On Tue, Oct 23, 2012 at 09:41:00AM -0400, Rik van Riel wrote: > On 10/23/2012 01:51 AM, Shaohua Li wrote: > > >I have no strong point against the global state method. But I'd agree making > >the > >heuristic simple is preferred currently. I'm happy about the patch if the > >'+1' > >is removed. > > Without the +1, how will you figure out when to re-enable readahead?
Below code in swapin_nr_pages can recover it. + if (offset == prev_offset + 1 || offset == prev_offset - 1) + pages <<= 1; Not perfect, but should work in some sort. This reminds me to think if pagereadahead flag is really required, hit in swap cache is a more reliable way to count readahead hit, and as Hugh mentioned, swap isn't vma bound. Thanks, Shaohua -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
