From mboxrd@z Thu Jan 1 00:00:00 1970 MIME-Version: 1.0 In-Reply-To: <4f34febc0904190058u1507f60fldc51ab3eab1f09fe@mail.gmail.com> References: <4f34febc0904190058u1507f60fldc51ab3eab1f09fe@mail.gmail.com> Date: Sun, 19 Apr 2009 09:27:43 -0500 Message-ID: From: Eric Van Hensbergen To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: Re: [9fans] "FAWN: Fast array of wimpy nodes" (was: Plan 9 - the next 20 years) Topicbox-Message-UUID: e89d3378-ead4-11e9-9d60-3106f5b1d025 On Sun, Apr 19, 2009 at 2:58 AM, John Barham wrote: > I certainly can't think ahead 20 years but I think it's safe to say > that the next 5 (at least doing HPC and large-scale web type stuff) > will increasingly look like this: > http://www.technologyreview.com/computing/22504/?a=3Df, which talks > about building a cluster from AMD Geode (!) nodes w/ compact flash > storage. =A0Sure it's not super-fast, but it's very efficient per watt. > If you had more cash you might substitute HE Opterons and SSD's but > the principle is the same. > We thought this was the future several years ago (http://bit.ly/16ZWjc), but couldn't convince the company that such an approach would win out over big iron. Of course, if you look at Blue Gene, it's really just a massive realization of this model with several really tightly coupled interconnects. > > Apparently they use the above cluster to implement some type of > distributed memcached style cache. > I'm not convinced that such ad-hoc DSM models are the way to go as a general principal. Full blown DSM didn't fair very well in the past. Plan 9 distributed applications take a different approach and instead of sharing memory they share services in much more of a message passing model. This isn't to say that all caches are bad -- I just don't believe in making them the foundation of your programing model as it will surely lead to trouble. -eric