>>> I also read through
>>> http://www.firebirdsql.org/manual/gfix-housekeeping.html once again. It
>>> seems to say that GC only happens on a full table scan, e.g. select
>>> count(*). I thought GC happens on a page by page basis, as each
>>> individual page is accessed.
>>
>> I even think it works on a per-record basis removing old record
>> versions, which aren't used/needed by other transactions anymore.
>>
>>> Can access to only small portions of a large table trigger GC on the
>>> entire table?
>>
>> I'm not sure, but I would say no.
>>
>> I would try the trace route to see exactly what's going on in the
>> database statement wise.
>
> Yes, I will probably do that as soon as possible.
>
>> Btw, any suspicious things in the monitoring tables at the time things
>> get hooked up?
>
> I'm not very familiar with them. Any ideas what I should be looking for?

E.g. MON$STATEMENTS to get the current statements.

Try the following product, which is entirely based on working with the
monitoring tables:
http://www.sinatica.com



--
With regards,

Thomas Steinmaurer
Upscene Productions
http://www.upscene.com
http://blog.upscene.com/thomas/

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