status of gcj's boehm collector?

Bryce McKinlay bryce@waitaki.otago.ac.nz
Tue Dec 4 16:29:00 GMT 2001


Adam Megacz wrote:

>>2) On a platform like Linux modified page information is kept by write
>>protecting pages and catching write faults.  This works fine if the page is
>>modified as the result of an instruction executed by the user program.  It
>>causes problems if the write occurs as the result of a system call.  Thus
>>system calls must be suitably protected.  There are some hooks in the GC
>>library to do this, but libgcj doesn't.  Furthermore, those hooks currently
>>have problems in multithreaded environments with blocking system calls.
>>
>
>Okay, so this means that incremental GC isn't likely to happen.
>

I don't think its unfixable, and I would certainly like to see an 
incremental (or concurrent?) option in the future. But clearly the 
tradeoff is between overall throughput and reduced latency/pause times, 
so its only a win for interactive applications, which gcj doesn't really 
support. Yet.

>I think I can live with that. How about generational GC?
>

I think that with the boehm-gc, one implies the other.

regards

Bryce.




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