Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!ficc!peter From: peter@ficc.uu.net (Peter da Silva) Newsgroups: comp.os.mach Subject: Re: Mach performance? [Long] Message-ID: Date: 28 Dec 89 01:40:11 GMT References: <7372@pt.cs.cmu.edu> <14246@jumbo.dec.com> <1482@crltrx.crl.dec.com> Reply-To: peter@ficc.uu.net (Peter da Silva) Organization: Xenix Support, FICC Lines: 14 In article Richard.Draves@CS.CMU.EDU writes: > Off-machine RPCs are relatively slow because they aren't handled > directly by the kernel. A user-level process, called the netmsgserver, > handles network IPC. Which is as it should be, right? One of the design goals of Mach was to move stuff like this out of the kernel, then improve performance by speeding up context switches and clever use of virtual memory. I might be all wet on this, but by making the user pages containing the data to be sent copy-on-write and mapping them into the netmsgserver you could get rid of all the extra copies. And context switch time should already be quite low. Merely a SMOP. -- `-_-' Peter da Silva. +1 713 274 5180. . 'U` Also or . "It was just dumb luck that Unix managed to break through the Stupidity Barrier and become popular in spite of its inherent elegance." -- gavin@krypton.sgi.com