Hi, memory mapping is a decent solution as it will leave the caching (with frequent access) and other optimizations to the operating system. Multiple processes using the same memory-mapped file will also use the same in-memory cache. Gruß Johannes -- Johannes Dröge, M.Sc. Computational Biology, Helmholtz Centre for Infection Research, Braunschweig Algorithmic Bioinformatics, Heinrich Heine University, Düsseldorf PGP: http://keys.fungs.de/6ea5e4.asc (55F2720303A7F236A94666F20E2360727A6EA5E4) Web: algbio.cs.uni-duesseldorf.de | Tel/Fax: +49 211 81-12644/13464