Subject RE: [Firebird-Architect] WAL and JOURNAL
Author Leyne, Sean

> So we're clear about the fact that those slave would be guaranteed to
> be read-only beasts : only accepting read-only transactions or another
> mechanism to guarantee those slaves are read-only ?

There will be a mechanism which will ensure that the slave will be

> Are we sure those uncommitted changes eventually physically present on
> the slave pages could not interact badly with running queries ?

That's what we'll find out as Nickolay and I develop the solution.

(Actually, Nickolay will be the one developing, I will supervise from
the comfort of my regal chair ;-])

> If I start a "long-running" query in a default read-only transaction
> (concurrency) on a slave, and new page updates come in from master
> with new committed transactions, how this will work ? I should need to
> see the old records that might well not exists anymore in the recent
> pages. I'm not sure I'm not lost in the thing, but I fear some issue
> here.

Glad to see that you're keeping up with the scope of the problem ;-)

Yes, these issues will need to be considered.