"Noons" <wizofoz2k_at_yahoo.com.au> wrote in message
news:42069396.30901_at_yahoo.com.au...
> > No I didn't say that. Transaction rollback does work with DB2 circular
logs.
>
> until it runs around the end of the log, eh?
>
If a single unit of work that has not committed uses up all the logs in a
circular logging scheme, then DB2 will stop processing any inserts, updates,
or deletes. You can make the circular logs quite large (and use secondary
allocations), but archive logging (log retain) is normally used in
production unless there is a decision support database with only loads and
selects.
>
> > You can allocate up to 2GB of memory for the DB2 locklist.
>
> and when that is all used up, the whole thing grinds to a halt.
> As I said: that is sooooooo scalable...
>
2 GB is about 250 million locks (the exact amount of memory needed depends
on whether it is the first lock on a row, subsequent lock on a row, or
whether you are using 32bit/64bit DB2 instance). When it runs out of memory,
then it changes to table locks, so if you allocated the maximum amount for
the locklist DB2 would not grind to a halt unless you had more than 250
million tables in your database.
Received on Sun Feb 06 2005 - 16:30:01 CST
