Have been testing the new version of our application on a server and have been impressed by quick responses. The server team did some work on the server and restarted it. Suddenly my application performance was terrible. Initially, I blamed the server team but later found that, when the server is restarted, the cache is cleared. This clearing caused the performance issues as all the records must be read from disk.

When the server is put into production we will have the same issue as the Relational and Transaction Engines are closed before backup to ensure that no files are locked for backup however this also closes the cache.

The software vendor is looking into the PSQL Backup Agent where "open" files can be backed up.

I'm wondering how other uses of PSQL manage backups and open files and is it really an issue?