Xref: utzoo comp.arch:8695 comp.sys.intel:749 Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ucbvax!decwrl!sun!imagen!atari!portal!cup.portal.com!bcase From: bcase@cup.portal.com (Brian bcase Case) Newsgroups: comp.arch,comp.sys.intel Subject: Re: i860 overview (long) Message-ID: <15562@cup.portal.com> Date: 8 Mar 89 19:59:44 GMT References: <807@microsoft.UUCP> <92634@sun.uucp> <13322@steinmetz.ge.com> Organization: The Portal System (TM) Lines: 13 >One problem with any chip which requires alligned data is that >performance suffers when addressing bytes, to the point that a program >may become impractical. One of the people here checked his Sun-30 >(68020) against his Sun-4 (SPARC). The three ran troff about 5x faster. >This doesn't mean RISC is bad in a workstation, but it can have >performance problems in software we take for granted. Now wait a minute; can anyone substantiate this claim? It seems that something else must have been wrong: I might believe that the 020 could be faster for *unaligned* data, but not 5 times faster. The SPARC has load/store byte, halfword, and word instructions that work just fine as long as data is properly aligned. And I can't imagine the compiler unaligning things on purpose. Could you clarify this?