Message-ID: <3B66B2AF.43D1197E@nortelnetworks.com>
Date: Tue, 31 Jul 2001 09:29:19 -0400
From: Chris Friesen <cfriesen@nortelnetworks.com>
MIME-Version: 1.0
To: subhash.sutrave@oracle.com
Cc: linux-kernel@vger.kernel.org
Subject: Re: Question about gettimeofday
In-Reply-To: <3B65F3A2.DC5F7E37@oracle.com>
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Sender: linux-kernel-owner@vger.kernel.org
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Subhash S wrote:
> 
> Hi All,
> 
> In my application I use gettimeofday very frequently, as it is system
> call on linux it is expensive, where as on Solaris it is not so. Could
> you please tell me how solaris is implemented the function gettimeofday.

While I can't tell you how Solaris implemented it, I can say that in general if
you want very frequent timing access you're probably better off using inline
assembly to get at some processor-specific timer.  On a 400Mhz G4, the
difference was about a microsecond for gettimeofday() vs about 25 nanoseconds
for the assembly code.


-- 
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