page attribute table

{{Refimprove|date=October 2009}}

The page attribute table (PAT) is a processor supplementary capability extension to the page table format of certain x86 and x86-64 microprocessors. Like memory type range registers (MTRRs), they allow for fine-grained control over how areas of memory are cached, and are a companion feature to the MTRRs.{{cite web | title=Intel 64 and IA-32 Architectures Software Developer's Manual Volume 3A: System Programming Guide, Part 1 | url=http://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-software-developer-vol-3a-part-1-manual.pdf | publisher=Intel | date= | access-date=2017-05-30}}

Unlike MTRRs, which provide the ability to manipulate the behavior of caching for a limited number of fixed physical address ranges, Page Attribute Tables allow for such behavior to be specified on a per-page basis, greatly increasing the ability of the operating system to select the most efficient behavior for any given task.{{cite web | title=PAT (Page Attribute Table) in Linux kernel docs |url=https://www.kernel.org/doc/html/latest/x86/pat.html | date= | access-date=2020-06-02}}

Processors

The PAT is available on Pentium III and newer CPUs, and on non-Intel CPUs.

See also

References