Michael Schnell wrote: > >In my particular case kernel uses all available RAM (~10MB) for disk > >cache and releases it only in ~15 seconds. Other applications cannot > >be started if one reads large files from disk. I do not experience > >this problem with 2.4.17 kernel. > > > AFAIK, the Kernel _should_ reduce the disk cache as soon as memory is > needed for other purposes (e.g. starting an application). Of course this > might take some time for writing back the uncommitted blocks, but of > course _much_ less than 15 seconds.
It's all clean data; there is nothing to write back. It's a common misconception that "free space is wasted space", so it's ok to fill all the memory with clean page cache. It comes from the fact that actually it _is_ good with an MMU, but causes insurmountable fragmentation problems without an MMU. > AFAIK, there are several settable (maybe when compiling, maybe at run > time) parameters that define the disk cache behavior. Did you take a > look at those ? Certainly, on 2.4, you cannot find suitable settings in a standard 2.4 kernel. Only the patched uClinux 2.4 kernel works, and I had to patch it some more. -- Jamie _______________________________________________ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
