Thanks for your reply Ann...please see below your comments:

> Very odd. Could you collect the performance stats for the query on the two systems? >Specifically, I'd like to know how much physical I/O each did - that's reported as Reads >and Writes. Fetches and Marks don't matter here.

This is what I did:

# /opt/firebird/bin/gfix -buffers 100000 -user SYSDBA -password
XXXXXX /sis/arodat/test.fdb
# /etc/ini.d/firebird restart

1) select count(*) from TABLE1 with pagebuffers=100000 on the database:
mon$page_reads=305093
mon$page_writes=0
execution time=51min

# /opt/firebird/bin/gfix -buffers 0 -user SYSDBA -password XXXXXX
/sis/arodat/test.fdb
# /etc/ini.d/firebird restart

2) select count(*) from TABLE1 with pagebuffers=0 on the database:
mon$page_reads=305187
mon$page_writes=0
execution time=1sec


Now I'm getting mad...second execution took only 1 sec...this is
certainly due to cache use but if I restarted firebird server process,
does it keep cache?

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