All of a sudden tonight my web browsing and ssh performance is terrible. I''m on a cable connection and I''m wondering if it could be due to evening bandwidth contention or ISP throttling. If so, I suppose tcdevices numbers are out the window. Can anything be done? - Grant ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword
Grant wrote:> All of a sudden tonight my web browsing and ssh performance is > terrible. I''m on a cable connection and I''m wondering if it could be > due to evening bandwidth contention or ISP throttling. If so, I > suppose tcdevices numbers are out the window. Can anything be done?Grant, You are proving to be too high-maintenance for my bandwidth. I''m cutting you loose. ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword
Grant wrote:>All of a sudden tonight my web browsing and ssh performance is >terrible. I''m on a cable connection and I''m wondering if it could be >due to evening bandwidth contention or ISP throttling. If so, I >suppose tcdevices numbers are out the window. Can anything be done?First thing you can do is look at your TC numbers and see where the packets are queuing up - if your TC isn''t throttling it, then it must be external. As I wrote in another thread ("Traffic Shaping Newbie", 20th Jan), unless you have a guaranteed minimum bandwidth then you have to compromise. If you configure your TC when there is no contention (in the local cable network, or in the ISPs backhaul) then it will fail to function once contention kicks in and your available bandwidth drops. All you can do is compromise : Reduce your inbound and outbound rates to allow for the contention. The downside is that unless you throttle yourself down to the worst case situation, then you are still going to have periods where your tc doesn''t work properly. And any reduction in rates you specify will restrict you for the other 22 hours of the day. Over here in the UK, ADSL used to be sold on contention ratio but virtually all ISPs have dropped that and no longer mention it. Typical for home use was 50:1, so a 2Mbps ADSL service could cut you down to just 41kbps ! Not many people realise this, and I think the best way to deal with some of the complaints would be to force the ISPs to quote minimum rates (aka CIR, Committed Information Rate) which is common in business environments - but that''s another thread ! So if you had such a 50:1 2M service, to guarantee effectiveness of your tc, you would need to set your inbound rate to just under 41kbps. In the real world, the other 49 won''t be using there 2M all the time - that''s why the ISPs can (or at least could) get away with it. Now torrenting and watching video is so common, more people are using more bandwidth for more of the time and congestion in the backhaul (or local segment in cable networks) is more of a problem. -- Simon Hobson Visit http://www.magpiesnestpublishing.co.uk/ for books by acclaimed author Gladys Hobson. Novels - poetry - short stories - ideal as Christmas stocking fillers. Some available as e-books. ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword
>>All of a sudden tonight my web browsing and ssh performance is >>terrible. I''m on a cable connection and I''m wondering if it could be >>due to evening bandwidth contention or ISP throttling. If so, I >>suppose tcdevices numbers are out the window. Can anything be done? > > First thing you can do is look at your TC numbers and see where the > packets are queuing up - if your TC isn''t throttling it, then it must > be external. > > As I wrote in another thread ("Traffic Shaping Newbie", 20th Jan), > unless you have a guaranteed minimum bandwidth then you have to > compromise. If you configure your TC when there is no contention (in > the local cable network, or in the ISPs backhaul) then it will fail > to function once contention kicks in and your available bandwidth > drops. All you can do is compromise : > > Reduce your inbound and outbound rates to allow for the contention. > > The downside is that unless you throttle yourself down to the worst > case situation, then you are still going to have periods where your > tc doesn''t work properly. And any reduction in rates you specify will > restrict you for the other 22 hours of the day. > > Over here in the UK, ADSL used to be sold on contention ratio but > virtually all ISPs have dropped that and no longer mention it. > Typical for home use was 50:1, so a 2Mbps ADSL service could cut you > down to just 41kbps ! Not many people realise this, and I think the > best way to deal with some of the complaints would be to force the > ISPs to quote minimum rates (aka CIR, Committed Information Rate) > which is common in business environments - but that''s another thread ! > > So if you had such a 50:1 2M service, to guarantee effectiveness of > your tc, you would need to set your inbound rate to just under 41kbps. > > In the real world, the other 49 won''t be using there 2M all the time > - that''s why the ISPs can (or at least could) get away with it. Now > torrenting and watching video is so common, more people are using > more bandwidth for more of the time and congestion in the backhaul > (or local segment in cable networks) is more of a problem.Thank you for taking the time to explain. That''s what I was afraid of. How can I look at my TC numbers and see where the packets are queuing up? Is that done in tcdump? - Grant ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword
Grant wrote:> Thank you for taking the time to explain. That''s what I was afraid > of. How can I look at my TC numbers and see where the packets are > queuing up? Is that done in tcdump?shorewall show tc Again, this is spelled out in the Shorewall Traffic Shaping doc. ------------------------------------------------------------------------------ This SF.net email is sponsored by: SourcForge Community SourceForge wants to tell your story. http://p.sf.net/sfu/sf-spreadtheword