From mboxrd@z Thu Jan 1 00:00:00 1970 To: 9fans@cse.psu.edu From: Eyal Lotem Message-ID: <3b8ea46f@news.bezeqint.net> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7Bit References: , <015c01c130a2$0a325330$a2b9c6d4@SOMA> Subject: Re: [9fans] EROS, Vapour Date: Fri, 31 Aug 2001 08:45:21 +0000 Topicbox-Message-UUID: e7f26890-eac9-11e9-9e20-41e7f4b1d025 Boyd Roberts wrote: >> I think all the OS projects that use C++ figure that one out sooner or >> later ... > > i fear that C++ coder's brains are so damaged by the experience that > they are _incapable_ of figuring it out. snow crash, indeed. Well, EROS is moving to C, and Vapour is as far from C\C++ as you can imagine. The whole *point* behind Vapour is that it uses a safe language, rather than damage-prevention hardware protection, which allows a lot of the tests to move to compiletime, and allows interesting things, such as guaranteeing running code complies with object interfaces, without verifying this in runtime (Sometimes it could be unverifiable, or very expensive to verify). A serious advantage of Vapour for example, is since it doesn't reuqire hardware protection, it can run many threads simulataniously, all in kernel mode, all synchronizing via cheap test&set processor instructions, whereas in Plan9/etc. an expensive switch to kernel mode is required, making heavily parallel things unpractical (the cost of mutexes becomes higher than the gain of parallelism).