liblmdb0 0.9.21-1ubuntu0.1 (s390x binary) in ubuntu bionic

 This package contains the LMDB shared library.
 .
 Lighting Memory-Mapped Database (LMDB) is an ultra-fast, ultra-compact
 key-value embedded data store developed for the OpenLDAP Project. It uses
 memory-mapped files, so it has the read performance of a pure in-memory
 database while still offering the persistence of standard disk-based
 databases, and is only limited to the size of the virtual address space, (it
 is not limited to the size of physical RAM).