Maximum memory used by the process. The default value is 8GiB. When specified without a unit, MiB is assumed. This parameter does not change the memory allocation of the program. Rather, it sets a hard limit beyond which the process will kill itself and be restarted. The default value of 8GiB is double the intended memory usage in the default configuration (providing an emergency buffer to deal with memory leaks or similar problems). It is not recommended to decrease the value of this parameter below its default value. It may be increased if you wish to allocate a very large amount of storage engine memory or cache. In particular, when the storageMemory parameter is increased, the memory parameter should be increased by an equal amount.
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