sum of dynamic memory usage of all the map elements (NOT the maps themselves)
Declared in <txmempool.h>
[[guarded_by(0x7fd7537b8248), guarded_by(0x7fd74eec4bd8), guarded_by(0x7fd75e706228), guarded_by(0x7fd7598929f8), guarded_by(0x7fd75ce049c8), guarded_by(0x7fd759f6de58), guarded_by(0x7fd75b82e098), guarded_by(0x7fd73e8ac2f8)]]
uint64_t cachedInnerUsage = {0};