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Date: Thu, 24 Jul 2008 13:18:13 +0200
From: Gerd Hoffmann <kraxel@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH 2/3] Always
	use	nonblocking	mode	for	qemu_chr_open_fd.
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To: qemu-devel@nongnu.org

Samuel Thibault wrote:
> Jamie Lokier, le Thu 24 Jul 2008 10:24:03 +0100, a =E9crit :
>> Gerd Hoffmann wrote:
>>>   (2) Run ptys in non-blocking mode.  Drawback: we risk loosing data
>>>       in case the pty reader is slow (also when nobody is connected o=
f
>>>       course, but that is intentional ...).
>> (4) Run ptys in non-blocking mode, but use a small output buffer in
>>     QEMU so nothing is lost.  It's not that hard.
>=20
> Err, there's _already_ a small buffer in the kernel pty layer :)

Yep, one page (aka 4k on x86) in size.  Of course we can buffer in qemu
too.  That doesn't solve the fundamental issue though (unless we don't
limit the buffer size, which would be insane IMHO).

cheers,
  Gerd

--=20
http://kraxel.fedorapeople.org/xenner/