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Java theory and practice: Plugging memory leaks with weak references

Weak references make it easy to express object lifecycle


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Listing 3. HPROF output showing growth in Map.Entry and Task objects

SITES BEGIN (ordered by live bytes) Fri Oct 28 16:30:48 2005
          percent          live          alloc'ed  stack class
 rank   self  accum     bytes objs     bytes  objs trace name
    1 70.13% 70.13%   5694888 13909   5694888 13909 300305 int[]
    2 18.27% 88.40%   1483976   68 278273632 13908 300321 int[]
    3  4.11% 92.51%    333816 13909    333816 13909 300310 java.util.HashMap$Entry
    4  2.74% 95.25%    222544 13909    222544 13909 300304 com.quiotix.dummy.MapLeaker$Task
    5  2.42% 97.67%    196640    2    262192    11 300325 java.util.HashMap$Entry[]
    6  0.66% 98.33%     53680 3355    222464 13904 300324 java.util.concurrent.LinkedBlockingQueue$Node
SITES END

SITES BEGIN (ordered by live bytes) Fri Oct 28 16:31:32 2005
          percent          live          alloc'ed  stack class
 rank   self  accum     bytes objs     bytes  objs trace name
    1 77.07% 77.07%  41176024 100020  41176024 100020 301069 int[]
    2 12.98% 90.05%   6933768  359 2001885688 100020 301093 int[]
    3  4.49% 94.55%   2400480 100020   2400480 100020 301082 java.util.HashMap$Entry
    4  3.00% 97.54%   1600320 100020   1600320 100020 301068 com.quiotix.dummy.MapLeaker$Task
    5  1.96% 99.50%   1048592    1   2097248    14 301104 java.util.HashMap$Entry[]
    6  0.05% 99.55%     25936 1621   1600240 100015 301101 java.util.concurrent.LinkedBlockingQueue$Node
SITES END


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