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Date: Tue, 3 Nov 2009 10:24:58 +0530
From: Amit Shah <amit.shah@redhat.com>
Subject: Re: [Qemu-devel] [PATCH] char: tcp: increase size of buffer that
	holds data to be sent out
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: qemu-devel@nongnu.org

On (Mon) Nov 02 2009 [10:52:02], Anthony Liguori wrote:
> Amit Shah wrote:
>> 1k is too less; at least send out 4k of data from a chardev.
>>   
>
> Why is 1k too small?

Definitely depends on the apps that pump in the data. If an app has data
to pump, it will keep pumping as much data as possible (eg, Linux
syscalls issue read / write requests for 32k bytes of data).

The char devices have a 'can_read' call to determine how much the
backend can accept.

We're artificially limiting to 1k in this code, even if the app can pump
and the backend can receive, resulting in multiple splits.

In the case of virtio, 4k is available if the guest is able to receive
data.

		Amit