From be4193108513f02439a211a92fd80e0651f6721b Mon Sep 17 00:00:00 2001 From: Thomas Schwinge Date: Wed, 30 Nov 2011 21:21:45 +0100 Subject: IRC. --- microkernel/mach/gnumach/memory_management.mdwn | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) (limited to 'microkernel') diff --git a/microkernel/mach/gnumach/memory_management.mdwn b/microkernel/mach/gnumach/memory_management.mdwn index 43b99d83..ca2f42c4 100644 --- a/microkernel/mach/gnumach/memory_management.mdwn +++ b/microkernel/mach/gnumach/memory_management.mdwn @@ -80,3 +80,25 @@ IRC, freenode, #hurd, 2011-06-09 wow i remember the linux support for 4G/4G split when there was enough RAM to fill the kernel space with struct page entries + + +IRC, freenode, #hurd, 2011-11-12 + + well, the Hurd doesn't "artificially" limits itself to 1.5GiB + memory + i386 has only 4GiB addressing space + we currently chose 2GiB for the kernel and 2GiB for the userspace + since kernel needs some mappings, that leaves only 1.5GiB usable + physical memory + Hm? 2GiB for kernel, 2GiB for userspace, 500MiB are used for + what? + for mappings + such as device iomap + contiguous buffer allocation + and such things + Ah, ok. You map things in kernel space into user space then. + linux does the same without the "bigmem" support + no, just in kernel space + kernel space is what determines how much physical memory you can + address + unless using the linux-said-awful "bigmem" support -- cgit v1.2.3