Max half open TCP connections unable to set lower than 10

[ckyean23]

Hi,

I am using bitcomet 1.37 and I realise the advanced option of network.max_connecting_connections cannot be set below 10. So how to adjust it to 8 so as to allow smooth surfing?

My Tcp/ip limit is 10 as i am using windows XP and i do not want to patch it to a higher limit as this does not help in the download speed. So i am trying to change the max half open connection for BC (network.max_connecting_connections) from the auto value of 0 (default to 10 as seen on the Statistics Tab) to a value of 7 or 8 as recommended in this forum. But after i enter in 8 and click Apply, it always become 10. I have also tried 7 and 9 and same thing, jumps back to 10.

Is the lowest limit 10 for network.max_connecting_connections? If so, then how do i go about changing a lower value for it than the tcp/ip limit of 10?

Thanks in advance for any help.

[The UnUsual Suspect]

I see what you mean, I'm also unable to set a limit higher than 0 or less than 10 and I can ask the developers if this was intentional or a bug, however this limit never really was a problem and most of the info on the web about it was a result of a misunderstanding of what the limit does and the reasons for it.

If you're experiencing problems browsing while running torrents it's probably not this limit that is the cause. In most cases browsing problems are either bandwidth related or connections issues in your LAN (router), not your tcpip.sys.

How this limit works in Windows XP

When a program like Bitcomet requests to open a large number of TCP connections, windows will allow only 10 to initiate every cycle (approx per second), so in the first second you may open 10 and half of them complete instantly so 5 more are opened, The next second 10 more open, some complete allowing more to open and some remain half-open. A second later 10 more open and so on... usually within a min you can have a total of thousands of half open connections and the limit will no longer be reached. With this limit in place it is possible that you may have some sluggishness within the first minute or so when starting torrents, or if you stant a large number of torrents all at once, otherwise it shouldn't be a problem with browsing.

The reason patches were made to increase this limit was the false belief that you could only have a total of 10 half-open connections which isn't true, you can have many thousands of them, you just can't open more than ten at any one moment and this was a good thing when it was first imposed because many computers were being infected and used to send thousands of malicious connections every second and this slowed it down to a crawl. Current Windows versions still have this limit but it's been disabled because they have found better ways to prevent this type of attack.

In your case, what are the actual symptoms you're experiencing?

I suspect the advice you're attempting to follow is a bit outdated so I recommend you follow the first link in my signature and reply with all the requested info about your system and describe the symptoms of the problem you're experiencing and hopefully we can find a better way to address this, but I will inquire as to why there is no ability to set this value to less than 10.

[ckyean23]

First of all, thanks for the quick informative reply.

I never experienced any browsing problems at all and browsing was smooth while torrents are running. I reported this bug just because of another problem I suspect might be due to this bug.

The problem is sometimes, when a torrent is started, the LT seeds are not connected at all (no p2sp connected, only bt connected shown on the Peers Tab). And if this happens, I can right click on the torrent and select Update Tracker to connect to LT seeds. Sometimes need to update tracker a few times to connect to the LT seeds, but eventually I can connect no matter how. Just a matter of number of times of update tracker. However, sometimes I can also get them upon torrent first open. And since this problem is intermittent, I suspect the half open connection limit for Bitcomet might be the cause. Thus the posting here.

Can you explain to me the cause of my problem with LT seeds? As I hope to get the LT seeds always on torrent open and save the hassle of updating tracker sometimes when it fails.

[The UnUsual Suspect]

I'm not really sure about the issue with LTseeds that you report. We don't have any way to tell if there are LTseed resources available for a task and won't know until they are located and appear as peer connections. The technology behind LTseeds is independent of the bittorrent tracker so I don't see how updating the tracker would make any difference, but then again we really don't know what method is used for requesting LTseed peers, the only thing I do know is that they are gathered from BitComet's servers, not the torrent tracker but it's possible that the servers are contacted the same time the bittorrent trackers are reached, but I have no facts to base that theory on.

I did send an inquiry to development to ask why we are unable to use a setting below 10. I personally haven't used win XP in years so I don't have the same limit and have never changed from the default setting of 0 (automatic).

I will post if I find any additional info on this.

[ckyean23]

The LT seed feature, exclusive to Bitcomet, makes BC the most appealing and wonderful torrent client. Even old and dead torrents can revive. A creative concept from the BC development team I must admit.

From my observation, there is a way to check if there are lt seeds resources available for a torrent. Go to Files Tab and the column LT seeds will reflect the number of lt seeds for each file in the torrent. If I see all 0, I will need to update tracker and the number of seeds will be shown after one try or few tries. Then switch to Peers Tab and I can see my p2sp connected. peer to server peer. So I am pretty sure your assumption of connecting to BC server for lt seeds is done together with bt trackers is correct. Otherwise I won't see my lt seeds number in Files Tab ONCE I update tracker if I see all 0 at torrent start.

Do you think the max half open tcp connection of 10 for BC cause this lt seed problem? Because I cannot set a limit for BC lower than the OS limit.

[arigatokuzaimas]

ckyean23,

1. Hope it helps, have you try Bitcomet Tracker? it helps you to get more seeds, peers & download speed. Try Bitcomet Tracker & you dont have to update tracker again.

2. and in Advanved setting. i got no problem setting the network max connection connecting & network max connections network just leave it '0'.

for max half open for connections in utorrent can be set to 200 for best speed but your problem is different..

Edited March 19, 2014 by arigatokuzaimas (see edit history)

[The UnUsual Suspect]

The min number of half-open connections you can select will be changed to 8 in the next version of BitComet. For most users this won't matter, but for those who have the limit of 10 imposed on the operating system level this will help prevent BitComet from using all 10 of them which could be an issue if you start many tasks at the same time.

Thank you to the development team for agreeing to make this small change to help those members still using the older operating systems.

[The UnUsual Suspect]

To those who are following this topic, the min number of half-open connections was changed to 8 in version 1.38. For most users this is a pointless change, but for those using an OS that is limited to 10 connection attempts per second/cycle, setting this value to 8 will lessen the effect it may have on browsing when first starting a torrent. Once the torrent has been running for a few minutes it won't make any difference, but if you are in this minority you now have the option of selecting a value below 10.