Summary information |
|
|---|---|
Default value |
0 (off) |
Range of values |
0 (off), 1 (on) |
Status |
Dynamic |
Display level |
Basic |
Required role |
System administrator |
Configuration groups |
Memory Use, Physical Memory |
allocate max shared memory determines whether Adaptive Server allocates all the memory specified by max memory at start-up or only the amount of memory the configuration parameter requires.
By setting allocate max shared memory to 0, you ensure that Adaptive Server uses only the amount of shared memory required by the current configuration, and allocates only the amount of memory required by the configuration parameters at start-up, which is a smaller value than max memory.
If you set allocate max shared memory to 1, Adaptive Server allocates all the memory specified by max memory at start-up. If you set allocate max shared memory to 1, and if you increase max memory, Adaptive Server attempts to allocate the memory immediately. If the memory allocation fails, Adaptive Server writes messages to the error log. Check the error log to verify that no errors have occurred.
A successful memory allocation means that Adaptive Server always has the memory required for any memory configuration changes you make and there is no performance degradation while the server readjusts for additional memory. However, if you do not predict memory growth accurately, and max memory is set to a large value, you may waste total physical memory.
