Добавил:
Upload Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз: Предмет: Файл:
Скачиваний:
29
Добавлен:
18.03.2015
Размер:
684.09 Кб
Скачать

Global Improvements in Firebird 2.1

Instant Fix for an Older Firebird

Here's a tip if you want to do an instant fix for the problem in an older version of Firebird: use the “sync” option when mounting any partition with a Firebird database on board. An example of a line in /etc/fstab:

/dev/sda9 /usr/database ext3 noatime,sync 1 2

Databases on Raw Devices

A. Peshkov

File system I/O can degrade performance severely when a database in Forced Writes mode grows rapidly. On Linux, which lacks the appropriate system calls to grow the database efficiently, performance with Forced Writes can be as much as three times slower than with asynchronous writes.

When such conditions prevail, performance may be greatly enhanced by bypassing the file system entirely and restoring the database directly to a raw device. A Firebird database can be recreated on any type of block device.

Moving a Database to a Raw Device

Moving your database to a raw device can be as simple as restoring a backup directly to an unformatted partition in the local storage system. For example,

gbak -c my.fbk /dev/sda7

will restore your database on the third logical disk in the extended partition of your first SCSI or SATA hard-drive (disk0).

Note

The database does not have a “database name” other than the device name itself. In the example given, the name of the database is '/dev/sda7'.

Special Issues for nbak/nbackup

The physical backup utility nbackup must be supplied with an explicit file path and name for its difference file, in order to avoid this file being written into the /dev/ directory. You can achieve this with the following statement, using isql:

# isql /dev/sda7

20

Тут вы можете оставить комментарий к выбранному абзацу или сообщить об ошибке.

Оставленные комментарии видны всем.

Соседние файлы в папке doc