Path: utzoo!news-server.csri.toronto.edu!cs.utexas.edu!wuarchive!uwm.edu!bbn.com!fkittred From: fkittred@bbn.com (Fletcher Kittredge) Newsgroups: comp.os.mach Subject: Re: Mach RPC Throughput... Message-ID: <63274@bbn.BBN.COM> Date: 15 Mar 91 12:51:49 GMT References: Sender: news@bbn.com Reply-To: fkittred@spca.bbn.com (Fletcher Kittredge) Distribution: comp Organization: Bolt Beranek and Newman Inc., Cambridge MA Lines: 42 In article morse@quark.mpr.ca (Daryl Morse) writes: > >Now that we have been throroughly reminded of some of the differences >between Amoeba and Mach, I have a question regarding the throughput of >the Mach RPC. First a bit of background... ... >Why is the >throughput of the Mach RPC so much slower than the other OSes? Are the >respective RPCs different enough that throughput is a meaningless >"apples and oranges" comparision? Has the Mach RPC simply not been >optimized as heavily as that of the other OSes? > The answer is that this is an example of comparing an old version of piece of software with a new version of a competing package. Given the dates cited in your article, the Mach RPC tested would be version 2.5 or lower. For Mach 3.0, the RPC system was completely re-written by Richard Draves. One of the results was a real increase in speed. You will be wanting to read the paper "A Revised IPC Interface", Richard Draves, Proceedings of the October 1990 "Machnix" Conference, Burlington Vt. An example of the increase in performance is that the null RPC now takes 125 micro-seconds instead of 210 micro-seconds. >Thanks. your welcome ;-), fletcher > >-- >Daryl Morse | Voice : (604) 293-5476 >MPR Teltech Ltd. | Fax : (604) 293-5787 >8999 Nelson Way, Burnaby, BC | E-Mail: morse@quark.mpr.ca >Canada, V5A 4B5 | quark.mpr.ca!morse@uunet.uu.net 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