09.05.2018 17:15, liviuslivius wrote: > >> No, caching is left up to OS. > > i do not understand above. I have dissabled os caching in firebird.conf. > Also file is created by Firebird not OS. Can you explain this more?
You've disabled file-level caching for the database file, but this setting doesn't affect temporary files. While they're created by Firebird, Windows is asked to aggressively cache them if possible: Quoting MSDN: "Specifying the FILE_ATTRIBUTE_TEMPORARY attribute causes file systems to avoid writing data back to mass storage if sufficient cache memory is available, because an application deletes a temporary file after a handle is closed. In that case, the system can entirely avoid writing the data. Although it does not directly control data caching in the same way as the previously mentioned flags, the FILE_ATTRIBUTE_TEMPORARY attribute does tell the system to hold as much as possible in the system cache without writing and therefore may be of concern for certain applications." There's no such a hint on Linux though, the default file-caching policy is used there. To ensure in-memory storage, TempDirectories may be tuned to redirect writes to tmpfs, for example. Dmitry