BSDCan2011 - Final (with audio).5

BSDCan 2011
The Technical BSD Conference

Kirk McKusick
Day Talks - 2 - 2011-05-14
Room DMS 1160
Start time 13:30
Duration 01:00
ID 219
Event type Lecture
Track Hacking
Language used for presentation English

Superpages in FreeBSD

This talk describes why superpages are useful and how they are supported in the FreeBSD kernel.

This talk will describe the addition of superpage support to the FreeBSD 8 kernel on the Intel PC architecture. Superpages aggregate together standard-sized hardware pages into much larger "superpages". Each superpage requires only one entry in the page table replacing the numerous entries used by the standard-sized hardware pages. The result is much smaller page tables and greatly increased coverage by the TLB, producing much higher TLB hit rates for large processes. While superpages are used for all appropriate processes with no explicit request by the applications, understanding how they work will enable you to write your applications to make optimal use of them.