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Date: Wed, 30 Jan 2002 12:07:17 -0600
From: Corey Minyard <minyard@acm.org>
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To: Zwane Mwaikambo <zwane@linux.realnet.co.sz>
CC: "Richard B. Johnson" <root@chaos.analogic.com>,
        Linux kernel <linux-kernel@vger.kernel.org>
Subject: Re: TCP/IP Speed
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Zwane Mwaikambo wrote:

>On Wed, 30 Jan 2002, Richard B. Johnson wrote:
>
>>But it's already connected.
>>
>>
>>         host:
>>         for (;;) {
>>            gettimeofday(...);
>>            write(s, buf, 64);
>>            read(s, buf, sizeof(buffer));
>>            gettimeofday(...);
>>         /* delay is 1.0 ms */
>>         }
>>         server is IPPORT_ECHO
>>
>
>You didn't make that explicit in your previous email, and anyway what kind 
>of resolution can you expect from gettimeofday...
>
Depending on the processor, gettimeofday has very high resolution.

If I remember correctly, the TCP stacks put in delays for small sends so 
they can pack multiple things together.  I think there are ways to work 
around this via some type of flush, but memory fails me on exactly how.

-Corey

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