Subject Re: [firebird-support] Oldest transaction stuck
Author Thomas Steinmaurer

> On Aug 18, 2011, at 12:45 PM, "Bob Murdoch"<mailgroups@...> wrote:
>> I have an FB 2.1.2 classic installation running a 70GB database ... I just
>> discovered last week that gbak was being run without garbage
>> collection (-g), probably to speed up the backup process. This led to
>> a gap between OAT and OIT that was just huge.
>> I successfully ran gbak with garbage collection (that took 48 hours).
>> However, the transaction stats on the database do not seem to have
>> been cleared up:
>> Database header page information:
>> Oldest transaction 12778
>> Oldest active 24126761
>> Oldest snapshot 24126761
>> Next transaction 24152614
>> My understanding was that I do not need to run a manual sweep if I am
>> running gbak each night (with garbage collection enabled, of course).
>> The question is, do I need to run a sweep on this DB, or is there
>> something else that is preventing the OIT from advancing?
> Don't worry about it. Oldest active is a problem, and OIT was a problem with classic on small memory systems that have been gone for a decade. If it bothers you, run a sweep after a garbage collectung backup

So you say that a gap OAT-OIT of 24 mio in this case doesn't harm server
performance? I thought, each transaction start has to read the TIP pages
starting from the OIT to the OAT, which is quite a number here.


With regards,

Thomas Steinmaurer
Upscene Productions

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