Christoph Lameter wrote: > On Wed, 24 Jan 2007, Erik Andersen wrote: > >> It would be far more useful if an application could hint to the >> pagecache as to which files are and which files as not worth >> caching, especially when the application knows a priori that data >> from a particular file will or will not ever be reused. > > It can give such hints via madvise(2).
I think you meant fadvise. That is certainly a possibility which we need to work on. Current implementation of fadvise only throttles read ahead in case of sequential access and flushes the file in case of DONTNEED. We leave it at default for NOREUSE. In case of DONTNEED and NOREUSE, we need to limit the pages used for page cache and also reclaim them as soon as possible. Interaction of mmap() and fadvise is little more dfficult to handle. --Vaidy > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to [EMAIL PROTECTED] > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
