BitTorrent broken in 2.5.2.0?

[grey-hame]

I started a download of a 1GB torrent with a couple of thousand sources and the following symptoms immediately presented themselves:

[ul][li]The torrent downloads slowly, at around 20KB/s, and uploads even more slowly, ranging from 0 to 5KB/s, on my broadband connection.[/li]
[li]Applications like email do not work at all, reporting connection timeouts.[/li]
[li]The web browser works but is sluggish. Pages don't start loading immediately but wait several seconds. Sometimes they load only partially, or don't have the normal appearance, as if being displayed in an old Mosaic style browser instead of a modern one. Sometimes they fail, but not with timeout errors; HTTP connections instead seem to be subject to bogus RST packets being interjected into the stream somehow, somewhere. HTTPS times out but not quite 100% of the time.[/li][/ul]

This should not be happening, as near as I can tell. I pass the connection test and the total activity from Shareaza is nowhere close to saturating either my down or my up-pipe so it should not be affecting other applications at all. The last time I downloaded a torrent was, I think, a few months ago with 2.5.1.0 and the same hardware, ISP, etc., and this problem did not occur. I conclude that it is new in 2.5.2.0.

What gives?

[grey-hame]

Installed 2.5.3.0. Torrent throughput is now normal, but the effects on other applications are unchanged. It's using about 2/3 of my down-pipe and 1/4 of my up-pipe, still not enough to explain the impact on other applications.

Looks like the symptoms I described in my first post to this thread were the result of 2 bugs, one (and only one) of which got fixed in 2.5.3.0.

[cyko_01]

[grey-hame]

[old_death]

[grey-hame]

[cyko_01]

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[cyko_01]

[siavoshkc]

[grey-hame]

[old_death]

[ailurophobe]

The symptoms sound like you are hitting the half-open TCP connection limit. Are you on XP?
I suppose a firewall, NAT, or anti-virus network shield could cause this as well.

[grey-hame]

Connection limit bumped to 500.

Firewall told to allow Shareaza's traffic, inbound and outbound.

NAT port-forwarded.

Antivirus checks newly-altered files on disk, and specific network activity (email), but shouldn't bother Shareaza. It's specifically been told to ignore Shareaza's incomplete directory (but not its download directory, so when completed files are moved there they get scanned).

[ailurophobe]

You might be hitting the connection limit on your router, or your ISP might enforce some sort of a connection cap to prevent P2P from spending all the bandwidth. I think it's used on cable, student housing, and other networks where many users share the same uplink. DSL and fiber are more robust in this respect. ISP limit could have been set without you knowing about it, so it would fit your story. Perhaps your BitTorrent client connections is too high?

[kevogod]

[grey-hame]

That would have prevented the specific instance, but why have a limit at all? And why not enforce the limit by automatically ignoring the deeper quoted elements rather than getting mad at the user?

As for connection limits, why would the torrent download at full speed while only everything else got affected by it?

[ailurophobe]

The reason for the quote limit is because the quotes are indented and each level of nesting results in more wasted space on the left side of the page. Deeply nested quotes are a nuisance to people with low screen resolutions. And even if your display can handle it, it becomes progressively harder to keep track of whose text you are reading when the nesting level increases. Human mind can easily distinguish your text, a quote inside your text, and a quote inside the quote from each other, but keeping track of how many levels of quotes you are inside requires conscious thought and reduces readability. When something makes forums implemented with your software look like crap and be hard to read... You already know what the developers of phpbb did about that.

P2P is designed to handle failures to connect to a peer gracefully. Chunks it would have downloaded from the source it failed to connect are simple downloaded from another source it already has a connection to or connects to later.If a web browser fails to connect it has to try again until it succeeds, it does not have an alternative source it can try. Also making new connections is only a problem when starting a new download (BT) or accessing a new site (browser). Changing sites is not just more frequent it is something that happens with the user watching and waiting for it.

[kevogod]

[grey-hame]

[ailurophobe]

Automatically altering your post without bothering to inform you? I once witnessed a mod doing it for a much better reason, still remember it years later because of the long and pointless argument that followed. And unfortunately indenting is the only attribute commonly known that works for even three or four steps. Even for the color blind. And is understandable without reading a manual the first time you see it. And visually shows the structure of the past discussion. As for leaving it to the user... Most people, no matter how smart and well-informed otherwise, don't even know about the issue, let alone understand it, and the ones that do avoid doing even three deep quotes because that is already a pain to read for others. Typography and legibility just are not issues most people ever think about. Anyway, I only wrote about this because it seemed you did not understand why there is a hard limit and I happened to understand some of the reasons. Just let it go. Not like it is a big problem or as if anyone here could actually do anything about it, or were in anyway responsible for it being that way.

As for the actual topic: BT (and G2) connections are persistent. Once Shareaza has connected to the sources it needs, it makes no real performance difference how difficult connecting to more sources would be as far as the protocol is concerned. The application still might have problems since the connection attempts require resources that are then not available for anything useful.

Anyway, if it is a connection limit issue then reducing downloads.maxtransfers and/or bittorrent.downloadsconnections will make it go away and trying to connect as a hub will make it worse. It is easier to just try it out than to discuss it. (Not like we have enough info to get any results without experiments anyway.)

[kevogod]

[ailurophobe]

The discussion (on my part) was whether it is reasonable and correct to have a hard limit by default. You already told before that the limit can be changed and I assume even removed (at least with a mod), but that changes neither the default behaviour nor the reasons it exists that make removing it impractical. But you are right, what I actually wrote does (even in context) strongly suggest something that is entirely incorrect. My bad and thanks for the correction.

[grey-hame]

[old_death]

[ailurophobe]

[cyko_01]

[grey-hame]

[ailurophobe]

[grey-hame]

[ailurophobe]

What upload slots are you talking about? The only upload slots I know of are the ones for the HTTP and ED2K queues none of which have any relation to BitTorrent. What BitTorrent uses are client connections which it uses to both download, upload, and simply to connect to the rest of the swarm. There are no separate download and upload connections. Just client connections that are used for either or both as the available bandwidth allows.

Well, if you don't have any torrents going, I guess there is no real urgency. You only have problems when using torrents, right?