Sybase Adaptive Server IQ 12.4.2, Administration And Performance Manual

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Balancing I/O
446
To move or rename the transaction log file, use the Transaction Log utility
(
DBLOG
). For syntax and details, see “The DBLOG command-line utility” on
page 405.
Warning! The Adaptive Server IQ transaction log file is different than most
relational database transaction log files. If for some reason you lose your
database files, then you lose your database (unless it's the log file that is lost).
However, if you have an appropriate backup, then you can reload the database.
The message log
A message log file exists for each database. The default name of this file is
dbname.iqmsg, although you can specify a different name when you create the
database. The message log file is actually created when the first user connects
to a database.
By default, Adaptive Server IQ logs all messages in the message log file,
including error, status, and insert notification messages. You can turn off
notification messages in the
LOAD
and
INSERT
statements.
Strategic file locations
Performance related to randomly accessed files can be improved by increasing
the number of disk drives devoted to those files, and therefore, the number of
operations per second performed against those files. Random files include
those for the IQ Store, the Temporary Store, the Catalog Store, programs
(including the IQ executables, user and stored procedures, and applications),
and operating system files.
Conversely, performance related to sequentially accessed files can be
improved by locating these files on dedicated disk drives, thereby eliminating
contention from other processes. Sequential files include the transaction log
and message log files.