WSClock page replacement algorithm
E651431
The WSClock page replacement algorithm is an operating system memory management technique that combines the working set model with a clock-based mechanism to efficiently decide which pages to evict.
Statements (46)
| Predicate | Object |
|---|---|
| instanceOf |
memory management algorithm
ⓘ
operating system concept ⓘ page replacement algorithm ⓘ |
| avoidsEvicting |
dirty pages when possible
ⓘ
recently used pages ⓘ |
| basedOn |
clock page replacement algorithm
NERFINISHED
ⓘ
working set model ⓘ |
| category | operating systems memory management ⓘ |
| combines |
clock-based mechanism
ⓘ
working set model ⓘ |
| hasAdvantage |
better approximation of working set than simple clock
ⓘ
good performance under varying workloads ⓘ low overhead compared to full working set algorithm ⓘ |
| hasGoal |
approximate working set behavior
ⓘ
efficient page eviction ⓘ limit paging overhead ⓘ reduce page fault rate ⓘ |
| hasParameter | working set window size ⓘ |
| hasTradeoff | choice of working set window affects performance ⓘ |
| isComparedTo |
LRU page replacement algorithm
NERFINISHED
ⓘ
clock page replacement algorithm ⓘ working set page replacement algorithm ⓘ |
| isUsedFor |
deciding which page to evict on page fault
ⓘ
managing physical memory frames ⓘ |
| maintains |
circular list of page frames
ⓘ
per-page modify bit ⓘ per-page reference bit ⓘ per-page time stamp of last use ⓘ |
| oftenAssumes | hardware support for modify bits ⓘ |
| operatesIn |
demand paging system
ⓘ
virtual memory system ⓘ |
| prefersToEvict | clean pages ⓘ |
| relatedTo |
Belady anomaly
NERFINISHED
ⓘ
thrashing control ⓘ |
| requires | hardware support for reference bits ⓘ |
| selectsForEviction |
pages outside working set
ⓘ
unreferenced pages older than working set window ⓘ |
| usesConcept |
modify bit
ⓘ
page frame ⓘ reference bit ⓘ time of last use ⓘ virtual memory ⓘ working set ⓘ working set window ⓘ |
| usesDataStructure |
circular buffer
ⓘ
clock hand pointer ⓘ |
Referenced by (1)
Full triples — surface form annotated when it differs from this entity's canonical label.