Re: TCP perfomance

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There are quite a few things that make TCP performance degrade. Is there a
specific reason why you thought about TCP timestamps?
A good way to know is to launch a TCP connection and get it to a stage where
you can clearly see its performance suffer. Then first take a look at the
CPU usage... if its 100% only then you should conclude that the problem is
with the CPU usage aspect of it.
In my experience, there can be many other things that may go wrong. There
are quite a few 'TCP tuning' faqs around the Internet. You might want to go
through a few to see some commonly used solutions.

OTOH, TCP timestamps are an important part of TCP... may be not for a LAN
like system but definitely for a complicated network like the Internet,
where timestamps help TCP to easily infer round trip times with much more
precision than otherwise.

_r

On Fri, Jun 6, 2008 at 1:26 PM, Kevin Faulkner <[email protected]>
wrote:

> Miguel Sousa Filipe wrote:
>
>> There is no such thing has a TCP timestamp:
>> http://freebie.fatpipe.org/~mjb/Drawings/TCP_Header.png<http://freebie.fatpipe.org/%7Emjb/Drawings/TCP_Header.png>
>>
>> so, that doesn't make any sense...
>>
> Your right and I'm wrong.
> Its not in the header, its thrown on at the end....
> try doing
> cat /proc/sys/net/ipv4/tcp_timestamps
>
> http://www.networksorcery.com/enp/protocol/tcp/option008.htm
> http://www.securiteam.com/securitynews/5NP0C153PI.html
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> [email protected] mailing list
>
>

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There are quite a few things that make TCP performance degrade. Is there a specific reason why you thought about TCP timestamps?<br>A good way to know is to launch a TCP connection and get it to a stage where you can clearly see its performance suffer. Then first take a look at the CPU usage... if its 100% only then you should conclude that the problem is with the CPU usage aspect of it.<br>
In my experience, there can be many other things that may go wrong. There are quite a few &#39;TCP tuning&#39; faqs around the Internet. You might want to go through a few to see some commonly used solutions.<br><br>OTOH, TCP timestamps are an important part of TCP... may be not for a LAN like system but definitely for a complicated network like the Internet, where timestamps help TCP to easily infer round trip times with much more precision than otherwise.<br>
<br>_r<br><br><div class="gmail_quote">On Fri, Jun 6, 2008 at 1:26 PM, Kevin Faulkner &lt;<a href="mailto:[email protected]">[email protected]</a>&gt; wrote:<br><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
<div class="Ih2E3d">Miguel Sousa Filipe wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
There is no such thing has a TCP timestamp:<br>
<a href="http://freebie.fatpipe.org/%7Emjb/Drawings/TCP_Header.png" target="_blank">http://freebie.fatpipe.org/~mjb/Drawings/TCP_Header.png</a><br>
<br>
so, that doesn&#39;t make any sense...<br>
</blockquote></div>
Your right and I&#39;m wrong.<br>
Its not in the header, its thrown on at the end....<br>
try doing<br>
cat /proc/sys/net/ipv4/tcp_timestamps<br>
<br>
<a href="http://www.networksorcery.com/enp/protocol/tcp/option008.htm" target="_blank">http://www.networksorcery.com/enp/protocol/tcp/option008.htm</a><br>
<a href="http://www.securiteam.com/securitynews/5NP0C153PI.html" target="_blank">http://www.securiteam.com/securitynews/5NP0C153PI.html</a><br><font color="#888888">
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<a href="mailto:[email protected]" target="_blank">[email protected]</a> mailing list<br>
<br>
</div></div></blockquote></div><br>

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