Path: utzoo!utgpu!news-server.csri.toronto.edu!bonnie.concordia.ca!thunder.mcrcim.mcgill.edu!snorkelwacker.mit.edu!usc!wuarchive!mit-eddie!bbn.com!fkittred From: fkittred@bbn.com (Fletcher Kittredge) Newsgroups: comp.os.mach Subject: Re: Bytes in Mach 3.0? Message-ID: <62780@bbn.BBN.COM> Date: 18 Feb 91 01:50:13 GMT References: <2981@fai.UUCP> <1991Feb13.170901@ibmpa.awdpa.ibm.com> <1991Feb14.220240.26795@ico.isc.com> <62753@bbn.BBN.COM> <1991Feb15.214231.21348@watmath.waterloo.edu> Sender: news@bbn.com Reply-To: fkittred@spca.bbn.com (Fletcher Kittredge) Organization: Bolt Beranek and Newman Inc., Cambridge MA Lines: 46 In article <1991Feb15.214231.21348@watmath.waterloo.edu> gamiddle@watmath.waterloo.edu (Guy Middleton) writes: >In article <62753@bbn.BBN.COM> fkittred@spca.bbn.com (Fletcher Kittredge) writes: >> In article <1991Feb14.220240.26795@ico.isc.com> rcd@ico.isc.com (Dick Dunn) writes: >> >My confusion stems from the understanding that the Mach 3.0 kernel >> >is supposed to be the "micro-kernel" version, and the belief that a 240 Kb >> >kernel cannot reasonably be labeled "micro". >> > >> >Explanation/clarification, please? >> >> Sure, how familar are you with modern operating systems? 245K of text >> with 31k of data is *VERY* small for a UNIXoid kernel. For example, >> here is the size of the Unix kernel on Sun, DEC and HP systems: >> >[various huge numbers deleted] > >I don't think it is all that small. 4.3bsd on a VAX has text of similar size: > >text data bss dec hex >229784 166320 90048 486152 76b08 > >Note that it is probably more fair to compare 386 with VAX binaries than with >SPARC, MIPS or HP-PA, since RISC code tends to occupy more space. Sorry for confusing the issue by posting the figures for Sun O/S, Ultrix and HP-UX, even though they were enlightening. The point is that those operating systems are not modern operating systems; neither is 4.3 BSD, or the ninth Edition of Unix. All of the above are the last of the previous generation of operating systems. Modern operating systems are designed from the ground up to support parallel processors (NUMA and UMA), distributed systems and object oriented programming. the above systems are single threaded, and have distributed name services, shared memory and IPC/RPC tacked on as an afterthought. A better comparision would be between Chorus, Ameoba and Mach 3.0. regards, fletcher Fletcher Kittredge Platforms and Tools Group, BBN Software Products 10 Fawcett Street, Cambridge, MA. 02138 617-873-3465 / fkittred@bbn.com / fkittred@das.harvard.edu