From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: X-Spam-Status: No, score=-0.9 required=5.0 tests=BAYES_00,FORGED_GMAIL_RCVD, FREEMAIL_FROM autolearn=no autolearn_force=no version=3.4.4 X-Google-Thread: 103376,f03ffdf470e3c559 X-Google-Attributes: gid103376,domainid0,public,usenet X-Google-Language: ENGLISH,ASCII-7-bit Path: g2news1.google.com!news1.google.com!border1.nntp.dca.giganews.com!nntp.giganews.com!nx02.iad.newshosting.com!newshosting.com!198.186.194.250.MISMATCH!news-xxxfer.readnews.com!transit4.readnews.com!news-out.readnews.com!postnews3.readnews.com!not-for-mail Date: Sun, 26 Oct 2008 07:11:54 -0400 From: "Peter C. Chapin" User-Agent: Thunderbird 2.0.0.17 (Windows/20080914) MIME-Version: 1.0 Newsgroups: comp.lang.ada Subject: Re: Interesting performance quirk. References: <4903c066$0$28676$4d3efbfe@news.sover.net> In-Reply-To: X-Enigmail-Version: 0.95.7 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Message-ID: <49045079$0$28711$4d3efbfe@news.sover.net> Organization: SoVerNet (sover.net) NNTP-Posting-Host: 3f87d1b0.news.sover.net X-Trace: DXC=?kIXRAo^ifDLG@jU:39aJFK6_LM2JZB_CH>Hc\Z tmoran@acm.org wrote: > I/O or cache differences? Well, the benchmark program doesn't do any I/O (except to report results at the end). I'm using the same physical hardware in both cases, but perhaps Linux and/or VMware is configuring the cache differently in some way. Or perhaps Linux provides the memory to the process in a more cache-friendly way. My program is passing over a 1 MB array from beginning to end multiple times. This is also a dual core machine, but the program has only a single task. I could try experimenting with different array sizes. Peter