System and method for performing capacity planning for enterprise applications

Abstract

A system and method for capacity planning for enterprise networks, such as identifying bottlenecks and removing or replacing the bottleneck device are provided. The device utilization for one or more network devices are measured or read from measured data. A relative load is calculated from the device utilization data and device utilization is compared to a device threshold to determine the bottleneck device. A method is also provided for determining network utilizations, network populations and a relative response times based on only limited measurable device usage data.

1 . A method for performing a capacity upgrade on a given network comprising a set of network devices to an upgraded network comprising:
 normalizing stored network device speeds associated with network devices in the given network to a constant value;   replacing one or more network devices in the given network with one or more new network devices;   calculating relative speeds for the one or more new network devices; and,   predicting network device utilizations for network devices in the upgraded network for one or more relative load values.   
     
     
         2 . The method of  claim 1  in which replacing one or more network devices in the given network with one or more new network devices is performed after calculating relative speeds for the new network devices. 
     
     
         3 . The method of  claim 1  in which replacing one or more network devices in the given network with one or more new network devices is performed before normalizing stored network device speeds associated with network devices in the given network to a constant value. 
     
     
         4 . The method of  claim 1  wherein predicting network device utilizations for network devices in the upgraded network for one or more relative load values comprises calculating device utilizations at a base load. 
     
     
         5 . A method for determining network response times within the process of performing network capacity planning for a given network, the method comprising:
 obtaining network usage data; and   calculating relative network response times at one or more relative load values based on the network usage data.   
     
     
         6 . The method of  claim 5  wherein obtaining network usage data includes measuring network usage data. 
     
     
         7 . The method of  claim 5  wherein obtaining network usage data includes measurement of an absolute network response time. 
     
     
         8 . The method of  claim 5  wherein obtaining network usage data includes calculating relative load network population from prior measured usage data. 
     
     
         9 . The method of  claim 5  wherein calculating relative network response times at one or more relative load values further comprises:
 defining a base load that is associated with the given network; 
 normalizing the relative network response time at the base load to a constant value; and, calculating a the relative response time R(x) for the relative load values according to the formula: 
 R(x)=(N.sub.0(x)/N.sub.0(1))/x wherein x is a relative load value; N.sub.0(x) is the relative load network population at relative load value x and N.sub.0(1) is the base load network population at the base load x=1. 
 
     
     
         10 . The method of  claim 5  further comprising calculating absolute network response times corresponding to relative network response times at one or more relative load values wherein calculating said absolute response time includes multiplying a relative response time at a relative load value by the absolute response time at the base load. 
     
     
         11 . The method of  claim 9  wherein normalizing the relative response time at the base load, the constant value is set equal to one. 
     
     
         12 . The method of  claim 5  wherein calculating network response times at one or more relative load values comprises:
 fitting response times to a known functional form, the relative load value being the dependent variable in said functional form; 
 storing the constants generated by the functional fit in a computer memory; and, 
 utilizing the functional fit in the capacity planning process to predict network response times for the relative load values. 
 
     
     
         13 . The method of  claim 12  wherein the response time functional fit is a function of the form
     R ( x )= a   0   +a   1   x+a   2 ( N   0 ( x )/ N   0 (1))/ x    
 wherein a 0 , a 1 , and a 2  are constants, x is the relative load value, N 0 (x) is the relative load network population at relative load value x, and N 0 (1) is the relative load network population at the base load x=1.