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From: Chris Friesen <cfriesen@nortelnetworks.com>
To: subhash.sutrave@oracle.com
Cc: linux-kernel@vger.kernel.org
Subject: Re: Question about gettimeofday
Date: Tue, 31 Jul 2001 09:29:19 -0400	[thread overview]
Message-ID: <3B66B2AF.43D1197E@nortelnetworks.com> (raw)
In-Reply-To: <3B65F3A2.DC5F7E37@oracle.com>

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.


-- 
Chris Friesen                    | MailStop: 043/33/F10  
Nortel Networks                  | work: (613) 765-0557
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      reply	other threads:[~2001-07-31 13:29 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2001-07-30 23:54 Question about gettimeofday Subhash S
2001-07-31 13:29 ` Chris Friesen [this message]

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