Aerospike, a company dealing with high scalability issues, has found effective solutions to combat memory fragmentation using JEMalloc, a dynamic memory allocator. Memory management is crucial in computer architectures and can lead to performance degradation or memory leaks if not handled properly. JEMalloc provides fast allocation and deallocation of memory while minimizing fragmentation. Aerospike's implementation of JEMalloc optimized memory utilization, reduced fragmentation, and improved overall application performance in multi-threaded environments.