The Memory Management Glossary

This glossary is divided into pages by initial letter. Select the letter you are interested in, or select a term. Alternatively, there is the complete glossary as one document [392 kB], more suitable for printing.

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A	absolute address activation frame activation record activation stack active address address space	address translation cache address-ordered first fit aging space algebraic data type alignment alive allocate	allocation mechanism allocation policy allocation strategy allocator ambiguous reference ambiguous root arena	ATC atomic object automatic memory management automatic storage duration
B	backing store barrier⁽¹⁾ barrier⁽²⁾ base pointer best fit BIBOP big bag of pages	binary buddies bit-table bitmap bitmapped fit black blacklisting block	bounds error boxed break-table brk broken heart bucket buddy system	buffer bus error byte⁽¹⁾ byte⁽²⁾ byte⁽³⁾ byte⁽⁴⁾
C	cache⁽¹⁾ cache⁽²⁾ cache memory cache policy caching⁽³⁾ cactus stack card card marking cell Cheney collector	Cheney scan closure coalesce collect collection collection cycle collector⁽¹⁾ collector⁽²⁾ color committed	compactifying compaction composite object comprehensive concurrent garbage collection condemned set connected cons⁽¹⁾ cons⁽²⁾ conservative garbage collection	constructor⁽¹⁾ constructor⁽²⁾ continuation control stack copying garbage collection core creation space crossing map cyclic data structure
D	dangling pointer data stack dead deallocate deferred coalescing deferred reference counting	derived pointer destructor⁽¹⁾ destructor⁽²⁾ DGC direct method dirty bit	distributed garbage collection double buddies double free doubleword DRAM dynamic allocation	dynamic extent dynamic memory dynamic RAM
E	edge entry table⁽¹⁾ entry table⁽²⁾	exact garbage collection exact reference exact root	exact segregated fit execution stack exit table	extent external fragmentation
F	fencepost fencepost error Fibonacci buddies FIFO-ordered first fit file mapping finalization	first fit flip floating garbage format forwarding pointer fragmentation	frame free⁽¹⁾ free⁽²⁾ free⁽³⁾ free⁽⁴⁾ free block	free block chain free list free store freestore function record
G	garbage garbage collection garbage collector GB GC	General Protection Fault generation generation scavenging generational garbage collection generational hypothesis	gigabyte good fit GPF grain graph	gray gray list
H	handle header heap heap allocation	hit hit rate
I	immediate data immune set immutable immutable object	in-band header incremental garbage collection incremental-update indefinite extent	indexed fit indirect method infant mortality inter-generational pointer	interior pointer internal fragmentation invalid page fault inverted page table
K	kB key object kilobyte
L	large object area leaf object leak life	lifetime LIFO-ordered first fit limited-field reference count linear addressing	live load locality of reference location	logical address longword
M	machine word main memory malloc manual memory management mapped mapping mark-compact mark-sweep marking MB	megabyte memoization memory⁽¹⁾ memory⁽²⁾ memory⁽³⁾ memory⁽⁴⁾ memory bandwidth memory cache memory hierarchy memory leak	memory location memory management Memory Management Unit memory manager memory mapping memory protection misaligned miss miss rate mmap	MMU mostly-copying garbage collection mostly-exact garbage collection mostly-precise garbage collection moving garbage collector moving memory manager mutable mutator
N	natural alignment nepotism next fit node	nursery generation nursery space
O	object off-white one-bit reference count out-of-band header	overcommit overwriting error
P	padding page page fault page marking page protection page table paged in paged out paging	palimpsest parallel garbage collection perfect fit phantom reachable phantom reference physical address physical address space physical memory⁽¹⁾ physical memory⁽²⁾	physical storage pig in the python pig in the snake placement policy pointer precise garbage collection precise reference precise root premature free	premature promotion premature tenuring primary storage promotion protection protection exception protection fault protection violation
Q	quadword
R	RAM raw reachable read barrier read fault real memory⁽¹⁾	real memory⁽²⁾ reclaim recycle reference reference counting reference object	region inference register register set partitioning relocation remembered set replicating garbage collector	reserved resident resident set ROM root root set
S	sbrk scalar data type scan scavenging garbage collection SDRAM segmentation violation segmented addressing segregated fit segregated free list semi-conservative garbage collection semi-space semi-space collector sequential fit sequential store buffer shared memory	simple object simple segregated storage smart pointer snap-out snapshot-at-the-beginning soft reference softly reachable space leak spaghetti stack split SRAM SSB stack stack allocation stack frame	stack record static allocation static memory⁽¹⁾ static memory⁽²⁾ static object static RAM static storage duration sticky reference count storage storage hierarchy storage level storage management store⁽¹⁾ store⁽²⁾ strict segregated fit	strong reference strong root strong tri-color invariant strongly reachable suballocator subgraph sure reference swap space swapped in swapped out swapping sweeping
T	tabling tag tagged architecture TB⁽¹⁾ TB⁽²⁾ tenuring	terabyte termination thrash threatened set TLB trace	tracing garbage collection translation buffer transport transport snap-out treadmill tri-color invariant	tri-color marking two-space collector type-accurate garbage collection
U	unaligned unboxed undead unmapped	unreachable unsure reference unwrapped use after free
V	value object value type vector data type virtual address	virtual address space virtual memory⁽¹⁾ VM⁽¹⁾ VM⁽²⁾
W	weak reference⁽¹⁾ weak reference⁽²⁾ weak root weak tri-color invariant	weakly reachable weighted buddies weighted reference counting white	word working set worst fit wrapped	wrapper write barrier write fault
Z	ZCT zero count table

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