[Engine-devel] Default TransactionScope at engine

[Michael Kublin]

Hi All,

Today most of the flows of runAction at engine look like at the following way:

1. Perform some selects
2. Perform call to host (xml rpc) or call to some number of other actions in synchronous way 
3. If a call success than perform update to DB.

It is means that we actually need open transaction only at the step 3, it is mean that by default
we are keeping transaction much more longer than it should be, the call to host can take a while.

So, the possible plan of action is
1. Change a default scope of transaction from TransactionScopeOption.Required to TransactionScopeOption.Suppress
2. Remove annotation NonTransactiveCommandAttribute
3. The actions which are need to run in transaction - appropriate transaction scope should be passed via parameters 

It is a lot of dirty and not to interesting work, but I think it will provide a great benefit:
1. Reduced a time of open transaction 
2. Better db connection utilization
3. I think that number of open transaction will also reduce 
4. As a result performance will improve

By the way, many of new actions which are written today by default marked as NonTransactiveCommandAttribute, if we will continue
in such way almost every class will be marked with NonTransactiveCommandAttribute

Regards Michael