Slow speeds

Jolsa

Or should I just buy a laptop? lol!

Toxteth_OGrady

Good info on MTU and RWIN tweaking here

But i still don't think that's your problem. If flatmate 2 has a Win pc can you try a fileshare test on that?

:cool:

TOG

albertross_2

1500 sounds high, but you need to set it at that to do tests, in order to find out what your maxmtu is.

It will actually slow down the PC if it is too high, as well as too low.

You can test your optimum mtu with this.. set it to 1500, do the test, then change the mtu to the maximum unfragmented packet size +28. Mine is 1430/ 1458.

http://www.speedguide.net/downloads.php

or you can do a

ping -f -l 1500 https://www.google.com
ping -f -l 1499 https://www.google.com
ping -f -l 1498 https://www.google.com

etc until you get an unfragmented ping, then add 28 and set your MTU to that.

for example on mine a ping value of 1430 works fine, but 1431 says packet needs to be fragmented. Hence 1430 is good, add 28 to get 1458 at MAXMTU.

Jolsa

Yeah I'll have a bash at that tomorrow, not looking forward to it though (previous attempts have left the monitor plotting a trajectory towards the window) ;-)

On a lighter note, I've just put 2 and 2 together and realised the link between your name and your picture :-) Thought it was their landlord at first, but then the University challenge episode came in to my head - giant eclairs and all lol!

Toxteth_OGrady

kewl

btw - can you connect directly to your router with an ethernet patch cable, disable your wireless and then do a speed test?

:cool:

TOG

Jolsa

TOG - cant connect direct, dont have a cable long enough.

albertross - dont understand the ping -f -l 1500 text on google - what am I meant to be doing here? I assume the TCP Optimizer found via your first link will do the necessary though?

Another thought, if I've previously had high download speeds (only a few weeks back I recall getting some 300 KB/Sec with the download of the same file, although I accept this is a rarity) then would the problem be with my wireless card? i.e. if the wireless card has shown to 'accept' high download rates in the past, then does that prove that the wireless card isnt limiting my download rate and therefore isnt the problem?

Could it be anything to do with the ports the information is being transmitted on, or a firewall issue? (sorry if that's nonsense, but I'm only thinking that maybe my flatmates laptops are set up better in some way?)

Toxteth_OGrady

A cable connection would bowl out whether or not it's your wireless card. Cheaper to buy a cable than a new wirless card on speculation. Can you not take the mountain to Mohammed and move you pc closer just for the test?

The piing command that albertross suggested is a way of finding the maximum packet size you can send before the data needs to be broken up. One of the optimizers has a menu selection to do the same thing - cant remember whether it's TCP Optimizer or Dr TCP.

:cool:

TOG

Jolsa

Interesting, used the utility albertross mentioned to find my max MTU (it said I can use 1500), and applied the changes.

Downloading the file now, it immediately comes up with approximately 370 KB/Sec, then 280 KB/Sec, then 180 KB/Sec before hovering around 120, 115 and 110 KB/ Sec - a level which it seems quite happy at i.e. no more dramatic variation of the download rate.

So what does that mean?!

Toxteth_OGrady

what's the adslguide speedtest giving after your tweak?

:cool:

TOG

albertross_2

I'm surprised it suggests setting it at 1500, have you run the largest MTU test in TCP opt. (you always have to add 28 to the largest unfragmented packet size to get the MAXMTU)

Mine reports this:

The largest possible non-fragmented packet is 1430 (1458 - 28 ICMP & IP headers).
You can set your MTU to 1458

if you go to dos (Start run cmd), and do ping -f -l 1500 https://www.google.com, it would mention fragmentation if your maxmtu is too high.