Re: Db pool [was: My little comments to CPP code]

[sergey@total-knowledge.com]

> I meant for ThreadPool to be only an example on how CWaiters can be used,
> not as reference in implementation of database pool design. They are
> different
> in many ways (one of them - threads actually do something themselves,
> while
> database connections only have operations performed on them by those who
> request them.)
>
> Again - a pencil and a piece of paper, with little drawing of who does
> what
> might help you. The line in a super-market analogy can work fairly well,
> if you map
> your objects properly.

So here is the case when getConnection() is called, but maxCon limit has
been reached.

1. Check if there is an available connection in the pool, if yes, return it.
2. If no available connection, then wait 'timeout' milliseconds.
3. If connection is released, CWaiter sends a signal from
releaseConnection() to notify getConnection() that there is an available
connection.
4. If 'timeout' is over, return null. Otherwise call getConnection() again.


>
> --
> Ilya A. Volynets-Evenbakh
> Total Knowledge. CTO
> http://www.total-knowledge.com
>
>