The preinstalled OS is not even using 64-bit mode [LWN.net]

The preinstalled OS is not even using 64-bit mode

Posted Feb 21, 2007 3:25 UTC (Wed) by rafdz (guest, #41427)
In reply to: The preinstalled OS is not even using 64-bit mode by mikov
Parent article: Dell users demand more Linux options (ZDNet UK)

i think that pointer compression should be used even on 32 bits by compressing pointers to 16 bits or even 8 bits.i don't think that this is that complicated, one could simply implement custom allocators with memory areas of say 256 Kbytes (64K words ) or 512Kbytes.i think that neither gcc nor linux kernel should use 64 bits pointers in general(they should be used only in some specific cases).switching to compressed pointers would take some efforts, but it's the only way to fully exploit current hardware capabilities.

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The preinstalled OS is not even using 64-bit mode

Posted Feb 21, 2007 18:32 UTC (Wed) by RareCactus (guest, #41198) [Link]

Hardware is a moving target.

No doubt in a few years, 64-bit pointers will be the norm, and 32-bit pointers will be supported the same way real-mode applications are in Windows-- poorly, and slowly through emulation.

Using 16-bit pointers (which is only possible in real mode) is already a huge performance hit. The chip designers support it, but they don't care how fast it is, because most people only ever are in this mode when they're looking at the BIOS.

I don't understand what you're talking about with 8-bit pointers, since the x86 has never had those.