Messages in this thread | | | Date | Sun, 5 Feb 2006 10:42:00 -0800 | From | "Barry K. Nathan" <> | Subject | Re: [PATCH ] VMSPLIT config options (with default config fixed) |
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On 1/11/06, Mark Lord <lkml@rtr.ca> wrote: > Greg Norris wrote: > > Is there any benefit/point to enabling HIGHMEM when using this patch, > > assuming that physical memory is smaller than the address space? For > > example, when using VMSPLIT_3G_OPT on a box with 1G of memory. > > No. In fact, there should be a (very) tiny performance gain > by NOT enabling HIGHMEM -- things like kmap() should get simpler.
Actually, IIRC if you have an x86 CPU (or x86-64 running a 32-bit kernel) which has a no-execute bit, to support that (i.e. to have a more secure system) you need to use HIGHMEM64G, no matter how much or how little RAM you have. -- -Barry K. Nathan <barryn@pobox.com> - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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