[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Bug#295678: kernel-image packages with CONFIG_HIGHMEM64G=y enabled

> I can't say I'm a fan of adding another flavour.  How many people are
> actually using >4GB of memory on x86?  I suspect (or hope) that people
> who are going to be doing those sorts of things will be using x86_64
> and ia64 hardware.  Christian's problem, aiui, is simply that the kernel
> sees 3.5GB instead of 4GB.  I'm not sure whether this is by design, or is
> a bug, but I'd much rather see that fixed instead.

This is not really a bug, see:

The 3.5GB-4GB address space is reserved for PCI devices, so, as only 4GB
can be adressed on 32bits proc, there is an address space shortage which
prevents using the 3.5GB-4GB RAM.

So the only solution is to enable CONFIG_HIGHMEM64G to increase the
address space so that the 3.5GB-4GB RAM become addresseable.

However I would be interested in some numbers/benchmarks on the
performance penalty of the PAE mode. Is this worth 512MB of additionnal


Reply to: