In this way, MMAP and DBMSs are like coffee and spicy food: an unfortunate combination that becomes obvious after the fact.

Since developers keep trying to use MMAP in new DBMSs, we wrote this paper to provide a warning to others that MMAP is not a suitable replacement for a traditional buffer pool. We discuss the main shortcomings of MMAP in detail, and our experimental analysis demonstrates clear performance limitations. Based on these findings, we conclude with a prescription for when DBMS developers might consider using MMAP for file I/O.