virtual Memory
1 Virtual Memory
Outline Virtual space Address translation Accelerating translation with a tlB Multilevel page tables Different points of view Suggested reading: 10. 1-10.6 TLB: Translation lookaside buffers
2 Outline • Virtual Space • Address translation • Accelerating translation – with a TLB – Multilevel page tables • Different points of view • Suggested reading: 10.1~10.6 TLB: Translation lookaside buffers
10.1 Physical and Virtual Addressing
3 10.1 Physical and Virtual Addressing
Physical Addressing Attributes of the main memory Organized as an array of m contiguous byte-sized cells Each byte has a unique physical address(PA) started from O physical addressing A CPU use physical addresses to access memory Examples Early PCs, DSP, embedded microcontrollers, and Cray supercomputers Contiguous:临近的
4 Physical Addressing • Attributes of the main memory – Organized as an array of M contiguous byte-sized cells – Each byte has a unique physical address (PA) started from 0 • physical addressing – A CPU use physical addresses to access memory • Examples – Early PCs, DSP, embedded microcontrollers, and Cray supercomputers Contiguous: 临近的
Physical Addressing Main menor Physical address CPU (PA) 4 012345678 Data word Figure 10.1 P693
5 Physical Addressing Figure 10.1 P693