Sybase Adaptive Server IQ 12.4.2, Administration And Performance Manual

Page: 448 / 536

Overview of memory use
428
Setting buffer cache size database options
To set buffer cache sizes permanently (that is, until you explicitly reset them)
use the
SET OPTION
statement. Follow the procedure below.
❖
To change the buffer cache sizes permanently:
1 If the database whose cache sizes you are changing is not already started,
start it now:
START DATABASE dbfile [AS dbname] [ON engine_name]
2 Set one or both cache sizes.
• To set the buffer cache size for the IQ Store (the main buffer cache)
use the following syntax:
SET OPTION "PUBLIC".MAIN_CACHE_MEMORY_MB =
#_of_MB
• To set the buffer cache size for the Temporary Store (the temp buffer
cache) use the following syntax:
SET OPTION "PUBLIC".TEMP_CACHE_MEMORY_MB =
#_of_MB
-iqmc
and
-iqtc
server
switches
Reset cache sizes when
the database is not
running. Especially useful
if cache sizes are larger
than your system can
accommodate. From the time the server is
started until it is stopped “Setting buffer cache
size server switches” on
page 429
-iqsmem
and
-iqwmem
server switches
Use on some UNIX
platforms to provide
additional memory for use
as buffer caches. From the time the server is
started until it is stopped “Platform-specific
memory options” on
page 434
LOAD_MEMORY_MB
database option
Indirectly affects buffer
cache size, by controlling
the memory that can be
used for loads. On some
platforms, allowing
unlimited memory for
loads means less memory
is available for buffer
caches. Immediately until you reset
the option “Memory for loads,
synchronizations, and
deletions” on page 421
Method When to use it
How long the setting is
effective For more
information, see