From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Mosberger Date: Thu, 30 Jan 2003 04:39:56 +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 >>>>> On Thu, 30 Jan 2003 15:31:19 +1100, Peter Chubb said: Peter> Worked it out -- one needs to call the mygetpid() function Peter> twice, once before the timing stuff, and once during, so we Peter> don't count the time to get the gate page into the TLB and Peter> into the cache. Yes, that makes a big difference. Here is what I see for getppid() on a McKinley: getppid cycles: 1410 79 56 54 54 54 54 54 54 54 (I just added getppid() and I also added code to patch over the McKinley E9 workaround on CPUs that don't need it.) Peter> Timings are now 177 cycles for the mygetpid() routine as Peter> opposed to 570 for glibc (all on Itanium 1), Ah, that's much better. Peter> and we're now working on gettimeofday(). Cool. I assume you're doing this based on the lock-free version that Andrew Morton has in his latest patch? --david