IBM 000-8697 Manual Do Utilizador

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IBM Informix OnLine Database Server Administrator’s Guide
Things to Avoid
From the Command Line
1.
To change the value of
 CLEANERS
 from the command line, use an
editor to edit the file specified by $
INFORMIXDIR
/etc/$
TBCONFIG
.
2.
Change the value of
 CLEANERS
. Reinitialize shared memory (take
OnLine offline and then to quiescent mode) for the change to take
effect.
Things to Avoid
Here are some ideas that might sound good in theory, but have unexpected
consequences that could adversely affect your OnLine performance. Below is
a list of things to avoid:
Never kill an OnLine database server process during database
activity. Check that the server process is not holding a latch and is not
in a critical section. Use tbmode -z to end a database server process.
Refer to
.
Avoid transactions that span a significant percentage of available
logical log space.
Do not define your archive tape device (
TAPEDEV
) as a named pipe.
Do not rely on dbexport (a utility that creates a copy of your database
for migrating) as an alternative to creating routine archives.
Do not run utilities that send output to tape in background mode
(using the & operator).
Do not switch the logical log tape device between a tape device and
/dev/null
 while the logical log files are in use.