//
// nested quantification
//

Servers = ":moomba :gonzo";		// change as desired

// read and write rate per disk per host
//
rd = disk.dev.read $Servers;
wr = disk.dev.write $Servers;

// one value per host, true if 20% or more of the disks are doing
// significant reading or writing
//
rd_20 = 20%_inst disk.dev.read $Servers > 40;
wr_20 = 20%_inst disk.dev.write $Servers > 40;

// single truth value: more than 20% of the disks busy reading or writing
//			on all hosts?
//
summary = all_host ( 
		20%_inst disk.dev.read $Servers > 40 || 
		20%_inst disk.dev.write $Servers > 40
	    );

// alternate form
//
summary2 = all_host (
		20%_inst (
		    disk.dev.read $Servers > 40 ||
		    disk.dev.write $Servers > 40
		)
	  );