john gay johngayeircomnet sat 27 jul 2002 0157 wrote fri jul 26 2002 112430pm 0100 john gay wrote ago asked packages optomize pentium one person answered glibc got thinking gcc asked another list got answers dont even think suggested gcc one pointed linux scratch specifically mean one hand optimise gcc compiled make generate exact code smidge faster since gcc memory pig youd better buy ram fs cache hits keep gccs heap swap explain mean according pgcc site gcc good taking advantage pipelining features introduced pentium family pgcc patches supposed make gcc generate tighter code point compiler bugs well taken taking things slow looking things isaid pgcc site seem updated least year also looking gcc 31 series might better pgcc patches written bottom line pentiums better instruction sets original 386 instructions still support pentium also started introducing pipelining properly generated code upto 30 faster equivulent code performs function optimise gcc produce code slightly faster speed based percentage total compile time first time compiled qt libs 16m lot swap took 48 hours ive got 128m box 200mhz increase distributed long compile still considerable side look patches gcc affect code generation um ok keep mind compiler errors suck cant express enough compilers work perfectly always anything might affect opinion insane theyre hard trace youd better deep knowledge whats going either report bugs patch developers fix plus understanding gcc would need major changes get large speed boosts x86 chips understanding ive followed development intel family since 8080 generation since 386 introduced better faster instructions ie 486 introduced ieee floating point instructions incorporating fpu board first generations flaky intel disabled dodgy ones sold 486sx ie without fpu later generations better find slow 486sxs therefore 486s working fpus calculate floats faster 386s must generate proper codes take advantage pentiums improved fpu logic introduced pipelining first generations pentiums faulty fpu logic programmed pentium bug subsequent ones fine added instructions faster 486 equivulents also pipelining needs careful instruction ordering take full advantage speed improvements something compiler must know utilise full effect according pgcc site gcc poorly info seems dated gcc31x might better one areas researching closely get answer mmx added ability perform matrix calculations ints single instructions using special dma features within pentium speed two problems 1 ints useful matrix calculations floats would betters 2 something optimised well compiler need identified provided sources ie much use anyone makes great ad copy pentiumpro improved pipeline enormously properly written compiler able optimise organise code properly piii added mmxtype instructions floats useful graphicintensive programs take greate advantage must provided source code compilers usually optimise sort thing xfree86 dri two prime examples provide piii run xfree86 dri quite bit faster compiled sse instructions sure improvements p4 introduce think mostly speed improvements rather execution changes difference 386 pentiummmx yield significant speed boost optimised correctly faster floating point instructions pipelining need optimising im sure gcc optimise properly pipelining least pgcc group found significant improvements add gcc2953 gain speed improvements upto 30 30 48 hours 144 hours course none effect oi bound processes guis mostly cpu bound also finding object prelinking optimisations give even better performance qt kde another piii box could take advantage sse instructions optimise xfree86 well kevin course ive loads time hands need something keep busy least say ive sucessfully built full linux system including kde3 scratch im done cheers john gay irish linux users group iluglinuxie httpwwwlinuxiemailmanlistinfoilug unsubscription information list maintainer listmasterlinuxie sat 27 jul 2002 175812 0100 ilug optimizing pentium pt2