Date: Mon, 8 Jan 1996 15:41:36 -0700 (MST) From: Terry Lambert <terry@lambert.org> To: davidg@root.com Cc: terry@lambert.org, gpalmer@westhill.cdrom.com, wosch@cs.tu-berlin.de, hackers@freebsd.org Subject: Re: large files Message-ID: <199601082241.PAA10640@phaeton.artisoft.com> In-Reply-To: <199601082123.NAA01772@corbin.Root.COM> from "David Greenman" at Jan 8, 96 01:23:13 pm
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> >I believe the restriction is based on mmap'ed files taking a portion > >of the kernel address space equal to their size. This is arguably > >a design flaw in the mmap implementation. > > > >Really, mmap wants to operate on a demand paged window and arrange > >the vnode as the mappable entity so that it can be shared between > >various processes without taking kernel address space to do it. > > This is absolutely, 100% wrong. It does NOT work like that. Actually, John says it does. As I stated in my followup to John, I screwed up SHMEM and SHLIB thikning about mmap() as the underlying implementation mechanism. > >You need to talk to the VM guys about fixing this. > > Right, and you should look at the code someday. No need to go off half-cocked. If you were as familiar with the code as you always expect me to be, then you would have realized that what I had was a labelling error, and instead of being an ad hominim attack, your response might have been: "Er... aren't you confusing mmap() and the shared memory implementation here?" To which I would have had to say: "Oh duh, pass the hat!" (Which is what I said to John). Regards, Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.
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