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From: Andy Parkins <andyparkins@gmail.com>
To: bitcoin-development@lists.sourceforge.net
Date: Fri, 31 May 2013 13:54:03 +0100
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Subject: Re: [Bitcoin-development] Implementing batch processing for
	-blocknotify
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On Friday 31 May 2013 12:56:43 Rune Kj=E6r Svendsen wrote:

> I have an application that wants to keep up with new blocks as they come
> in. For that I can use the -blocknotify option with bitcoind, which will
> execute my application for each new block.
>=20
> The problem is that my app isn't necessarily quick enough to finish its
> work before a new block comes in and the app is executed again. This means
> the that bitcoind might keep executing my application even though the
> previous instance hasn't finished, and that's fairly inefficient
> resource-wise, as many instances of the application will be running
> simultaneously.

Have your program try to create a unix-domain socket when it starts.  If it=
=20
can't create it (because one already exists at that path), then connect to =
it.

You then have two modes:

 - Creator of socket, listens to socket for more incoming data, and adds it=
 to
   some sort of internal block queue.
 - Client to socket, pushes output of -blocknotify to socket and exits

Your concurrency problems go away because only one process is ever actually=
=20
doing something with the data.

Should be fairly straight forward.  The client is simple.  The server is tw=
o=20
threads, one listening on the socket and then briefly locking and updating =
a=20
queue, and one thread briefly locking and removing from the queue.



Andy

=2D-=20
Dr Andy Parkins
andyparkins@gmail.com