I am testing FB's performance on large database (>4GB). I found that
the speed of the first query after reboot is substantially slower
(around 5 seconds) than normal even though it is a simple query on
index. I then disable the Windows cache in firebird.conf and the
performance is consistently slow (~5 seconds). So the slow performance
after reboot is likely to be due to the windows cache.

While it is understandable that windows cache can impove performance, I
am amazed at the degree firebird depends on Windows cache. I have
conducted a similar test (same data, same query) on postgresql and its
speed after reboot is very fast.

Is there anything to do with the fundamental design of FB?

Pokka