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42 lines
1.8 KiB
Plaintext
42 lines
1.8 KiB
Plaintext
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Performance of the incremental collector can be greatly enhanced with
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-DNO_EXECUTE_PERMISSION.
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The collector should run with all of the -32, -n32 and -64 ABIs. Remember to
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define the AS macro in the Makefile to be "as -64", or "as -n32".
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If you use -DREDIRECT_MALLOC=GC_malloc with C++ code, your code should make
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at least one explicit call to malloc instead of new to ensure that the proper
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version of malloc is linked in.
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Sproc threads are not supported in this version, though there may exist other
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ports.
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Pthreads support is provided. This requires that:
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1) You compile the collector with -DGC_IRIX_THREADS specified in the Makefile.
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2) You have the latest pthreads patches installed.
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(Though the collector makes only documented pthread calls,
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it relies on signal/threads interactions working just right in ways
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that are not required by the standard. It is unlikely that this code
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will run on other pthreads platforms. But please tell me if it does.)
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3) Every file that makes thread calls should define IRIX_THREADS and then
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include gc.h. Gc.h redefines some of the pthread primitives as macros which
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also provide the collector with information it requires.
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4) pthread_cond_wait and pthread_cond_timed_wait should be prepared for
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premature wakeups. (I believe the pthreads and realted standards require this
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anyway. Irix pthreads often terminate a wait if a signal arrives.
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The garbage collector uses signals to stop threads.)
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5) It is expensive to stop a thread waiting in IO at the time the request is
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initiated. Applications with many such threads may not exhibit acceptable
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performance with the collector. (Increasing the heap size may help.)
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6) The collector should not be compiled with -DREDIRECT_MALLOC. This
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confuses some library calls made by the pthreads implementation, which
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expect the standard malloc.
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