1.24 - Max Connections not working

[almondega1]

Hi folks.

Since version 1.23 I'm having difficulties to download torrents regarding the number of half-connections/connections BitComet is doing.

In the advanced options of BitComet, I set network.max_connecting_connections to 100 and network.max_connections to 100 either.

Now, after a task is started and after a while, my connection drops.

The connection with the ISP is still active, but I'm not able to browse any website and the task download/upload goes to 0/0.

After a few moments, lets say 20 seconds, the task start downloading/uploading again and I'm able to also navigate the internet.

So, I went to look the Comodo Firewall, to see what is going on with my connection, and for my surprise, there are thousands of BitComet connections, inbound and outbound.

If I set the limit to 100, as least theses numbers shouldn't be around thousands.

Attached are the screenshots showing the total of connections in my Windows, and the advanced configuration of BitComet.

Note that, closing BitComet, the total connection drops to 3... maybe 4, so yes, these thousands connections are from BitComet (even looking at the connection list there are lots of bitcomet tcp/udp connections).

Also I saw that around 1800 connections (usually starting a new task goes to this ammount of connections) causes the "internet" drop, the problem I said before.

This number then start droping, and around 1000 the task start downloading again and I'm able to use the internet.

In windows XP we had the tcp limit, but I'm using Windows 7 now, and there is no half tcp/limit anymore, at least I found websites saying that and didn't find any software to change this number.

Also, my router is right configured to forward bitcomet connections to my computer.

The question is: why the number of bitcomet connections are too high, if I set to a lower number.

Question reason? this mess up my connection, I lost connection with my games, msn, gtalk and not able to open websites.

Thanks.

Edited November 15, 2010 by almondega1 (see edit history)

[Vasy]

You allow 100 connections to be started every second and then you ask yourself why so many are started? :huh:

While I had windows XP, I had the limit set to 8. I had no problems reaching my connection's maximum bandwidth.

Now I have windows 7 32bit, the limit is set to 0(automatic) and I see speeds above 10mB/s (up/down) quite often.

Bottom line? It has no effect on your speed.

Windows vista sp1 (I think) and above don't have the maximum connections/second limit and have a dynamic way of handling that limit. Messing with that limit in windows 7 is a very bad idea.

Give it a try, set it to 0, let it run for a while and see if you encounter any problems.

[almondega1]

Hi Vasy, thanks for reply.

I didn't know that number was connections per second.. I set it to 0 (automatic) and the problem continued.

Also.. I set to 10, then the download speed was very slow and the problem of "connection lost" continued.

Also.. starting bitcomet, without download anything, fires up 2000+ connections (don't know why, I have long time seed disabled).

So.. now i'm testing uTorrent, with max connected peers set to 100 (configured in utorrent) and 300 connections are displayed in Comodo Firewall.

I'm downloading at full speed and able to play a game without getting disconnected by tcp lost.

I really like bitcomet, and maybe i'm missing some configuration..

Any tips?

Thanks.

[greywizard]

The network.max_connections parameter acts on and limits the number of TCP connections, that the client can have opened at any time.

However, if you'll look in Comodo at the connections page, you'll see that more than 80% of the "connections" are on UDP protocol (which is being used mainly by DHT). UDP is a connectionless protocol, therefore this doesn't place such a big stress on your PC as it would if these were TCP connections. However, your software firewall and your router will often regard any pair of sockets communicating, as a "connection" regardless if it's using TCP or UDP as a transport protocol.

That's because, sockets that communicate occupy entries in the internal tables of those respective entities (e.g. in the NAT table of the router). For some router models this can probably lead to exhausting the memory allocated to the NAT table and to issues of this type.

I've requested too, a while ago an option to limit the max number of simultaneous UDP transmissions incoming and outgoing, just to be able to troubleshoot this type of issue, but I'm not sure how easy it is to implement for the team.

[almondega1]

Indeed grey, this could be a router exhaustion problem.

I tried disable the DHT, but the number of connections continued high.

I'll be waiting for an update to cap UDP connection limit.

Thanks.

[kluelos]

One way to tie it down to the router is to borrow someone else's temporarily, and see if the problem goes away when you hook up a different router.

Make sure you have the latest firmware upgrade for it. Check for third-party upgrades also. If it is the router and you can't find a solution, you may want to simply buy another. In this area, I have observed that you do not get what you pay for, and that cheap routers (street price about US$20) work as well as much more expensive ones, so look for local sales. Otherwise, you may want to see if you can simply swap with someone else. The router's just fine if you don't use P2P software, and a lot of people do not, so you might be able to find one of them to swap routers with.