On Thu, Jan 26, 2012 at 11:25:56AM -0500, Vivek Goyal wrote: > On Wed, Jan 25, 2012 at 02:35:52PM +0800, Wu Fengguang wrote: > > > It would also be > > > possible to trigger on the size of the device so that the 32MB USB stick > > > doesn't sit busy for a minute with readahead that is useless. > > > > Yeah, I do have a patch for shrinking readahead size based on device size. > > Should it be a udev rule to change read_ahead_kb on device based on device > size, instead of a kernel patch? That's effectively what vendors like SGI have been doing since udev was first introduced, though more often the rules are based on device type rather than size. e.g. a 64GB device might be a USB flash drive now, but a 40GB device might be a really fast SSD.... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
