From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 11 Apr 2003 15:21:02 -0700 From: Rob Baxter To: Rob Latham Cc: linuxppc-dev@lists.linuxppc.org Subject: Re: glibc: optimized ppc bcopy Message-ID: <20030411152102.A29581@synergy> References: <20030411210449.GC92837@terizla.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20030411210449.GC92837@terizla.org>; from rob@terizla.org on Fri, Apr 11, 2003 at 04:04:49PM -0500 Sender: owner-linuxppc-dev@lists.linuxppc.org List-Id: On Fri, Apr 11, 2003 at 04:04:49PM -0500, Rob Latham wrote: > > i noticed something when comparing lmbench numbers between os x and > linux on the same hardware: linux beats os x at every category except > one: Bcopy (libc) > > *Local* Communication bandwidths in MB/s - bigger is better > ----------------------------------------------------------- > Host OS Pipe AF TCP File Mmap Bcopy Bcopy Mem Mem > UNIX reread reread (libc) (hand) read write > --------- ------------- ---- ---- ---- ------ ------ ------ ------ ---- ----- > aragorn Linux 2.4.20- 198. 216. 90.1 206.5 173.1 122.8 124.2 173. 358.3 > os-x Darwin 6.4 124. 121. 80.5 150.6 178.1 239.8 123.4 178. 411.9 > > So i looked a bit closer at glibc: there are no optimized powerpc > string or memory operations. ( later confirmed by the glibc web > pages) > > I know there are a zillion powerpc variants: would it be hard to > write assembly that works with all of them? I know almost zero about > powerpc assembly, but this might be a fun place to start learning. Of > course, if anyone else has already started such an undertaking, i'll > defer to them and go work on something else. > > For those curious, the full lmbench run can be found here: > http://terizla.org/~robl/pbook/benchmarks/lmbench-linux_vs_osx.1 > (linux does quite well :> ) > > ==rob > > -- > Rob Latham Chicago, IL USA > Another route would be the use of an AltiVec coded library variant: http://e-www.motorola.com/webapp/sps/site/overview.jsp?nodeId=03C1TR0467mKqW5Nf2d9nb Rob Baxter ** Sent via the linuxppc-dev mail list. See http://lists.linuxppc.org/