user
49 lines
1.1 KiB
Plaintext
49 lines
1.1 KiB
Plaintext
@startuml
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scale 620 height
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top to bottom direction
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skinparam backgroundColor transparent
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skinparam shadowing false
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skinparam defaultFontName Monospace
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skinparam defaultFontSize 10
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skinparam classBorderColor #2c7794
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skinparam classBackgroundColor #edf6fa
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skinparam ArrowColor #8095a1
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title A2 STRUCTURE — in-band metadata and address order
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class "01 Block header" as HEADER {
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next : BlockLink_t*
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size : size_t
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}
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class "Allocated block" as ALLOC {
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02 header + 13 byte request
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aligned total = 32 bytes
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payload begins after header
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}
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class "03 Free remainder" as REM {
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own header
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size = 224 bytes
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}
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HEADER *-- ALLOC : precedes payload
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ALLOC -down-> REM : split preserves 256
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class "04 Address-ordered free list" as LIST {
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previous < inserted < current
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}
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class "05 Right neighbour" as RIGHT {
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block + block.size == current
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}
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class "06 Left neighbour" as LEFT {
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previous + previous.size == block
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}
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REM -down-> LIST : insert by address
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LIST -down-> RIGHT : join first
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RIGHT -down-> LEFT : then join left
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note right of LIST
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Ordering makes both physical
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neighbours locally visible.
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end note
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@enduml
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