Subject Re: [firebird-support] Firebird RAID Windows Server 2008 R2
Author Paul Vinkenoog
Hello Maarten,

> Is the possible unreliability on Windows only applicable in
> these cases (power loss/abnormal windows shutdown/freeze)?
> In that case async mode is acceptable, because we run a UPS.

That only protects you against power losses. But with forced writes
off, your mutations 'hang' in memory until the OS decides that it's
time to write them to disk. It may be seconds, minutes or more -
you simply don't know. For as long as the changes have not been
written to disk, the situation is 'unsafe'. Power losses and abnormal
shutdowns are rather dramatic examples, but other things can go wrong
too - with the buffer, with the scheduler - and cause failures, in
the worst case without you even noticing it.

So the advice is always: for any serious use, don't turn off forced
writes, except *temporarily* e.g. during mass data imports. After
such an event, check that everything has gone well.

It's tempting to speed up Firebird (or any app) as much as possible,
and if you're lucky it will never go wrong. But if it *does* go
wrong - was the performance gain worth it?

Paul Vinkenoog