//
// Some read activity through the buffer cache and the cache read
// hit ratio is less than 80%
// (lots of file system reads causing physical I/O)
//

delta = 1 min;			// check every minute

blkio = "kernel.all.io";
poor_read_hits =
    (($blkio.lread - $blkio.bread) / $blkio.lread) < 0.8 && $blkio.lread > 100
	-> alarm 20 min "poor buffer cache read hit ratio (%v)";
	    // Note:	%v in alarm string is bound to the left most
	    //		expression in the predicate
