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From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH] tcp: SO_TIMESTAMP implementation for TCP
Date: Fri, 30 Apr 2010 16:41:15 -0700 (PDT)
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From: Tom Herbert <therbert@google.com>
Date: Fri, 30 Apr 2010 00:58:32 -0700

>> All these new checks and branches for a feature of questionable value.
> 
>> If you can modify you apps to grab this information you can also probe
>> for the information using external probing tools.
>>
> I don't see an nice way to do that, we're profiling a significant
> percentage of millions of connections over thousands of paths as part
> of standard operations while incurring negligible overhead.  The app
> can can easily timestamp its operations, but without some mechanism
> for getting timestamps out of a TCP connection, the networking portion
> of servicing requests is pretty much a black box in that.

If other people have an opinion about this, now would be the time
to speak up. :-)