Very low ssh connection speed (on OS higher than 6.2.4)

[Retired_Member]

Hi,

Some time ago I realised that during synchronising data between NAS and computer speed is very low. Situation happens only whe I use ssh connection, like rsync or midnight commande via WiFi and LAN also. There is no problem when I copy via Windows interface like 

Please check attachment.

6.4.2 - 28KB

6.6.1 - 13KB

One day I have done factory reset, downgraded to 6.2.4 and then tested again, on that version there is no problem.

6.2.4 - 10MB

Currently, because of some reason I run 6.6.1 and problem still happens, I even tested the newest version: 6.7.0. T206 and the problem is still the same.

Please advice me, maybe some settings (like bandwitch) are changed in new OS, why there is so huge difference between copying method?

I'm ready to do factory reset and test it again, but I already tested 4 version and problem is everywhere

[mdgm-ntgr]

Have you checked the load on the system e.g. using

# top

[Retired_Member]

At taht time, I didn't use any program to check, but I tested it many times on different conditions, I don't think that is problem for example hi CPU usage at the same time when I was copying.

No any apps installed, no any jobs, backups, only ssh and midnight commander running.

[mdgm-ntgr]

Is the software you use for SSH on your PC up to date?

[jak0lantash]

Are you sure you didn't use plain rsync when you got higher speed on 6.2.4 in comparison to rsync over SSH now?

On an RN102, I wouldn't expect good performance on any compressed or encrypted data flow. Its CPU is just too weak to sustain high throughout.

(I can't see the screenshot because it wasn't approved yet).

[mdgm-ntgr]

I just approved the screenshot.

Just thought of something that might help. I've sent you a PM.

[Retired_Member]

I use putty (ca't check version now, I will send it later) is version important, if I use always the same?

[Retired_Member]

I use putty (ca't check version now, I will send it later) is version important, if I use always the same?

[Retired_Member]

I confirmed that the same situation (low speed) happens when I mount share (SMB):

mount -t cifs -ro username=xxxxxxxxx,password=xxxxxxxx-o nounix,iocharset=utf8 //karol-komputer/data/ /mnt/karol-komputer/

and then copy copy via:

a) midnight commander - like previous screenshots

b) rsync:

rsync -rot --delete --progress /mnt/karol-komputer/ /data/Backup/karol-komputer-mirror/

[Retired_Member]

Does anybody have an idea? If I install 6.2.4 problem disapears, it looks like it is software or some settings problem.

[Retired_Member]

I downgraded again to 6.2.4 and you can check the results (I changed nothins in my network installation, notebook, anywhere), just downgraded:

[mdgm-ntgr]

For transfers on your LAN using SSH is overkill and over the internet the upload speed would probably be the bottleneck.

[Retired_Member]

I'm affraid that I don't fully understand you.

Do you think that SSH and Internet speed is problem? these two things are not connected with my issue, because:

1) I copy my files over ethernet (local network) not ovet the Internet I have gigabit network, so there is no bottleneck. NAS <-> SWITCH <-> NOTEBOOK

2) I map network drive of NOTEBOOK with cifs, and then I use the same RSYNC program, as ReadyNAS OS to sync files (my command is like: rsync -rot --progress /mnt/1/ /data/2/ (process is the same as ReadyNAS OS - backup jobs)

3) I don't use SSH to copying (screen in midnight commander was just an example), I use SSH to start srcipt (rsync command) ONLY, and then I use RSYNC

4) even if some of you think that it is SSH problem, I have tried start RSYNC in cron, and the speed is the same

It there is bottleneck somewhere, so why 6.2.4 works with 15MB speed and 6.6.0 with 23kB?

[jak0lantash]

The title of this thread is very misleading as it says "slow SSH", combined with the mention of "rsync", in the description it suggests that you're using "rsync over SSH", which can indeed have significant impact on performance on a weak CPU such as the one in an RN102.
Also, I presume you mean 15MBps for 6.2.4 and 23kBps on 6.6.0, which is again not the same.

Is your notebook running Windows 10?
Can you benchmark the sequential read speed from the mounted share on 6.6.0?
In you write to the NAS from the notebook, what's the performance?

[Retired_Member]

That's true, my title of topic is a bit different. I use Windows7, Intel core i5 and SSD.
I can do the tests but currently its not possible.
But still I cant understand why dont you think is OS/settings issue?
Environment is 100% the same.
Even if i use rsync over ssh or problem is on cpu performance in RN102, then those two things are of course not depend on OS version, if cpu is weak, it is weak on 6.6.0 and 6.2.4 also.

[jak0lantash]

Not necessarily. The same way as a weak CPU may be able to run Windows XP but struggle with Windows 7. I'm judging any Firmware or software version, just trying to make a point.
Anyway, even if the point is to "prove" that there is (or not) an issue on 6.6.0 compared to 6.2.4, narrowing down the root cause is still necessary.

[Retired_Member]

@jak0lantash

I understand. So could you desrcibe what tests should I do to find root cause?

Should I use specific sw to prepare test? is enough if I use IFTOP, or cbm (Color Bandwith Monitor)?

I would like to prepare all test on the begining, because downgrading (factory reset) takes a bit time.

		6.2.4	6.6.0
RSYNC	Read from NAS	...	...
RSYNC	Write to NAS	15MB/s	23kB/s
SSH (MC)	Read from NAS	…	…
SSH (MC)	Write to NAS	…	…
SMB	Read from NAS	…	…
SMB	Write to NAS	…	…
…	…	…	…

Should I test something more?

[Retired_Member]

I have done tests on versions 6.2.4 and 6.5.2, below you can find results:

As you can see, problem starts from 6.5.2, and happens, olny on rsync copying.

It's not SSH problem, I used SSH (putty) just to check speed, but copying was via OS backup job.

Please check copying speed (OS backup job) in your NAS.

I can't attach zip files, and I don't want to attach 8 screens, if you want I can send all.

All my tests was done on LAN connection, I have checked WiFi and on 6.5.2 and rsync copy speed is about 2.5MB, so the max speed of my WiFi.

It looks like problem happens on LAN (wired connection), of course I checked all cables, and computers, also changed router, even connected notebook directly to NAS ans still about 30kB on 6.5.2...

[mdgm-ntgr]

Well you can send the logs in following the instructions in my sig.

Have you tried disabling IPv6?

[jak0lantash]

Interesting. Do you have another NAS or Linux machine to cross-test and compare ?

[Retired_Member]

@mdgm-ntgr
Which logs exactly? What does it mean in my sig?
I have IPv6 disabled.

@jak0lantash
I have only one NAS, currently know nobody who has RN102.
I thought Technical Department of Netgear may have and do this thests. Actually model RN102 is not so old.

[jak0lantash]

@mdgm-ntgr means for you to check his signature for the procedure for sending (log) files to him.

If you want Tech Support to investigate something, you'll have to contact Tech Support... Meanwhile, if you want this community to help, we can suggest tests to help narrowing down the issue. If you don't have another machine to perform cross-testing, then this is not the right approach. The idea wasn't to use another RN102, but to access the share of your PC from that 3rd machine and test performance, then access a share of this 3rd machine from the RN102 and test performance.

So far, there is evidence that there is a performance difference between both firmwares on the RN102 in your environment, but that doesn't say that it's a FAULT on the NAS. It certainly does not mean that all RN102 owners are globally affected either. It may simply mean that there is a config parameter to adjust somewhere for some reason.

The next steps are up to you, investigate to further narrow down the issue in your environment or contact Tech Support.

[Retired_Member]

Hi,

Is really hard to decide which answer was a solution so I wolud like to thank to: mdgm and jak0lantash.

I was testing so many options and configuration and I fould the solution (problem). After Windows 7 update transfer is 10MB/s.

I dont really know which update package was responsible for it (in Windows 7, there was many updates pending) but for sure some updates and restart solved problem.

Now OS 6.6.1 and SSH connection gives me vero good speed.

[jak0lantash]

Thanks for sharing what solved your issue! That might be useful to somebody else 🙂