Chunking and bundling

[Mike Rylander]

Configuring XMPP stanza size for OpenSRF can be confusing, and, in some cases, fraught with dangers. It's an opaque value unless you know most of the backend code, and tuning it is basically guess work until you run into a specific failure case.

So let's fix that! Here is offered a branch from early 2014 that Bill Erickson and I collaborated on that provides the following features:

 * OpenSRF message bundling -- Pack multiple OpenSRF messages together in a single XMPP envelope, as long as we believe more messages will be sent in the future and we are below some threshold of combined message size. The default for that threshold is 25Kb.

 * OpenSRF message chunking -- Break up large OpenSRF messages across multiple XMPP envelopes. This is implemented with a new OpenSRF message type. C, Perl, and Javascript libraries are taught how to reconstruct chunked messages. The default chunking threshold is 50Kb, just a bit below the default ejabberd max stanza size of 64Kb.

Branch to follow soon...

[Mike Rylander (mrylander)]

Here's the branch:

http://git.evergreen-ils.org/?p=working/OpenSRF.git;a=shortlog;h=refs/heads/collab/miker/bundling-and-chunking-rebase-aug12

[Galen Charlton (gmc)]

I've pushed a rebased version of the branch (along with some documentation improvements) to master for inclusion in 2-5-alpha. Thanks, Mike and Bill.