setMaxMemSize

setMaxMemSize(memSizeGB, [emergencyMemSizeGB])

memSizeGB is a numeric scalar (in GB). It is greater than 0 but no greater than maxMemoryPerNode (specified by DolphinDB license), which can be checked with function license. Otherwise an error will be raised.

emergencyMemSizeGB(optional) is a numeric scalar (in GB) used to dynamically modify the size of the emergency memory area. It must be greater than 0 and less than 50% memSizeGB. It must be at least 256 MB and no more than 5 GB. If not specified, the value remains unchanged from the emergencyMemSize configuration parameter.

Modify the maximum memory and emergency memory allocated to DolphinDB online. This command can only be executed by the administrator. Call getClusterPerf().maxMemSize to check if the modification on maximum memory has taken effect.

When dynamically adjusting the maximum memory space (the corresponding configuration parameter is maxMemSize), if the user does not specify other settings, the system will automatically adjust the sizes of the reserved memory area (reservedMemSize) and the emergency memory area (emergencyMemSize) as follows:

• reservedMemSize will be set to 5% of the provided memSizeGB, with a minimum of 64 MB and a maximum of 1 GB.
• emergencyMemSize (if not explicitly set) will be set to 5% of memSizeGB, with a minimum of 256 MB and a maximum of 5 GB.

For more information on DolphinDB memory management configuration parameters and strategies, refer to the Reference - Memory Management.