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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