From mboxrd@z Thu Jan 1 00:00:00 1970 From: dexen deVries To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Date: Fri, 16 Sep 2011 09:52:58 +0200 User-Agent: KMail/1.13.6 (Linux/3.1.0-rc6-l39+; KDE/4.5.5; x86_64; ; ) References: <103b012cdb5c55bca54c751bb88fb57c@brasstown.quanstro.net> <787846152d3d67fec1b9cb19e132bfb9@harness.quanstro.net> In-Reply-To: <787846152d3d67fec1b9cb19e132bfb9@harness.quanstro.net> MIME-Version: 1.0 Content-Type: Text/Plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-Id: <201109160952.59092.dexen.devries@gmail.com> Subject: Re: [9fans] gar nix! Topicbox-Message-UUID: 2318b75a-ead7-11e9-9d60-3106f5b1d025 On Friday 16 of September 2011 08:46:51 erik quanstrom wrote: > On Fri Sep 16 01:57:04 EDT 2011, rminnich@gmail.com wrote: > > for the 2M pages -- I'm willing to see some measurement but let's get > > the #s -- I've done some simple measurements and it's not the hit one > > would expect. These new machines have about 10 GB/s bandwidth (well, > > the ones we are targeting do) and that translates to sub-millisecond > > times to zero a 2M page. Further, the text page is in the image cache. > > So after first exec of a program, the only text issue is locating the > > page. It's not simply a case of having to write 6M each time you exec. >=20 > however, neither the stack nor the heap are. that's 4MB that need to be > cleared. that sounds like an operation that could take on the order of > ms, and well-worth measuring. keep a pool of clean pages in kernel. upon exec use fresh ones for stack an= d=20 heap, clean old ones in background. employ DMA controler when possible. =2D-=20 dexen deVries [[[=E2=86=93][=E2=86=92]]] =46or example, if the first thing in the file is: an XML parser will recognize that the document is stored in the traditional= =20 ROT13 encoding. (( Joe English, http://www.flightlab.com/~joe/sgml/faq-not.txt ))