Characteristics of a typical modern PC or Workstation
Everyone should have a general idea of the power and capacity
of current computers. Here's a list of numbers you
should have an intuitive feel for. They are intended as
figures suitable for back-of-the-envelop calculations.
There are certainly examples of computers whose
characteristics do not fall in these ranges.
- Clock speed: 50 to 300 MHz.
- Clock cycle time: 3 to 20 ns.
- Cache size: 8 KByte to 512 KByte.
- Cache miss penalty: 5 to 20 cycles.
- CPI (not counting cache miss penalties): 3 to .3 cycles/instruction.
- Main (physical) memory size: 8MByte to 256MByte.
- Virtual address length: 32 or 64 bits.
- Capacity of a disk: 300 MByte to 10 GByte.
- Bandwidth from disk: 1 to 20 MByte/sec.
- Disk latency: 5 to 50 msec.
- Page size: 4 KByte to 64 KByte.
- TLB size: 64 to 1024 entries.
Note to future historians: this was written in April, 1997.