Cheat sheets

OS-16Cheat sheet1 pageIn a paid pack

TLB, EAT and Demand Paging

The translation path with a TLB, from hit to miss to page fault, in one figure; effective access time with a TLB for one or more page-table levels, with the TLB time counted or ignored; the hit ratio needed for a target; TLB reach and address-space identifiers; demand paging and the steps of page-fault service; effective access time with page faults, with dirty victims and combined with a TLB; copy-on-write; and equal versus proportional frame allocation. Every number was computed by script.

Diagrams from OS-16

OS-17Cheat sheet1 pageIn a paid pack

Page Replacement, Working Set

FIFO, LRU and optimal replacement traced side by side on one reference string; fault counts on the classic 20-reference string including clock and LFU; Belady's anomaly and the stack property; the clock (second chance) algorithm; implementing LRU; local versus global replacement; thrashing, the working-set model and page-fault frequency; and the solved GATE CS 2025 Set 1 Q.54 on a look-ahead window. Every trace and count was produced by a replacement simulator.