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[Helpneedadvice]

>> He was seeing a different (higher) "pull" from his end than I was seeing.

Sorry, I dont know what he meant by that.

Well, he got me to download a file and the speed I saw whilst downloading was around 450kB/s, whereas he was monitoring his end and saw 500kB/s. Then he got me to download a second file at the same time which for me was around 70 kB/s. The total he monitored his end for the two files was greater than I was seeing my end (he was seeing me hit 6000kbps but fluctuating somewhat), hence his conclusion.

He went away and tested my line from his end and called back and confirmed that it was a BT contention issue.

[kitz]

>> saw whilst downloading was around 450kB/s,

Thats 3600 kbps.. and whilst not great and slow for an 8Mbps thats within acceptable contention parameters..  when/what time was that?

Are you still seeing the very low speeds?

The difference between 450 KB/Sec and 500 KB/Sec could very well be things like TCP/IP/ATM overheads.  Without a doubt he will be seeing the overheads - you may just be seeing the throughput speed http://www.kitz.co.uk/adsl/speeds2.htm
The difference between those 2 figures seem about right for overheads... 
The reason why our routers will say sync at 8128 yet the maximum throughput speed we will ever see is around 7Mbps is because of overheads.

[Helpneedadvice]

That was around 4pm. However, at other "quiet" times of day eg 6:30 am, I've been getting as low as 1.9M and then evenings, I can get 6M, all on 6500 profile...just seems bizarre that the slower speeds are happening at the quieter times and vice versa. I would understand it if it was the other way around.

Thanks for explaining the overheads

Is it worth me tweaking those settings you mentioned before Kitz?

I guess otherwise I must just wait and see if BT's fix changes anything.
I'm gonna get a reprofile in the next few days anyway since the noise on my line from BT reconnecting the bellwires mucked it up before. Should get a better Fault threshold out of them at least and hopefully SNRM will decrease as instability has largely gone now. Maybe I will get some better speeds from that.

[kitz]

>> I've been getting as low as 1.9M and then evenings, I can get 6M,

Ahh.. thats an improvement than the other week? Now we are into the the realms of contention speeds - whether it be ISP or exchange I dont know...  But what is weird is that it is "the wrong way round".
 
Wonder if a pile of users who get free off peak usage that doesnt count towards the monthly allowance are on your exchange/ISP. ?

Tweaking certainly wont harm.  Try the settings shown in the image .  Select your speed from the drop down menu.
Hake also brought up an interesting topic about Window Scaling, TimeStamping  and contention/congestion in this thread.   Ive not noticed TimeStamping making any difference on my own line.. but then again Im not seeing any contention right now.  So worth a try.

[Helpneedadvice]

Well I have "tweaked". To be honest, I'm not sure how to tell if it made any difference as my throughput is so variable, but hey whatever I can do to maximise it is great Thanks Kitz!

The tweak tester program said I wasn't pingable - does that matter in my case?

I noticed my timestamping is off anyway and black hole is set to yes rather than default as per the image. Does that matter?

Window scaling said it was set to 2.

[Helpneedadvice]

Ah OK just read the link - it's recommended to try it switched on, right?

[Helpneedadvice]

OK just did that T/S now switched on - well speedtests this morning were good, will see how they vary throughout the next few days.

My MTU figure was previously blank and my top receive window figure was 450120 now set to 204192. Does that mean it was a long way out from ideal before?

The adapter setting keeps resorting to "1394 Net adapter"when I go back in even though I save it as "Ethernet controller" for my router.

[Helpneedadvice]

Ooh interesting, I just tried to download the same file that the ISP asked me to do yesterday to look at the speed and not only was the speed up at 776 kB/s (6249kbps)(as opposed to the 450 kB that i saw yesterday) - OK this could just be doing it's usual varying as it does throughout the day, but it is normally much worse in the mornings -  BUT VERY VERY NOTICEABLE was the fact that the download speed settled down quickly to a constant value and wasn't jumping around all over the place as it usually does whatever the time of day and the throughput. I will test it again later and see if it is still the same.

Am I right? Would the tweaking have this stabilising effect? The ISP yesterday also noticed the jumping around from his end of things.

[Helpneedadvice]

Eric - side issue again : do the companies like 123-reg give you plenty of advance warning when your registration is about to expire? (ie what if you're on holiday!) Thanks

[roseway]

123-reg send you an email giving 60 days notice of the expiry of your domain, but it probably makes good sense to keep your own reminder anyway.

I'm not ignoring your questions about MTU by the way, but as I don't use Windows I know very little about the subject.

[Helpneedadvice]

Thanks eric I am definitely going to sort out my own domain.

It does seem that my download speed has signidficantly stabilised as a result of the tweaking.
Does anyone have any ideas about the questions that I posted above. i'd be grateful for input - thanks

[kitz]

>>> The adapter setting keeps resorting to "1394 Net adapter"when I go back in even though I save it as "Ethernet controller" for my router.

I think thats just the way DrTCP lists the order in the drop down box.  As long as you have selected the correct adapter and applied the MTU to that, then its ok.

>> my top receive window figure was 450120 now set to 204192.

What MTU value are you using?


>> BUT VERY VERY NOTICEABLE was the fact that the download speed settled down quickly to a constant value and wasn't jumping around all over the place as it usually does whatever the time of day and the throughput. I will test it again later and see if it is still the same.

Yes please do, this could be one of the effects of enabling TimeStamping that Hake and I were discussing in that other thread... and how it's said it may be beneficial on congested lines.  Its a bit of a suck it and see area though..  and since neither I nor hake are experiencing congestion, we havent been able to see any benefit, so were not sure if it does work or not.

MTU tweaking is and can be a bit of a grey area, in that some tweaks work better on some lines than others.

[Helpneedadvice]

>> my top receive window figure was 450120 now set to 204192.

What MTU value are you using?

1458 (was previously blank)

>> BUT VERY VERY NOTICEABLE was the fact that the download speed settled down quickly to a constant value and wasn't jumping around all over the place as it usually does whatever the time of day and the throughput. I will test it again later and see if it is still the same.

Yes please do, this could be one of the effects of enabling TimeStamping that Hake and I were discussing in that other thread... and how it's said it may be beneficial on congested lines.  Its a bit of a suck it and see area though..  and since neither I nor hake are experiencing congestion, we havent been able to see any benefit, so were not sure if it does work or not.

MTU tweaking is and can be a bit of a grey area, in that some tweaks work better on some lines than others.

It does seem to be consistently more settled and the download speed does indeed seem to be higher. Lowest I've got since changing the MTU and T/S settings has been 650kB/s versus the 450kB/s i was getting when my ISP asked me to try downloading that file a couple of days ago. Can't say whether it was due to the T/S or the new MTU settings though.   

[Helpneedadvice]

Can't say whether it was due to the T/S or the new MTU settings though.  

Meaning - I think one of these settings has helped but not sure which one!

[kitz]

>> 1458 (was previously blank)

Ah thanks - RWIN of 204192 is for lines syncing at full 8Mb, since youre getting more like 6Mb speeds then 153144 should work well too.

>> Meaning - I think one of these settings has helped but not sure which one!

If its now working much better - which it seems to be - as there's quite an improvement..  then leave alone