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Sweep interval


What does SWEEP INTERVAL do ?

My value is 20000 !
Would I benefit from changing it to something else ?
Security ?
Speed ?

Best Regards / Med venlig hilsen
Michael Vilhelmsen
Microcom ApS, Denmark


Re:Sweep interval

In article <Xns922A6CF3BE373MichaelVilhelmsen...@>,
Michael.Vilhelm...@Microcom.NoSpam.Com says...


> What does SWEEP INTERVAL do ?

        Controls how often IB sweeps.  :)

> My value is 20000 !

        This is the number of transactions between the oldest interesting
transaction (in IB 6, this is essentially the last rollback which
affected a large-ish number of records) and the next transaction (run
gstat to see these numbers) which must exist before IB sweeps (cleans up
old record versions no longer in use.

> Would I benefit from changing it to something else ?
> Security ?

        In IB 5.5, it was necessary to set the sweep interval to 0 as the
automatic sweep could corrupt the DB.  This was fixed in IB 5.6 and
hasn't been a problem since.

> Speed ?

        The sweep can negatively impact other connections, especially in
pre-V6 (in V6 it's less of a problem).  So, especially on earlier
versions of IB, you can squeeze a little extra performance out of IB by
setting the sweep interval to zero and manually starting the sweep
during off hours.

        But this is often more trouble than it's worth.  YMMV.



 Craig Stuntz (TeamB) Vertex Systems Corp. Columbus, OH
     Delphi/InterBase WebLog:
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Re:Sweep interval

If you do not understand Craig's answer you may want to read

Bill (TeamB)
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