,  0.0 ni, 33.3 id, 13.6 wa,  0.0 hi,  6.8 si,  0.0 st
KiB Mem:    493644 total,   480392 used,    13252 free,    16560 buffers
KiB Swap:        0 total,        0 used,        0 free.   288600 cached Mem

  PID USER      PR  NI    VIRT    RES    SHR S %CPU %MEM     TIME+ COMMAND
 2308 root      20   0  406372 119268   9544 S 56.5 24.2  13:28.13 /usr/bin/python -OO ./SABnzbd.py --server 0.0.0.0 -b0
 4214 root      20   0    5356   2392   2104 R 16.6  0.5   0:00.13 top -bcn1

heisenberg
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Re: Suddenly very slow download speed

Post by heisenberg »

2016-02-14 22:59:41,125::DEBUG::[SABnzbd:1284] CPU Pystone available performance is 25000
2016-02-14 22:59:41,125::DEBUG::[SABnzbd:1289] CPU model name is Intel(R) Celeron(R) CPU J1900 @ 1.99GHz

Download folder speed : 85.0 MB/s (/share/Download/sabnzbd/i…)
Complete folder speed : 72.7 MB/s (/share/Download/sabnzbd/c…)

Mem: 6535448K used, 1533744K free, 0K shrd, 68632K buff, 5607244K cached
Load average: 0.72, 0.86, 0.87 (State: S=sleeping R=running, W=waiting)



The top command give me an unsupportet error with -bcn1

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