I'm not looking for fairies :-) I was just curious exactly how mmap interacts with the OS in order to understand performance metrics better.
On Sat, Feb 6, 2016 at 5:46 PM, Howard Chu <[email protected]> wrote: > Kristoffer Sjögren wrote: >> >> Thanks Howard. What's the best documentation on mmap you know, aside >> from read kernel source code? > > > Not sure what you're asking. Read the mmap(2) manpage and its related pages. > If you're thinking there's something fancy hidden in there for you to take > advantage of, I don't think you should be using mmap in the first place. > > >> On Fri, Feb 5, 2016 at 10:33 PM, Howard Chu <[email protected]> wrote: >>> >>> Kristoffer Sjögren wrote: >>>> >>>> >>>> Hi >>>> >>>> Our application do lots of caching using vmtouch, up to a point where >>>> there isn't a lot of memory left on the machine. We would like to use >>>> LMDB on the same machine to store around 40GiB data of a few hundred >>>> million entries. >>>> >>>> How can we best understand the interaction and behavior of the OS >>>> cache and sharing of memory between processes? Is LMDB doing something >>>> to help the OS? >>> >>> >>> >>> Nope, LMDB does nothing special with its mmap. >>> >>> -- >>> -- Howard Chu >>> CTO, Symas Corp. http://www.symas.com >>> Director, Highland Sun http://highlandsun.com/hyc/ >>> Chief Architect, OpenLDAP http://www.openldap.org/project/ >> >> > > > -- > -- Howard Chu > CTO, Symas Corp. http://www.symas.com > Director, Highland Sun http://highlandsun.com/hyc/ > Chief Architect, OpenLDAP http://www.openldap.org/project/
