linux-kernel - Re: PROBLEM: Epoll frequently fails to notify connects at connect bursts

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Message-ID: <8a1bd2320908260215w23d1f426x33f90e38ccc3fe2c@mail.gmail.com>
Date:	Wed, 26 Aug 2009 11:15:10 +0200
From:	Will Brown <dr.hfuhruhurr@...il.com>
To:	Davide Libenzi <davidel@...ilserver.org>
Cc:	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
Subject: Re: PROBLEM: Epoll frequently fails to notify connects at connect 
	bursts

On Wed, Aug 26, 2009 at 3:24 AM, Davide Libenzi<davidel@...ilserver.org> wrote:
> On Tue, 25 Aug 2009, Davide Libenzi wrote:
>
>> Multiple quasi-simultaneous events for the same fd are merged. This is why
>> on POLLIN on accepting sockets you want to do something like:
>>
>>       while ((afd = accept(sfd, ...)) != -1)
>>               add_client(afd);
>
> Of course, with  sfd  in non-blocking mode. Alternatively, you drop EPOLLET
> for the  sfd  socket.
>

Aha! Thank you immensely Davide. It cost me one week of frustration already.

1. Where should I have picked up this gem of essential information? I
haven't seen it in the man-pages for either 'epoll' or 'accept'.

2. Is it better to use a level-triggered listener socket, or to use
the accept-loop?

Thanks a million,
Will
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