V8 Minor GC

Transcript

1. Minor GC (Scavenge)
   1. Let us assume that there are already objects on the “to-space” when we
   start(Blocks 01 to 06 marked as used memory)
   2. The process creates a new object(07)
   3. V8 tries to get required memory from the from-space, but there is no free
   space in there to accommodate our object and hence V8 triggers minor GC
   

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2. Minor GC
   Heap memory
   New space (Young generation)
   Old generation
   (Old space)
   Pointer space
   Orphan Used memory Free memory
   Large object space Code space
   Cell space
   Property cell space
   Map space
   Data space
   From-space To-space
   01 02 03
   04
   05 06
   07
   (new object)
   

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3. Minor GC
   Heap memory
   New space (Young generation)
   Old generation
   (Old space)
   Pointer space
   Orphan Used memory Free memory
   Large object space Code space
   Cell space
   Property cell space
   Map space
   Data space
   From-space To-space
   01
   02 03
   04
   05 06
   07
   (new object)
   

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4. Minor GC
   Heap memory
   New space (Young generation)
   Old generation
   (Old space)
   Pointer space
   Orphan Used memory Free memory
   Large object space Code space
   Cell space
   Property cell space
   Map space
   Data space
   From-space To-space
   01
   02 03
   04
   05
   06
   07
   (new object)
   

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5. Minor GC
   Heap memory
   New space (Young generation)
   Old generation
   (Old space)
   Pointer space
   Orphan Used memory Free memory
   Large object space Code space
   Cell space
   Property cell space
   Map space
   Data space
   From-space To-space
   01
   02 03
   04
   05
   06
   07
   (new object)
   

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6. Minor GC
   Heap memory
   New space (Young generation)
   Old generation
   (Old space)
   Pointer space
   Orphan Used memory Free memory
   Large object space Code space
   Cell space
   Property cell space
   Map space
   Data space
   To-space From-space
   01 03 05
   07
   (new object)
   

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7. Minor GC
   Heap memory
   New space (Young generation)
   Old generation
   (Old space)
   Pointer space
   Orphan Used memory Free memory
   Large object space Code space
   Cell space
   Property cell space
   Map space
   Data space
   To-space From-space
   01 03 05
   07
   (new object)
   

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8. Second Minor GC
   1. Let us assume that some time have passed and there are more objects on
   the “from-space” now(Blocks 07 to 09 marked as used memory)
   2. The process creates a new object(10)
   3. V8 tries to get required memory from the from-space, but there is no free
   space in there to accommodate our object and hence V8 triggers second
   minor GC
   

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9. Minor GC
   Heap memory
   New space (Young generation)
   Old generation
   (Old space)
   Pointer space
   Orphan Used memory Free memory
   Large object space Code space
   Cell space
   Property cell space
   Map space
   Data space
   To-space From-space
   01 03 05
   07 08 09
   10
   (new object)
   

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10. Minor GC
    Heap memory
    New space (Young generation)
    Old generation
    (Old space)
    Pointer space
    Orphan Used memory Free memory
    Large object space Code space
    Cell space
    Property cell space
    Map space
    Data space
    To-space From-space
    01
    03
    05
    07
    08
    09
    10
    (new object)
    

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11. Minor GC
    Heap memory
    New space (Young generation)
    Old generation
    (Old space)
    Pointer space
    Orphan Used memory Free memory
    Large object space Code space
    Cell space
    Property cell space
    Map space
    Data space
    To-space From-space
    01
    03
    05
    07
    08
    09
    10
    (new object)
    

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12. Minor GC
    Heap memory
    New space (Young generation)
    Old generation
    (Old space)
    Pointer space
    Orphan Used memory Free memory
    Large object space Code space
    Cell space
    Property cell space
    Map space
    Data space
    From-space To-space
    01
    05
    07 09
    10
    (new object)
    

    View Slide

13. Minor GC
    Heap memory
    New space (Young generation)
    Old generation
    (Old space)
    Pointer space
    Orphan Used memory Free memory
    Large object space Code space
    Cell space
    Property cell space
    Map space
    Data space
    From-space To-space
    01
    05
    07 09
    10
    (new object)
    

    View Slide