Advice on the affects of More Ram

Mazakman · Post by **Mazakman** » Sat Jun 30, 2001 8:30 pm

Just boosted my ram up to 192 mb. It was previously 128 mb. I have been pretty happy with what I have been seeing speed wise with the following settings. I am on 128/3000 DSL connection here. Will the increase in ram affect what I should be trying as far as any of my settings are concerned ? Appreciate any help or advice. Thanks.

850 Athlon
192 mb ram
45 gb HD

TCP options string = 020405b40103030301010402

MTU = 1500
MTU is fully optimized for broadband.

MSS = 1460
Maximum useful data in each packet = 1460, which is equal to MSS.

Default Receive Window (RWIN) = 524176
RWIN Scaling (RFC1323) = 3 bits
Unscaled Receive Window = 65522
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)

bandwidth * delay product:
Your RcvWindow limits you to: 20967.04 kbps (2620.88 KBytes/s) @ 200ms
Your RcvWindow limits you to: 8386.816 kbps (1048.352 KBytes/s) @ 500ms

MTU Discovery (RFC1191) = ON

Time to live left = 49 hops
TTL value is ok.

Timestamps (RFC1323) = OFF

Selective Acknowledgements (RFC2018) = ON

IP type of service field (RFC1349)= 00000000

Lobo · Post by **Lobo** » Sat Jun 30, 2001 8:34 pm

You might try a RWIN of 531440 and see if it's better

Mazakman · Post by **Mazakman** » Sat Jun 30, 2001 8:59 pm

Thanks Lobo. 531440 feels very much like the 524176 that I was running. Of course I know that the best time to speed test is later on or early tomorrow.

Lobo · Post by **Lobo** » Sat Jun 30, 2001 9:02 pm

Yes try it late or tomorrow and see if it's better

Idiot Savant · Post by **Idiot Savant** » Mon Jul 02, 2001 3:17 am

Thats a huge Rwin, and it most likely wont show a big gain in speed. Try to configure your Rwin so that your usual speed is 80% of its theoretical max. Works great for me, and i get 7mbps with my 280320 Rwin. Bigger is not always better.

Lobo · Post by **Lobo** » Mon Jul 02, 2001 7:46 am

Big difference between 450 CPU and 85:)

HalfLifer · Post by **HalfLifer** » Mon Jul 02, 2001 7:46 am

Originally posted by Idiot Savant
Thats a huge Rwin, and it most likely wont show a big gain in speed. Try to configure your Rwin so that your usual speed is 80% of its theoretical max. Works great for me, and i get 7mbps with my 280320 Rwin. Bigger is not always better.

Exactly. Lobo seems to think so however.

Lobo · Post by **Lobo** » Mon Jul 02, 2001 7:57 am

Let the people decide what they like the best, you like 64240, fine, others like it higher, up to them

, and I guess SG is wrong to because they use 256960

Idiot Savant · Post by **Idiot Savant** » Mon Jul 02, 2001 4:08 pm

Lobo, all im saying is this...
Unlike your incredible connection (a good 1.5mb above mine)
most people in here usually only achieve speeds of 1-3mbps. In this case, a Rwin of ~256960 is great. That Rwin will carry you to incredible speeds, and the max that one value provides is far better than what most of them can hope to get. Im dead sure if I had your 8mbps connect, then a 450k+ rwin wouldnt be too shabby.

Mazakman · Post by **Mazakman** » Mon Jul 02, 2001 8:38 pm

Man, I am downloading great at the RWIN's that Lobo has suggested. Got 64 mb downloaded today in 3 minutes 43 seconds. Think that I am just about maxed out on this DSL line. LOL.

Idiot Savant · Post by **Idiot Savant** » Tue Jul 03, 2001 3:20 am

2.3Mbps.

Not too shabby, whats your cap?

Nm, just looked. You could get closer to your 3mbps cap by LOWERING that Rwin. Experiment some. A rwin of.. whatever 500k+ will let you D/l at speeds over 11mbps... and you cant run even 1/3 that value (being that youre capped at 3mbps). Lowering the Rwin will lower system load and possibly increase speed. Your machine is fast, so try MSS * 64 and scale that to whatever works best. (i.e. MSS * 64: *4, *6, *8)

Mazakman · Post by **Mazakman** » Tue Jul 03, 2001 8:46 pm

Hello Idiot Savant. I have been experimenting today with much lower RWIN's like you suggested and I am discovering that you are right. So far I have tested 93,440 ; 73,000 ; 75920 ; and 78,840. I am discovering much more even downloads. That 64 mb file that came in the other day in 3:43 downloaded in 3:41 at 73,000. My nubers at Speakeasy test site have been between 2411 and 2552 kbps . My numbers at PCPitstop on the 500 kb download test have been from 2597 to 2899 kbps. (clearing my cache each and every time ) . Would you suggest lowering my rcv window below my cap of 3000 ? Or do you think that I am in the ballpark now with these numbers.

Idiot Savant · Post by **Idiot Savant** » Wed Jul 04, 2001 4:15 am

Good Job

With these numbers you are closing in on your cap. You might wanna find the best value of the ones you chose and multiply that by 2 or 4 (for scaling). What will happen is if a server doesnt use scaling, it will use the unscaled value of your Rwin (in this case, obviously one you have had good results with), and if it does use scaling, it will allow a bit faster dl's. Here is a recommendation of mine, use if you like.

Rwin 210240
Unscaled Rwin of 52560 (MSS * 36) *4

Rwin 186880
Unscaled Rwin of 46720 (MSS * 32) *4

Rwin 146000
Unscaled Rwin of 73000 (MSS * 50) *2

Mazakman · Post by **Mazakman** » Wed Jul 04, 2001 9:58 pm

Just an update Idiot Savant. I am running an RWIN value right now of 148920. I have been playing around most of the day with different values and this is one that I am going to try for a while longer. Seems to be pretty good for me. I have had some good download speeds with it and good reports from all the test sites. Just thought that I would let you know. Appreciate your help !

Idiot Savant · Post by **Idiot Savant** » Thu Jul 05, 2001 4:35 am

no prob mang, glad to help.

gRoUnD_zEr0 · Post by **gRoUnD_zEr0** » Thu Jul 05, 2001 5:32 am

I use RWIN of 280320 as you suggested..Works good with my cable, get better results at test sites than with higher RWINS. Thanks Mang