On 10/19/2011 08:20 PM, Richard Pieri wrote: > On Oct 18, 2011, at 8:56 PM, Edward Ned Harvey wrote: >> Nothing will support a 64bit guest on a 32bit host. > I digress here, because this is not strictly true. IBM devised a method for > running some 64-bit applications on 32-bit AIX servers. I digress because > this was not virtualization. It was a clever use of a wrapper that mapped > 64-bit functions to their 32-bit counterparts and then mapped the returns > back as 64-bit data. It was terribly slow, totally unsuited for production > use. IBM did it for developers to test their code given older hardware. > > VMware could have made it happen. Back before VT-x and AMD-V, VMware didn't > really virtualize the x86. VMware *emulated* the x86. Ask Google about > trap-and-emulate and why it doesn't work on the Intel architecture. That's > why-for the roughly 50% performance hit compared to what we have today with > VT-x/AMD-V. VMware could have incorporated AMD64 in their x86 emulator. It > would have been abominably slow, much like IBM's 64-bit to 32-bit mapping > trick. VT-x and AMD-V made this a non-issue. There are 2 BIOS flags in the Thinkpad, VT-d and Virtualization. Both have to be set for Pl;ayer to host 64-bit guests.
-- Jerry Feldman <[email protected]> Boston Linux and Unix PGP key id:3BC1EB90 PGP Key fingerprint: 49E2 C52A FC5A A31F 8D66 C0AF 7CEA 30FC 3BC1 EB90 _______________________________________________ Discuss mailing list [email protected] http://lists.blu.org/mailman/listinfo/discuss
