Rwin Tweaks How do yo uset RWIN?

Raider4evr · Post by **Raider4evr** » Fri Jun 08, 2001 3:27 pm

Before doing any tweaks:
MTU=1500, MSS=1460, RWIN=17520, scaling=0 bits, uscaled receive window = 17520

Analyzer suggested changing RWIN value, so I entered the DefaultRcvWindow=256960 Key. When I go back to the Analyzer, is says :

Default Receive Window (RWIN) = 65535
RWIN Scaling (RFC1323) = 0 bits
Unscaled Receive Window = 65535
Note: Under Windows 9x, if you have RWIN set to any other value, and the Analyzer reports 65535 you might need to install the MS Vtcp386 fix.
For optimum performance, consider changing RWIN to a multiple of MSS.
Other values for RWIN that might work well with your current MTU/MSS:
513920 (MSS x 44 * scale factor of 8)
256960 (MSS x 44 * scale factor of 4)
128480 (MSS x 44 * scale factor of 2)
64240 (MSS x 44)

I changed the RWIN again, this time to 513920 and the analyzer gives me the same information. Should I be changing the "scaling" too? I didn't get the error without RWIN, and I thought once it was changed, it would reflect the value that I entered. Any help/clarification would be appreciated.

thanks!

cablenut · Post by **cablenut** » Fri Jun 08, 2001 3:54 pm

To use RWIN over 64240 you have to set Tcp1323Opts to "1" however most servers don't allow RWIN over 64240 so they scale any window over that down.

The follorwing RWIN are optimal:

513920 (MSS x 44 * scale factor of 8)
256960 (MSS x 44 * scale factor of 4)
128480 (MSS x 44 * scale factor of 2)
64240 (MSS x 44)

Raider4evr · Post by **Raider4evr** » Fri Jun 08, 2001 6:16 pm

Do you know why it keeps saying 65535 in RWIN, no matter what number I enter? Is this a default?

also, Where would I enter this: Tcp1323Opts to "1"
Do I make another entry in the same MSTCP folder?

Thanks!

Lobo · Post by **Lobo** » Fri Jun 08, 2001 6:18 pm

Do you have adjuster

What OS and system specs

Raider4evr · Post by **Raider4evr** » Fri Jun 08, 2001 6:22 pm

I haven't changed anything, except to add the RWIN line in the MSTCP folder. I am running WinME, 256 Megs of Ram, 700MHZ AMD chip and am connecting to internet via Media1 RR service. I ahve been able to d/l from the net at up to 300kb/s, but my u/l is like 32 - 35 max...I would like to speed this up....

Lobo · Post by **Lobo** » Fri Jun 08, 2001 6:24 pm

If I were you I would follow directions on help page below in signature, it will enter all the right values except RWIN which we will get to

Lobo · Post by **Lobo** » Fri Jun 08, 2001 6:30 pm

When you get back
Try these RWIN's (Default Rvc Window)
1 at a tine in box on adjuster inside 4.2 on desktop. GlobalmaxTcpWindowSize-BLANK
Save to registry at bottom and reboot each time you change value in adjuster
Check analyzer here at Speedguide to be sure you have RWIN in, thank you
Try: 513920, 522680 or 524176

Raider4evr · Post by **Raider4evr** » Fri Jun 08, 2001 6:33 pm

Well, after doing the Speadguide analyzer, it said the only recoomendation was to cahnge the RWIN, which I did. I've changed it twice once to 256960 and the second time to 513920. Both settings give me the same results in the analyzer when i test it - this is why i am wondering if I entered something incorrectly, or left something off.

I am getting this from the "Recommended wettings for Windows 98/98SE/WindowsME" section. Should I implement all the cahnges it suggests???

Raider4evr · Post by **Raider4evr** » Fri Jun 08, 2001 6:36 pm

Thanks for your patience....I will try making all the suggested changes in the section for WinMe. Then try the different settings for RWIN and see if the Analyzer shows any changes...

Lobo · Post by **Lobo** » Fri Jun 08, 2001 6:53 pm

After you save a setting on Cablenuts adjuster you must REBOOT

Lobo · Post by **Lobo** » Fri Jun 08, 2001 7:09 pm

Whatever you do, do not install 386th Fix patch, that is not for ME, if you did, do a search, find it, and delete it

Raider4evr · Post by **Raider4evr** » Fri Jun 08, 2001 8:20 pm

Lobo - thanks forthe help. cleaned registry back to defaults and then installed Cablenut program. Tried the adjuster with 4 RWIN settings: 64240, 513920, 522680 and 524176. I kept going back to the same FTP to upload and checked my upload speed. With each change, there was a bit of improvement over the previous settings.

My max upload before was 32-35 KB/s, and with the last 524176 RWIN value, it began at 78 KB/s, then slowly went down to 35/36 KB/s. can you keep increasing the RWIN values? Also, is there a way to keep the high value it starts out at?

tahnks for the help.