Fengguang Wu <[EMAIL PROTECTED]> writes: > OVERHEADS > > The new code reduced the overheads of > > - excessively calling the readahead routine on small sized reads > (the current readahead code insists on seeing all requests) > > - doing a lot of pointless page-cache lookups for small cached files > (the current readahead only turns itself off after 256 cache hits, > unfortunately most files are < 1MB, so never see that chance)
Would it make sense to keep track in the AS if the file is completely in cache? Then you could probably avoid a lot of these lookups for small in cache files > --- linux-2.6.21-rc7-mm1.orig/mm/readahead.c > +++ linux-2.6.21-rc7-mm1/mm/readahead.c > @@ -733,6 +733,11 @@ unsigned long max_sane_readahead(unsigne Quite simple patch, why is it that much simpler than your earlier patchkits? Or is that on top of them? You seem to have a lot of magic numbers. They probably all need symbols and explanations. Your white space also needs some work. -Andi - 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/
