Which drive has my file ? and other DP for dummies questions..

[ytulpan]

1. Is there a simple method to know where DP keeps a specific file ?

Say an application opens a file for write while that file is being moved by a rebalancer. What will happen ?

Similarly, say a file is kept continuously open (i.e. a database file). Will it be rebalanced ? How ? What about duplication ?

[Alex]

1. Unfortunately not yet, but it's on the todo list and we'll add it eventually.
2. As soon as that file is opened, the balancer aborts and rolls back whatever it was doing, and the application proceeds to open the file as if nothing else had the file open. The application never gets an error.
3. Background duplication / rebalancing cannot move files that are in use. However, background duplication typically only runs when changing the duplication level of existing files.

    

   Once the duplication level change is complete, any further real-time changes to those files are simply written to all file parts at the same time. This means that once background duplication completes you don't have to worry about files that are in use.

[ytulpan]

Thank you Alex,

 

This was a very clear explanation.

 

Complex product. Just looks simple from the outside.

[Christopher (Drashna)]

Amen to that.

 

Yeah, there are a lot of moving parts, and a lot that happens behind the scenes. And Alex has done an extraordinary job making it all look simple and making it easy to use.