> gstat output (normal performance):
> ---------------------------------------------------------

>  Oldest transaction 18709808
>  Oldest active  18953295
>  Oldest snapshot  18851591
>  Next transaction 19520857

The large difference in Oldest Active and Next Transaction suggests that your problem is with garbage collection which is creating a growing backlog of pages that need to be read to find the correct record versions.

You have a process which is not committing transactions which you need to find, using the MON$Transactions and MON$Attachments tables.


Sean