Performance Management IACT 418/918 Autumn 2005 Gene Awyzio SITACS University of Wollongong

2 Overview Performance Management is the process of ensuring that –Network devices are NOT overloaded –Links are NOT saturated This is achieved by –Monitoring devices and links to determine utilisation and error rates –Helping network to provide consistent service by Ensuring capacity of devices and links are not overtaxed and thus impacting on performance Performance management involves the following steps –Data collection –Data analysis –Setting thresholds –Using simulation

3 Benefits of the Performance Management Process Reduces problems of –Network overcrowding –Network inaccessibility Collected data can be used to –Isolate components that are heavily utilised –Determine utilisation trends Peak loads High load periods Scheduling of data transfers –Isolate performance problems

4 Accomplishing Performance Management Performance management involves the following steps –Data collection –Data analysis –Setting thresholds –Using simulation

5 Data Collection Data required is the current utilisation of network devices and links File server –Packet forwarding rate –Processor load –% of dropped frames –Disk access rate

6 Data Collection Bridge or Router –Packet forwarding rate –% of dropped frames –Queue lengths Links –(bits sent + bits received)/bandwidth –MAX (bits sent, bits received)/bandwidth – Full duplex

7 Data Collection Level of service –Total response time –Rejection rate –Availability

8 Data Analysis Real time or historical –RT useful for troubleshooting Device information: memory usage, processor utilisation, disk access rate etc Link Information: utilisation, error rates, error % etc –Historical useful for trend analysis Capacity planning Network redesign Error trends Bar or line

9 Setting Thresholds Utilisation thresholds may be set on –Devices Processor utilisation Alarm duration –Links Error rate Average utilisation Overall throughput/goodput Reports can be generated when thresholds are reached

10 Setting Thresholds Determining thresholds can be a bit of a hit-and-miss activity Thresholds will enable the network manager to locate and fix a problem BEFORE it affects the network

11 Using Simulation Simulation can be used to –Determine how to reconfigure network –Assess the impact of a new application –Assess impact of application configuration

12 Performance Management on a Network Management System Simple –Monitor real time performance of devices and links –Produce graphs for review More complex –Capture data to a database –Provide means for setting thresholds –Set alarms based on thresholds Advanced –Historical analysis –Network simulation

13 Reporting Performance Information Can be achieved in may forms –Text based –Graphical Charts Link colour or thickness Flashing –Iconic