site_archiver@lists.apple.com Delivered-To: darwin-kernel@lists.apple.com On Jun 5, 2006, at 7:52 AM, Andrew Gallatin wrote: I'm simply trying to account for why it takes ~8x as long for a simple syscall, Which "simple" syscall? and ~4x as long to get an ioctl into our driver when running MacOSX vs ppc64 linux on the same hardware. On x86 linux, when switching from the 1G/3G split to 4G/4G, we see a similar bloat of ioctl times. I had simply assumed that the 4G address space was the issue. Perhaps more of the blame lies elsewhere. = Mike _______________________________________________ Do not post admin requests to the list. They will be ignored. Darwin-kernel mailing list (Darwin-kernel@lists.apple.com) Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/darwin-kernel/site_archiver%40lists.a... Syscall entry/exit is certainly more expensive on Mac OS than Linux. It comprises such a miniscule part of the elapsed system time on typical systems that whilst it shows up a lot on micro-benchmarks, it's not a very rewarding target for optimisation. This email sent to site_archiver@lists.apple.com