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Message-ID: <463BB88F.4020804@aueb.gr>
Date: Sat, 05 May 2007 01:49:51 +0300
From: Diomidis Spinellis <dds@aueb.gr>
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To: Poul-Henning Kamp <phk@phk.freebsd.dk>
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Cc: arch@FreeBSD.org, Robert Watson <rwatson@FreeBSD.org>, re@FreeBSD.org
Subject: Re: Accounting changes
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Poul-Henning Kamp wrote:
> In message <463B581E.6070804@aueb.gr>, Diomidis Spinellis writes:
> 
>> On modern processors the various time values were 0, because many 
>> commands took less than 1/64s to execute [bde].  Now time values are 
>> stored with microsecond precision as float numbers.(I've written code 
>> that allows the kernel to write them without any floating point 
>> operations.)
> 
> Why on earth introduce another time format ?
> 
> Please use a standard time format please.

If we use struct timeval for the three time values the structure size 
increases considerably (especially on an amd64).  Here are some numbers:

i386
Old size=48
New size=64
New size with timeval=76

amd64
Old size=56
New size=72
New size timeval=112

On a busy system this increase can be more than 10GB / month.  Is there 
some other standard time format I've missed?

Diomidis