| This graph shows average waiting time/latency for different categories of disk operations.   The times that include the queue times indicate how busy your system is.  If the waiting time hits 1 second then your I/O system is 100% busy. | 
		    
		  
		    
		    
		    
		    
			  | Field | 
			  Internal name |                          
			  Type | 
			  Warn | 
			  Crit | 
			  Info | 
		    
		  
		    
		      | Device IO time | 
		      svctm | 
		      gauge | 
		        | 
		        | 
		      Average time an I/O takes on the block device not including any queue times, just the round trip time for the disk request. | 
		    
		    
		  
		    
		      | IO Wait time | 
		      avgwait | 
		      gauge | 
		        | 
		        | 
		      Average wait time for an I/O from request start to finish (includes queue times et al) | 
		    
		    
		  
		    
		      | Read IO Wait time | 
		      avgrdwait | 
		      gauge | 
		      0:3  | 
		        | 
		      Average wait time for a read I/O from request start to finish (includes queue times et al) | 
		    
		    
		  
		    
		      | Write IO Wait time | 
		      avgwrwait | 
		      gauge | 
		      0:3  | 
		        | 
		      Average wait time for a write I/O from request start to finish (includes queue times et al) |