Subject RE: [ib-support] When do FB/IB 'flush' to disk?
Author Leyne, Sean
Phil,

> We have an app that is constantly importing data to a
> database, an although
> we are commiting every couple of thousand records, the *.gdb
> file size never
> increases until we close the apps database connection. This
> leads to a GDB
> file(s) that has 500Mb of data in it to only be 3Mb in size.

In the case of Forced Writes = OFF, the OS is asked to write the
database information, but in it's own time (known as 'lazy writes').
It's *never* the case that the write is not requested by IB -- it's just
that with Forced Writes = ON, the engine forces the OS to write
immediately and waits to the operation to complete.

Windows, however, does not keep the filesize (as you would see it in
Explorer) updated. This is really more of a Windows 'display glitch'
than an IB/FB problem.

Equally, if your database and the server were to go *idle* for a little
while and then the server 'die', I would expect that the database would
be un-affected/recoverable since the OS would have flushed the pending
write operations.


Sean