Slow network performance during file transfers

[Starbuck84]

The topic title is a little vague, couldn't come up with a better one. Sorry for that.

 

I've searched the forums and tried several options for the last couple of days and I haven't found a solution I want so far and I was hoping you guys could help me with the following:

 

When I cold boot my laptop (Windows 8 x64) and I wake my NAS, everything is fine. I copy my files from and to my NAS with a transfer speed of around 39 MB/s. I have a Synology DS213j. I know this NAS could do quicker, but my laptop is the bottleneck in this one. No worries, 39 MB/s is fast enough for me. But if my laptop is on for a couple of hours and I've copied several files from and to my NAS, the performance drops to around 5~6 MB/s and there is no way to get the previous 39 MB/s back, until I reboot Windows.

 

I tried the following:

* Router reset.

* NAS restart.

* Against better knowledge: replaced my UTP-cables.

* Updated my network card drivers.

* Changed several settings on my NAS, like enabling / disabling SMB2 and Large MTU support.

* Changed the setting of my network card to prevent it from entering "sleep" (using device manager).

* Changed the setting of my network card to force it to "full duplex / 1gbps" instead of "auto negotiation".

 

All to no avail. It only helps to reboot Windows. After the Windows reboot my network speeds is up to 39 MB/s again. It's like smb/cifs is "full" or just bogged down. This doesn't happen if I use my MacBook which uses AFP.

 

So I was thinking: is there a way to reset the network within Windows instead of doing a complete reboot? Like enabling / disabling a service using a script or some sort? Or if you know a solution to this problem, I'm all ears.

[duddit2]

Have you tried simply disabling and re enabling the network adapter?

[Starbuck84]

Seriously, I feel so stupid now. :P Actually, no I haven't. Will test this as soon as I get home, thanks for your reply.

[+BudMan MVC]

"It's like smb/cifs is "full" or just bogged down. This doesn't happen if I use my MacBook which uses AFP."

 

smb is full??  what??  I can safely say it is not ;)

 

Here is a question for you -- what is the speed of your connection show when you drop to 5-6 which is prob a 100mbit connection vs a gig connection.

[Starbuck84]

I meant smb/cifs cache is full/to many connections "left" open or something, I'm just guessing here. :) Find it rather strange my networkspeed just drops down like that. And no, the established connection stays at 1.0 gbps, according to Windows.

 

I was thinking the same thing, after a while the computer puts the NIC in hibernation and when it comes back it "auto negotiates" at 100mbps instead of 1.0 gbps. But that's not the case, at least according to Windows Networkcenter.

[+BudMan MVC]

"I meant smb/cifs cache is full/to many connections "left" open or something"

And what cache would that be or connections would that be. Sorry again no..

As to this..

Changed the setting of my network card to force it to "full duplex / 1gbps" instead of "auto negotiation".

You should NEVER have to hard code gig.. it should always be left at auto.. Only in the oddest troubleshooting sessions would you do that, and then you would put it back to auto.

So your laptop is wired only - or is possible your at some times using wired and other times wireless?

[Starbuck84]

I have no thorough knowledge of the SMB/cifs protocol, so I'm guessing as to why this happens. Good to know it can't be that. :)

 

I know gigabit should be set to auto, I tried forcing it as a gigabit connection just for testing purposes, but to no avail. It's back to auto now.

 

And no, I've thought of that, but I physically disabled my wireless adapter. (Touch sensitive switch on the laptop itself). Just to be sure, I also removed my own network from prefered networks within Windows. So even if the wireless card does power on somehow it won't be able to connect to my network.

[+BudMan MVC]

Well would need to see it happen to try and figure out what is going on..

 

When it happens can I team viewer in?

 

can you do a robocopy of a file from your nas to see the normal speed..

 

 

So this is copy of a 900MB file from my nas, as you can see I got 81MBps..  So can we see this copy while its good, and then when speed is bad..

[Starbuck84]

Thank you +BudMan! Tonight, when I get home from work, I'll do a robocopy of a random generated (using /dev/urandom) 700mb file when I get home (so the speed is ok) and after a couple of hours and when it happens again, I'll do a robocopy of the same file and post the results.

[+BudMan MVC]

sweet -- real curious on the details of that test.

[Starbuck84]

Here are the results.

 

Steps:

* Powered on my laptop and copied a (somewhat) 600 MB file to my NAS. Results are in the first screenshot.

* Left my laptop powered on and came back roughly 1 hour and 45 minutes later. Removed the file from my NAS and exeuted the exact same robocopy command using the up-arrow key in CMD. Results are in the second screenshot.

* Screenshot 3 shows my network speed after both tests, still at 1.0gbps, but as you can see, my speed dropped drastically. To get the full speed back I had to reboot my laptop. Before I did that, I reset my router, restarted my NAS, all to no avail. Reboot Windows and voila, I'm back on my initial transfer speed from screenshot 1.

 

Screenshot 1:

 

Screenshot 2: Same file transfered after roughly 105 minutes:

 

Screenshot 3: Windows still shows me my network operates at 1.0gbps:

[+BudMan MVC]

So did the laptop go to sleep mode, hibernate mode?  With 11MBps I would say your in 100mbit connection.

 

If it did - then try and force it, do a speed test..  put the thing to sleep/hibernate and then bring it out and do the test again.

 

What is the specific nic, and what is the driver your using?   What is this exact laptop model, bios version, etc..

 

I have to assume this happens after laptop has been to sleep..

[Starbuck84]

Thank you for your quick reply!

 

It's an Acer Aspire 6930G (734G32Bn). Latest official BIOS version: 3238. The NIC in this laptop is broken, so I'm using an USB NIC from Sitecom. It's an Sitecom LN-032 (USB to Gigabit LAN), which is just a rebrand of an ASIX AX88179 controller. I've tried Sitecom's drivers v1.001 (the only driver for WIndows 8, which is based on the ASIX 1.16.5.0 driver) and the latest general ASIX 1.16.9.0 driver. Both drivers produce the same result.

 

The laptop is set to "High Performance" in Windows with all sleep / hibernate options disabled.

[duddit2]

The USB Nic throws a whole new light on this issue in my mind, now its not simply how windows controls the Nic (via driver) but we now have USB bus thrown into the mix and how power management is handling USB.

[+BudMan MVC]

^ yup I agree!!!  vs windows restart why don't you just pull the usb nic and reinsert it and test speed again.

 

In your power management advanced settings, even under high power profile usb is normally set to selective suspend.

 

BTW how/why do you know the nic in the laptop is broken?

 

That usb nic says it supports

Supports advanced link down power saving

And Supports IEEE 802.3az (Energy Effi cient Ethernet)

 

So yeah I would really have to think its a power saving feature - especially since you say it works great, and then after not using it go to use it again and its slow.

 

Looking at drivers for windows 8 I see

Version 1.0.1.1 (2012-12-21)
1. This setup program includes the following AX88179/AX88178A Windows 8 32-bit/64-bit drivers.
   AX88179/AX88178A Windows 8 32-bit WHCK driver v1.16.5.0
   AX88179/AX88178A Windows 8 64-bit WHCK driver v1.16.5.0
2. Added to support Sitecom's AX88179 VID/PID.

 

Is that the driver your using?  I really have to think this is a power savings/usb thing though.

 

Also isnt that a older laptop - I doubt it has USB 3 ports?  What kind of cpu usage do you see when its going fast and then again when its testing slow?

[Starbuck84]

Could that be it? Under device manager I've unchecked the option of the computer to put the NIC in standby. I was under the assumption it wouldn't do any power management from that moment on. But you both seem very confident that would be the cause, also I've looked into this "selective USB suspend" and that's something I'll experiment with. Next time it goes slow, I'll unplug and replug the USB NIC.

 

+BudMan: https://www.neowin.net/forum/topic/1155558-data-corruption-during-network-transfer/ . My on-board NIC constantly produces CRC-errors during file transfers.

 

And yes, that's the current driver I'm using. I know it's a somewhat older laptop and it doesn't have USB3, still this USB NIC is a lot faster than my wireless card, especially during multiple down and uploads. Haven't checked my CPU usage though, will keep a Task Manager screen open on the background. Thanks for the tip!

[Sikh]

Theoretical speed of USB 2 is 480Mbit/s. No way you can use a USB to Gig Adapter without having USB 3 to achieve full gig speeds. I had to buy one for my Surface Pro and I did a test between a USB2 adapter and USb3 adapter to prove to someone the difference and it was major. 

 

Also, your issue definitely sounds like a USB Sleep issue. I had to deal with on my surface until I disabled selective sleep / suspend on my usb3 port. It would after 5 or so minutes correct itself and start using the adapter at full power, but if you go into device manager and disable it, it won't slow down after waking it up from sleep anymore.

[Starbuck84]

I'm aware of the fact I'm not using the full speed while using USB2, that's ok. It's still a lot better than my wireless connection.

 

I already disabled the option in device manager, will try to disable "selective USB suspend" to see if that improves anything. :) Thank you all so far to narrowing down this issue.

[duddit2]

The option you have disabled stops the OS from putting the NIC to sleep, but the NIC is presented to the system via the USB Bus which has its own power management setting.

 

You should see the device under USB devices, change the power setting in there and see how it goes.

 

Another way as BudMan says is to simply unplug and plug back in the USB device, this will tell you instantly that the theory of USB power management is correct.

[+BudMan MVC]

So I somewhat recall that thread after rereading it - did you ever fire up wireshark and see what was happening in the actual transfer.. where you seeing garbage on the line, were you seeing retransmission?

I have never seen a nic fail where file speeds where good but files were corrupted.. Not saying it couldn't happen, just have never seen such a failure mode.

When a nic starts spewing out garbage the speed is usually terrible and everything would be effected, browsing the internet for example - not just file transfers.

It would be interesting to see a wireshark sniff of the transfer from say your usb nic of the file(s) and then sniff using the built in card.

I like the info about in like 5 minutes the usb nic would be back to full speed.. Vs rebooting the laptop or resetting the usb nic.. How about just doing multiple tests of the file transfer and see if after a couple minutes of use if it goes back up to your normal 30MBps speeds.

[Starbuck84]

Thanks for the clarification duddit2!

 

It's a first for me too +BudMan, but I exchanged cables, tried several speed settings, even forced it down to 10mbps and I still got CRC errors. The rest of the hardware is fine according to different tests. I'll have some extra time this weekend, so Wireshark is on my to-do list. :)

 

Regarding the multiple tests, they crossed my mind and are on my to-do list as well for this weekend.

[Starbuck84]

I left all options as they were and my speed dropped down again. I unplugged the USB NIC en plugged it back in. My speed was back to normal again. That's an improvement over rebooting! :)

 

I re-installed the latest 1.16.9.0 drivers from ASIX themselve instead of the Sitecom drivers. I disabled the option in device manager to let my computer power down the USB NIC. I found an option in device manager under the "Advanced" tab called "Selective suspend" and set it to "disabled". I left the "Selective suspend" enabled under Windows.

 

Last night, no speed drops. *taps on wooden table*.

 

Things still to do:

* Wireshark

* Keep on testing to see if the speed drops are really gone

 

So far things are looking good. The next few days I'm away on a business trip, so I'll be reporting back a little later.

[Starbuck84]

The good news: the speed drops haven't occured anymore! Disabling "selective suspend" did the trick. Something so simple, yet so powerful. I really, really want to thank you guys for all the thoughts and help.

 

A little help on the Wireshark I guess. A 5 minute live capture is enough for you diagnose any problems? I used Wireshark in the past, but I'm now at a total loss on how to diagnose any problems.

[+BudMan MVC]

How long does it take to copy the file?  I can not think its even 5 minutes?  Unless the thing is freaking HUGE, or something is really really wrong..

 

I could move like 24GB in 5 minutes ;)

 

Fireup wireshark -- start your capture..  copy your file.. Stop capture, and then get it to me and will take a look.  Thinking your copy of jpg takes no more than a couple of seconds.

[Starbuck84]

You're right and sorry it took some time to get back at this. The reason it took so long: there seems to be a new problem with my onboard NIC. As soon as I connect it to my router (built in switch), the green LED comes on, the orange LED comes on and both immediately go off. This keeps repeating itself. In the meantime I have no connection of course.

 

I tried different cables, even connecting directly to my router/switch (excluding my wall socket, which always works btw). I checked the pins inside the NIC's connector, all seem fine. According to Atheros this means there's something going on with the handshaking / auto setting of the NIC. I forced it to 10 and 100 mbps, no effect.

 

I don't want to waste any more of your time, my problem with my USB NIC is solved, for which I'm glad. I'll just leave it to that.