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PAGE SIZE OF THE DATABASE FILE

The meaning of the page size of database file relates to the structure of the database file Firebird® and stands for a single data block in the file. Database server during the read-out operation or data recording to the base file, operates on such data blocks. By increasing the size of the page of the database file, the volume of data read-out/saved by one operation increases simultaneously. By increasing the page size, a number of disc operations performed by the server is simultaneously reduced.

PAGE SIZE AND EFFICIENCY

From the version 2.0 of the Firebird® server, 4096 bytes is a default value of the size page.

Performance tests (run also in the RHO Software) showed that increasing of the page size of database file can improve the pace of performing some queries by 20% (according to other sources even to 30%). It relates mainly to the big data bases and big records.

Tests run in the RHO Software on the database of the Modus system showed that the biggest increase in efficiency was gained,when the size page of the file was equaled to 4096 or 8192. It can not be unambiguously said which value is more optimal, because it depends not only on the size of the whole data base, but also from the size of the individual records.

ZMIANA ROZMIARU STRONY W BAZIE SYSTEMU MODUS

Page size of the database file can be defined as only during one of the operations mentioned below:

  1. Creating a new database.
  2. Recording of the database from the file of the copy.

Począwszy od wersji 1.7.2 panelu administracyjnego ModusAdmin (instalowanego wraz z systemem Modus w wersji 1.17 i późniejszych) wprowadzono możliwość określenia rozmiaru strony pliku bazy danych. Opcja jest dostępna w panelu administracyjnym na zakładce Ustawienia. Aby zmienić rozmiar strony bazy danych należy wybrać określoną wartość i wcisnąć przycisk Zapisz ustawienia.

Remember, that the change of this option's value does not update the page size of the on-line database and will be used only at the moment of reproducing database from the backup.
The quickest way of the change of page size in the database is by using the function optimization of the database that makes a copy of the base, and reproduce the base from this copy.

Read also: Backups * Optimization of the database

MORE ON THIS TOPIC

The database file page is also connected with other technical issues, e.g. a depth of index cards, a size of the server's memory cache or the volume of the hard disc's cluster. Appropriate information can be found in the widely-available documentation of the Firebird's® derver.