Thread going into endless loop once the TCP connection limit is reached

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Follup ticket from http://code.google.com/p/trinitycore/issues/detail?id=3707

This is a different issue as described in #15, but can be the result of the fd leak.

Once the file descriptor limit for TCP connections is reached one TC thread (most likely networking) starts looping and the server becomes almost inaccessible.

Hooking up strace to the looping thread showed the following:

{{{

strace -p 28226

epoll_wait(15, {{EPOLLIN, {u32=22, u64=22}}}, 1, 0) = 1
accept(22, 0, NULL) = -1 EMFILE (Too many open files)
epoll_ctl(15, EPOLL_CTL_MOD, 22, {EPOLLIN|EPOLLONESHOT, {u32=22, u64=22}}) = 0
epoll_wait(15, {{EPOLLIN, {u32=22, u64=22}}}, 1, 0) = 1
[.. endless spam with the same lines ..]
}}}

How it should work:

Once the limit is reached TC should simply discard the incoming connection until other connections get closed and free up resources below the limit.

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Author: marky81
I am having a lot this issue on rev: b28881f

Have a workround to fix this ? When its ocour TC is open but cant receive any new connections, i normaly restart all system :S

My ulimit -n is 65535

Tks

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Author: fureya
Confirm.

After server get 900+ online limit is reached even if server limit in config is 3k ;/

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Author: telsamat
i can confirm on 11080, bug still persists

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Author: signfinder
Dear leak - this bug http://www.trinitycore.org/t/trinitycore/ticket/689 is reproduced on servers with online 20, 300 and 900 players. ulimit -n 4096 is worth. In my opinion you're wasting closed that ticket

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Author: leak
Use strace -p PID on the thread that is consuming 100% CPU and we will know for sure.

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Author: snajl
confirm

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Author: leak
This issue is fully confirmed and already addressed.

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Author: maxdestroyer
trace -p 3446
Process 3446 attached - interrupt to quit
futex(0x450079e0, FUTEX_WAIT, 3574, NULL
seems like that is all

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Author: cyrex
Confirmed:

strace -p 2561
Process 2561 attached - interrupt to quit
futex(0x7f9a59bff9d0, FUTEX_WAIT, 2588, NULL

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Author: marky81
Yes really, any workaround ? Like a bash to check this and close tc2 ? this freeze is bad =/

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Author: telsamat
https://bitbucket.org/zippo/trinity_namiko/changeset/d0e207ac1587 i dont know it exactly but does it solve this problem?

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Author: derex
I have fix that is supposed to work on linux/unix -> https://github.com/derex/trinitycore/tree/handle_maxfd

I am now working also on working on windows version, because on windows the problem is actually caused by other stuff.

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Author: telsamat
thanks for that

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This issue is not completely closed, as it lacks some Windows-specific parts - do NOT close untill that is resolved.

[Voidx]

close?

[leak]

It took only 4 years and the removal of ACE to fix this issue.