From: Goswin von Brederlow <goswin-v-b@web.de>
To: Miklos Szeredi <miklos@szeredi.hu>
Cc: goswin-v-b@web.de, linux-kernel@vger.kernel.org
Subject: Re: include/linux/aio_abi.h and IOCB_CMD_POLL
References: <87d49k6h45.fsf@frosties.localdomain>
	<E1MCCnb-0005Bc-09@pomaz-ex.szeredi.hu>
Date: Thu, 04 Jun 2009 17:18:24 +0200
In-Reply-To: <E1MCCnb-0005Bc-09@pomaz-ex.szeredi.hu> (Miklos Szeredi's message
	of "Thu, 04 Jun 2009 15:16:03 +0200")
Message-ID: <87hbyw6n9b.fsf@frosties.localdomain>
User-Agent: Gnus/5.110006 (No Gnus v0.6) XEmacs/21.4.22 (linux)
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Sender: linux-kernel-owner@vger.kernel.org
Content-Length: 1221
Lines: 35

Miklos Szeredi <miklos@szeredi.hu> writes:

> On Thu, 04 Jun 2009, Goswin von Brederlow wrote:
>> 3) Are there any alternatives to libaio that don't use threads and
>>    support polling?
>
> There are the poll, select and epoll interfaces that block, but are
> able to multiplex events from many file descriptors.

Unfortunately libaio does not use an fd to pass events between user
and kernel space so one can't use poll, select or epoll to wait for
/dev/fuse or libaio to have some work pending. And none of them
replace libaio functionality in respect to read/write.

And alternating between io_getevents and e.g. select with a tiny
timeout seems like a verry bad idea efficiency wise.

> And there's the O_ASYNC flag that can be set with an fcntl(), that
> sends a SIGIO signal on an I/O event.

This might work together with libaio. Never used SIGIO though but I
will try. Thanks for the idea.

> All of these work on /dev/fuse.
>
> Thanks,
> Miklos

MfG
        Goswin
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/