Date: Sun, 17 Feb 2002 23:33:40 -0800 (PST) From: Matthew Dillon <dillon@apollo.backplane.com> To: Terry Lambert <tlambert2@mindspring.com> Cc: Bruce Evans <bde@zeta.org.au>, Poul-Henning Kamp <phk@critter.freebsd.dk>, Julian Elischer <julian@elischer.org>, Alfred Perlstein <bright@mu.org>, arch@FreeBSD.ORG, jhb@FreeBSD.ORG, peter@wemm.org, jake@locore.ca Subject: Re: gettimeofday() and crhold()/crfree() (was Re: gettimeofday()andcopyout().Is copyout() MPSAFE on non-i386 archs? ) Message-ID: <200202180733.g1I7Xej12207@apollo.backplane.com> References: <20020218151249.E4728-100000@gamplex.bde.org> <3C70AB8B.96589869@mindspring.com>
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:.4nsec * 22,000 transactions/sec * 5 timestamps/transaction
:= 440us/sec spent on time stamps.
:
:Up that to 2uS and... = 220ms/sec on time stamps = ~1/4 of
:all available time spent on time stamps.
:
:[ ... other stuff not really applicable; can discuss why
: off list, if necessary ... ]
:
:-- Terry
This is a meaningless exercise if you don't take into account
everything the program in question is doing on a per transaction
basis. To say that a single 2uS system call takes 25% of available
resources also infers that all your other code requires only 6uS
per transaction of overhead, which means it doesn't do very much eh?
-Matt
Matthew Dillon
<dillon@backplane.com>
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