Subject Re: [IB-Architect] Re: [IB-Priorities] Isolation level implemetation
Author Jim Starkey
At 09:10 PM 12/27/00 -0500, Andy Lewis wrote:
>I supose the objectives of the project should really control the
>criteria for adding features - my opinions may not be well aligned with
>that :)
>Let me preface this by stating that I don't know the architecture of IB
>well enough yet to know if the lower isolation levels actually impact
>performance significantly or not, but it does on most databases.

That's an important point. Interbase was designed so the cost of
transaction control was negligable. The multi-version crud happens
in lieu of a transacation log, and is essentially free. The minor
cost for read-only transactions chasing down the odd old version
isn't worth losing sleep over. Getting dumb isn't going to speed
anything up.

> How much transaction control do you need on 10,000 SELECT
>statements to keep them from causing problems with each other?

None, which is what Firebird does. Unlike the other guys,
Firebird doesn't have the equivalent of read locks.

There is
>a point where a transaction simply doens't get any less expensive, and
>as volume goes up, every little bit counts.

Jim Starkey