This question is a rephrasing of Optimizing EXT4 performance.

I have a directory that contains build files, most very small, but totaling 5.6G.

I usually access the same subset of files (some thousands, for some tens of megabytes) over and over again. The subset changes daily (different projects, different versions of libraries). What takes longer when I use it seem to be disk seeks. For example if I do a du twice the second time it takes as much time as the first, and disk activity is similar.

Ideally I'd like to tell the kernel to allocate X Mb to the metadata and Y to data in the folder, like the options for nfs cache.

Is it possible in some way, other than mounting nfs from localhost and caching it to a ramdisk?