From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Chubb Date: Thu, 30 Jan 2003 04:31:19 +0000 Subject: [Linux-ia64] Re: Confused about fsystemcalls Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org >>>>> "David" = David Mosberger writes: >>>>> On Thu, 30 Jan 2003 11:07:51 +1100, Peter Chubb said: Peter> The mygetpid() call appears to return the correct value. Peter> Our figures show over an average of ten runs: --- glibc Peter> getpid() takes 579 cycles, stddev 24 --- mygetpid takes 1468 Peter> cycles, stddev 286 David> Have you tried on a McKinley? The numbers you quote for the David> standard getpid() look like for Merced. I never tried on David> Merced, though I don't know of why it shouldn't work fast, off David> hand. Worked it out -- one needs to call the mygetpid() function twice, once before the timing stuff, and once during, so we don't count the time to get the gate page into the TLB and into the cache. Timings are now 177 cycles for the mygetpid() routine as opposed to 570 for glibc (all on Itanium 1), and we're now working on gettimeofday(). Peter C