Supongo que en algún momento harás un "commit" de todas las transacciones.
Supongo que tendrás "write sync"
Cita:
Many operating systems employ a disc cache mechanism. This uses an area of memory (which may be part
of your server's overall RAM or may be built into the disc hardware) to buffer writes to the hardware. This
improves the performance of applications that are write intensive but means that the user is never certain when
their data has actually been written to the physical disc.
With a database application, it is highly desirable to have the data secured as soon as possible. Using Firebird,
it is possible to specify whether the data should be physically written to disc on a
COMMIT
or simply left to the
operating system to write the data
when it gets around to it
.
To give the DBA or database owner full control of when data is written, the
gfix -w[rite]
command can be used.
The command takes two parameters:
gfix -write MODE database_nam
The MODE parameter specifies whether data would be written immediately or later, and is one of:•
sync
- data is written synchronously. This means that data is flushed to disc on
COMMIT
. This is safest
for your data.
•
async
- data is written asynchronously. The operating system controls when the data is actually written to
disc.
If your system is highly robust, and protected by a reliable UPS (uninterruptable Power Supply) then it is possible
to run asynchronously but for most systems, synchronous running is safest this will help prevent corruption in
the event of a power outage or other uncontrolled shutdown of the server and/or database
Firebird defaults to synchronous mode (forced writes enabled) on Linux, Windows NT, XP, 2000, 2003 and
Vista.
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