Cable Forum - View Single Post - Cable slowed to a crawl at peak times, like clockwork

Sephiroth · 29-01-2010, 13:20

Thanks. When you do it again tonight, please use PATHPING rather tham Tracert.

Anyway, it looks like the second of my diagnosis points would apply. To be confirmed this evening. I suspect there's a circuit problem that kicks in during peak load times. I'll explain.

There are a very large number of packets arriving at the cable modem with errors that are correctable by the Reed-Solomon mechanism.

Correctable
Codewords 3598807 765477 173223102 N/A
Uncorrectable
Codewords 284 297 294 N/A

Some of these are uncorrectable. It may be that this has given rise to the T6 message which means that the CM has not been able to register and is restarting the registration process.

Other than that, you SNR and other modem stats are fine.

The T3 errors occur at non-peak times as well. The wisdom is that noise on the upstream channel is the cause of T3 timeouts. It will be worse at peak times when there is contention for a time slot on the upstream channel.

Without more ado (but it would be instructive to see your later figures), you could post your modem stats and event log on the support newsgroup. They'll check your circuit and post back their informed opinion as to what's going on. Point out to them the T3 timeouts and the Correctable Codewords.

If you're on Vista or Windows 7, you would use Windows Live Mail (a standard part of your system). To get on the VM Newsgroup you need to be operating through the VM broadband system.

In Windows Live Mail, you'd click the "Newsgroups" link at the bottom of the screen and then Tools/Accounts then Add/Newsgroup Account.

Give your Display Name (like rsdx), your e-mail address (optional or you can make one up!) then your server address for the newsgroup which is "news.virginmedia.com".

You'll then be able (via the Newsgroups menu item) to select the Virgin media icon on the left of a search panel, click on "All" and wait a few minutes till it's finished listing thousands of newsgroups.

Scroll down to "Virginmedia.support.broadband.cable" and double click it.

And you're there. You can post your stuff including any evidence you've collected.

HTH.

PS EDIT: Now you're forked between Broadbandking's advice and mine!

29-01-2010, 13:20	#5
Sephiroth Wisdom & truth Join Date: Jul 2009 Location: RG41 Services: RG41: 1Gig VOLT Rutland: Gigaclear 400/400 Posts: 12,725	Re: Cable slowed to a crawl at peak times, like clockwork Thanks. When you do it again tonight, please use PATHPING rather tham Tracert. Anyway, it looks like the second of my diagnosis points would apply. To be confirmed this evening. I suspect there's a circuit problem that kicks in during peak load times. I'll explain. There are a very large number of packets arriving at the cable modem with errors that are correctable by the Reed-Solomon mechanism. Correctable Codewords 3598807 765477 173223102 N/A Uncorrectable Codewords 284 297 294 N/A Some of these are uncorrectable. It may be that this has given rise to the T6 message which means that the CM has not been able to register and is restarting the registration process. Other than that, you SNR and other modem stats are fine. The T3 errors occur at non-peak times as well. The wisdom is that noise on the upstream channel is the cause of T3 timeouts. It will be worse at peak times when there is contention for a time slot on the upstream channel. Without more ado (but it would be instructive to see your later figures), you could post your modem stats and event log on the support newsgroup. They'll check your circuit and post back their informed opinion as to what's going on. Point out to them the T3 timeouts and the Correctable Codewords. If you're on Vista or Windows 7, you would use Windows Live Mail (a standard part of your system). To get on the VM Newsgroup you need to be operating through the VM broadband system. In Windows Live Mail, you'd click the "Newsgroups" link at the bottom of the screen and then Tools/Accounts then Add/Newsgroup Account. Give your Display Name (like rsdx), your e-mail address (optional or you can make one up!) then your server address for the newsgroup which is "news.virginmedia.com". You'll then be able (via the Newsgroups menu item) to select the Virgin media icon on the left of a search panel, click on "All" and wait a few minutes till it's finished listing thousands of newsgroups. Scroll down to "Virginmedia.support.broadband.cable" and double click it. And you're there. You can post your stuff including any evidence you've collected. HTH. PS EDIT: Now you're forked between Broadbandking's advice and mine! __________________ *Seph.* My advice is at your risk.