Dear Ben, > Although PAE supports up to 64 GB RAM, everything the kernel accesses > must be mapped into 1 GB of virtual address space (about 880 MB of > persistently mapped 'normal memory', plus temporary mappings of the > remaining 'high memory'). The use of such a large amount of high memory > is problematic, though I don't know whether it entirely explains this > behaviour. (The memory stats don't seem to account for much of the > normal memory, as there is ~40 MB free but the various classes of > allocations seem to add up to only ~300 MB.) > > These machines should all be installed with the amd64 kernel. Is there > any reason you would prefer not to do that? Perhaps the kernel flavour > selection in the installer should be changed to favour that based on the > RAM size, though I'm not sure what the critical value should be.
Are you suggesting that the kernel lies, that 32-bit cannot handle 64GB? Would it help to test the issue on a 16GB machine (I have one with 2*X5460 CPUs and one with single i5-3570), or with 24GB (have several with 2*E5335 to 2*X5460) I have seen recommendations to use 64-bit amd64. I am somewhat reluctant on "jumping ship": I want continuity (when I upgrade by installing a little more memory), want similarity between my various machines; and have observed 32-bit being "faster" in some situations. But really: this is a bug in the 32-bit build. Do I know that the same or similar or worse bugs are not present also in the 64-bit build off the same sources? Thanks, Paul Paul Szabo p...@maths.usyd.edu.au http://www.maths.usyd.edu.au/u/psz/ School of Mathematics and Statistics University of Sydney Australia -- To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
