Re: status of gcj's boehm collector?

[Bryce McKinlay <bryce at waitaki dot otago dot ac dot nz>]

Adam Megacz wrote:

>I still think System.gc() has the right connotations, since it is not
>a thread-specific operation. Would you approve of using it if there
>was a way for the appliation to know how much allocation had taken
>place since the last full heap scan?
>
>If not, what would you suggest instead of System.gc()?
>

Ideally, there shouldn't be any reason to ever want to trigger an 
explicit collection.

Event driven applications, such as a GUI application or a webserver, 
tend to spend much of their time sitting around doing nothing, but they 
need to respond as quickly as possible when an event does arrive. So for 
this type of application, the worst time to perform a GC is arguably 
during a "new", and the best time is while other threads are idle.

If we can get incremental mode working reasonably, it ought to be then 
possible to run most of the GC in a separate thread, without "stopping 
the world". This way the GC could do its work while other threads are 
idle and latency would be very low. If the GC can't keep up with the 
mutators then I guess it would still need to stop the world to complete 
a collection, but that hopefully wouldn't be common with typical 
applications.

regards

Bryce.