Virtual Memory Workbench

This workbench shows the operation of a virtual memory system. There are four processes which generate page references in a virtual address space composed of 32 pages (numbered from 0 to 31). Main memory holds 16 page frames. The translation lookaside buffer (TLB) contains the 4 least recently used translation pairs. When there is a context switch, the page table for the new process in execution is displayed and all the entries in the TLB are purged. Page frames change colors depending on the color of the process that has a page in the page frame. Empty page frames are painted in light pink. The number of the page stored in a page frame is shown in the middle of the page frame. The number of the page frame is shown at the top left corner of the page frame. The workbench can be executed in a step-by-step mode by pushing the STEP button or in a continuous mode by pushing the START button. You will see controls that allow you to change the animation speed. The right hand side of the screen shows statistics on page faults and TLB hit ratios.

Workbench