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murmel
03-08-11, 08:24 PM
Hi guys,
I am from germany, so please excuse me for my english.
I tried your SG TCP Optimizer 3.0.6 today for the first time and I notized, that "MTU" is always at "0". The Optimizer changes it to "1500" but after the reboot, it`s at "0" again.

My Connection is 16000kbps DSL with real ~11000kbps from T-Online (de), real upload is at ~1000kbps. The connection type is PPPoE. My OS is Windows 7 Professional SP1 x64 and it`s a legal version from MSDNAA, I am student.
I have a D-Link DGL 4300 Router and its MTU is at 1492.

I started the Optimizer as Administrator.

My question is, why does the MTU not change and if it`s normal, that it`s at "0" (especially when the router has the MTU at "1492")?

A second thing is, that I read a bit in "Tips for Beginners" and there always is this "RWIN" but I can`t find it in the Optimizer (only in the tap BDP, but that`s only to calculate, not to set it, isn`t it?) or in my router!?

Looking forward to hearing from you.

murmel
trogers
03-08-11, 09:46 PM
Do this test and post the report under the 'More Details' button:

http://nitro.ucsc.edu/

RWIN = TCP Window = Buffer
Rollingstone
03-09-11, 05:31 AM
Try Winsockfix !
murmel
03-09-11, 10:23 AM
@trogers: I can open the "More details"-window, but I can`t copy the text and the "Copy"-button is not clickable/greyed out.

Edit: Ok, I have no possibility to copy it, so I made screenshots:
http://www.abload.de/thumb/unbenannt1hk0r.png (http://www.abload.de/image.php?img=unbenannt1hk0r.png) http://www.abload.de/thumb/unbenannt2n8lk.png (http://www.abload.de/image.php?img=unbenannt2n8lk.png) http://www.abload.de/thumb/unbenannt3k8ah.png (http://www.abload.de/image.php?img=unbenannt3k8ah.png)
murmel
03-09-11, 11:45 AM
Because I have no possibility to copy the text, I made screenshots:
http://www.abload.de/image.php?img=unbenannt1hk0r.png
http://www.abload.de/image.php?img=unbenannt2n8lk.png
http://www.abload.de/image.php?img=unbenannt3k8ah.png
murmel
03-09-11, 07:04 PM
Btw.:
« SpeedGuide.net TCP Analyzer Results »
Tested on: 03.09.2011 19:59
IP address: 91.6.xxx.xxx
Client OS: Windows 7

TCP options string: 020405ac0103030201010402
MSS: 1452
MTU: 1492
TCP Window: 66792 (multiple of MSS)
RWIN Scaling: 2 bits (2^2=4)
Unscaled RWIN : 16698
Recommended RWINs: 63888, 127776, 255552, 511104, 1022208
BDP limit (200ms): 2672kbps (334KBytes/s)
BDP limit (500ms): 1069kbps (134KBytes/s)
MTU Discovery: ON
TTL: 49
Timestamps: OFF
SACKs: ON
IP ToS: 00000000 (0)

Don`t forget that I am located in Germany. I have much better results with german/european servers (ping, up-/download). ;)
Here is a result with a german server at speedtest.net: http://www.speedtest.net/result/1193404310.png
trogers
03-09-11, 09:08 PM
MaxMSS and MinMSS are both at 1452, thus your MTU is set to 1492.

Window 7 autotuning is set at normal - MinRwinRcvd - 260 and MaxRwinRcvd - 1040896
murmel
03-10-11, 07:21 AM
But why does the Optimizer shows me a MTU of 0? That is my question.
And what does my values for MaxMSS/MinMSS and Rwin mean in the end? Are these values ok for my connection?
I did these test with "optimal"-settings in the Optimizer (already used the optimizer yesterday and left the settings as they are with "optimal"). Did it optimize right?
Thank you for your help and explantations and sorry for my english again :)
trogers
03-10-11, 09:49 AM
But why does the Optimizer shows me a MTU of 0? That is my question.
And what does my values for MaxMSS/MinMSS and Rwin mean in the end? Are these values ok for my connection?
I did these test with "optimal"-settings in the Optimizer (already used the optimizer yesterday and left the settings as they are with "optimal"). Did it optimize right?
Thank you for your help and explantations and sorry for my english again :)

I think what you meant is that when you set the Optimizer into Optimal mode, there is no value shown for MTU.

When I use the Optimizer, I will first set it to Custom and enter the MTU value I desire. In your case, it will be 1492. Then I will set the Optimizer to Optimal.
murmel
03-11-11, 01:12 PM
Yes, the optimizer never shows a value for MTU for me. But I set it the way you posted and will test the optimized settings the next days.
Thank you for your help with this tool, it`s a great one and very easy to use. I just wanted to understand some things :)
See you next time and thx again.
Philip
03-20-11, 01:17 PM
The Optimizer 3.0.6 has a problem finding/reporting the correct MTU for some international versions of Windows, we're working on a fix for that. What language is your Windows version ?
RaisinCain
03-20-11, 02:21 PM
The "optimizer" should not be use with Windows 7 (possibly Vista and XP as well). It screws with settings that should be left alone.
murmel
03-20-11, 05:22 PM
And which settings are this? This would help Philip and his guys better.
Philip
03-20-11, 06:13 PM
The "optimizer" should not be use with Windows 7 (possibly Vista and XP as well). It screws with settings that should be left alone.

While you're entitled to your opinion, it does not necessarily coincide with the majority of other couple of Million users who've tried it...

We've invested quite a few years in researching and testing each setting in different environments, listening to feedback and fine-tunning the program for each Windows version individually. It is true that the Optimal settings may not be the best for each individual connection, that is why the tool allows for custom tuning.

If you have an issue with a specific recommendation, we welcome all feedback. The one "optimal" setting that may eventually change for next build is turning off ECN Capability under Windows 7, there are reportedly some issues with it and some ISPs.