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Chapter 10 Storage management. Elements requiring storage Programmer and system controlled storage Static Storage Management Heap Storage Management. Elements requiring storage. Code segments for translated user programs System run-time programs - e.g. libraries
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Chapter 10 Storage management • Elements requiring storage • Programmer and system controlled storage • Static Storage Management • Heap Storage Management
Elements requiring storage • Code segments for translated user programs • System run-time programs - e.g. libraries • User defined data structures and constants • Subprogram return points • Referencing environments
Elements requiring storage • Temporaries in expression evaluation • Temporaries in parameter transmission • Input-Output buffers • Miscellaneous system data - tables etc
Operations that require storage allocation • Subprogram call and return operations - creation and deletion of activation records • Explicit data structure creation and destruction operations • Component insertion and deletion operations
Programmer and system controlled storage • Pros and cons: • Programmer knows when to allocate / free storage. • Programmer may interfere with the system-controlled storage management • Storage-Management Phases • Initial allocation • Recovery • Compaction and reuse
Static Storage Management • Static allocation : • allocation during translation that remains fixed throughout execution. • Does not allow recursive subprograms
Dynamic Allocation:Heap Storage Management Memory used for dynamic allocation of data objects in somewhat unstructured manner is called heap storage. OS HEAP STACK
Heap Storage Management • Tasks: • allocation, • recovery, • dangling references • garbage collection • compaction, • reuse • Fixed size elements • Variable size elements
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