Xref: utzoo comp.unix.i386:3469 comp.windows.x:19649 Path: utzoo!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!samsung!uunet!ficc!peter From: peter@ficc.uu.net (Peter da Silva) Newsgroups: comp.unix.i386,comp.windows.x Subject: Re: Why do you need a 387 to run X11R3? Keywords: X, 80387 Message-ID: <4.523N2ggpc2@ficc.uu.net> Date: 11 Mar 90 21:31:41 GMT References: <9868@batcomputer.tn.cornell.edu> <20203@nuchat.UUCP> Reply-To: peter@ficc.uu.net (Peter da Silva) Organization: Xenix Support, FICC Lines: 10 In article <20203@nuchat.UUCP> steve@nuchat.UUCP (Steve Nuchia) writes: > When I cut my teeth, unix systems without FP hardware did the > emulation thing in library routines that were 10 to mayby > 100 time slower than hardware, so a program that would spend > 10% of its time doing FP would slow down by less than ten times. I'm moderately sure that Version 7 UNIX on the PDP-11 trapped an illegal instruction and emulated it, just like the 80386 UNIXes do. It might be that the PDP-11 was just quicker at handling the fault. I'm *sure* that the PDP-11 instructions were easier to parse than the 80386 ones. :->. -- _--_|\ `-_-' Peter da Silva. +1 713 274 5180. . / \ 'U` \_.--._/ v