From mboxrd@z Thu Jan 1 00:00:00 1970 From: Linus Torvalds To: Dave Lukes Cc: 9fans <9fans@cse.psu.edu> Subject: Re: [9fans] Re: Threads: Sewing badges of honor onto a Kernel In-Reply-To: <1077899988.21772.196.camel@zevon> Message-ID: References: <290c102a9496a5f2a33af7922d24382e@yourdomain.dom> <1077884597.21772.21.camel@zevon> <1077899988.21772.196.camel@zevon> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Date: Fri, 27 Feb 2004 09:05:52 -0800 Topicbox-Message-UUID: 003f3c04-eacd-11e9-9e20-41e7f4b1d025 On Fri, 27 Feb 2004, Dave Lukes wrote: > > I said: user mode using it: show me the example! Hey. Ask why Plan-9 doesn't use the shared stack either. I bet it's because tons of programs broke. [ Hint: Dave just explained the Plan9 thread model to me: the "private stack" ends up not being used as a stack at all. The real stacks end up being malloc'ed for each thread (in _shared_ space), and the "private stack" area only ends up being a TLS segment. ] I wouldn't know about whatever apps a private stack would break, because I was never crazy enough to think that a private stack was a good diea. > i.e. no example. Hey, _you're_ the one with the crazy idea. As such, the burden of proof is on you to show that it isn't crazy. > One other detail: as far as I can see, > your examples all use shared memory as a cheap substitute > for message passing: why? Because message passing is idiotic, when the real hardware just passes pointers around? Because you can't put complex data structures in a message without silly encodings that make performance plummet like a stone? Methinks you have read a few too many papers about microkernels, without actually seeing the real world. Hint: you can't message-pass a hash table that describes 200 megabytes worth of filesystem names. Welcome to the real world, Neo. Stop playing around with those examples your professors showed you. They had no relevance. Linus