From mboxrd@z Thu Jan 1 00:00:00 1970 To: 9fans@cse.psu.edu From: "Douglas A. Gwyn" Message-ID: <3A8405FE.682356D5@arl.army.mil> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit References: <20010208062037.E5988199E1@mail.cse.psu.edu> Subject: Re: [9fans] So, once I've got the OS up how do I... Date: Fri, 9 Feb 2001 15:26:40 +0000 Topicbox-Message-UUID: 603a8d24-eac9-11e9-9e20-41e7f4b1d025 geoff@x.bell-labs.com wrote: > Forgive me for pulling a Boyd or two. This new-fangled RAM stuff is > crap; it can't even retain its contents across a power outage of a few > seconds, let alone hours. Gimme that old core memory any day; I don't > need particularly fast memory (or processors). That was *real* > technology. What we have, especially evident these days, is a multi-tiered cache. The inner cache will *always* be volatile, e.g. machine registers. At some point as one moves away from the inside, a nonvolatile cache is reached. That's where stuff has to be flushed to if you want it to last. > Seriously, can anybody explain why a rational person would buy > a Real Commercial Database? Because it's a lot of work to develop one's own high-quality DBMS. DBMSes are in fact necessary for many real applications, the canonical example being an airline reservation system, but smaller examples occur a lot. Unfortunately, researchers often don't let themselves get involved in big problems like that, so they miss the experience.