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From Kevin Burton <bur...@spinn3r.com>
Subject Advice for Scheduler refactor.
Date Sat, 02 May 2015 23:41:16 GMT
Wanted some feedback on this.

https://gist.github.com/burtonator/34a67c24ca9ce0574c04

I think I want to refactor the cancel method…

it calls purge() which is VERY expensive on large numbers of queues. N^2
expensive.

once the cancel() is called, the timer task won’t get executed, HOWEVER
there’s still a reference to the Runnable.  This is why I think purge() is
called.  This allows GC to kick in and remove the runnable without waiting
for the timer to fire.  Which I think is just 30 seconds later but not sure.

So I think the workaround here is to not to submit the Runnable itself but
a WeakRunnable and then, once we read the TimerTask, we just set the
reference to the underlying runnable to null.  This will allow GC and we
also don’t have to call purge().

Ps.  There are some other things that should be cleaned up here.  Probably
removing synchronized and using ConcurrentHashMap and also probably
ditching Timer and moving to Executors.. but that’s another project in and
of itself and might introduce bugs for no win.

Kevin

-- 

Founder/CEO Spinn3r.com
Location: *San Francisco, CA*
blog: http://burtonator.wordpress.com
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