Distributed Data Management

 For Data Synchronization inside Caché you have a range of ways to synchronize objects and tables.
At DB level you can use Shadowing  or Mirroring 

This works excellent and if you need just a part of your data to be synchronized you may split your
data into smaller pieces using Global mapping 
Or if you need bi-directional synchronization on Class/Table level you can use the Object Synchronization Feature 

The limit of all these excellent features:
They just work from Caché/IRIS to Caché/IRIS.

Several years ago everyone got mad about BigData – nobody knew when smallish data will become BIGDATA, but all knows that it’s trendy and the way to go.

The technology of load balancing between several servers with relatively low capacity has been a standard feature of Caché for quite a while. It is based on the distributed cache technology called ECP (Enterprise Cache Protocol). ECP provides a host of possibilities for horizontal scaling of an application, and yet keeping the project budget fairly low. Another apparent advantage of ECP network is the possibility to conceal its architecture in the depths of Caché configuration so that applications developed for the traditional (vertical) architecture can be fairly easily migrated to a horizontal ECP environment. The ease of this process is so mesmerizing, that you start wishing it was always this way. For instance, everybody is used to having a possibility to control Caché processes: the $Job system variable and associated classes/functions work magic in skilful hands. Stop, but now processes can end up being on different Caché servers…

This article is about how to gain as much transparency in controlling processes in ECP environment as in traditional (non ECP) one.

Good day

Additional tool for MUMPS servers MiniM InterConnect:

http://www.minimdb.com/tools/interconnect.html

to connect job on one MUMPS server to other job on other MUMPS server in client-server mode. This tool can connect different MUMPS systems on different OS and with different processors - MiniM, Cache and GT.M in any pairs.

Regards,

Eugene Karataev

Consider a design where there could be three or four or more servers and there is a need to have these eventually consistent between them all (and not considering database mirroring here).