Section 1.2. Drill-Down Analysis

1.2. Drill-Down Analysis

To see how these tools may be used together, let us introduce the strategy of drill-down analysis (also called drill-down monitoring). This is where we begin examining the entire system and then narrow down to specific areas based on our findings. The following steps describe a drill-down analysis strategy.

1. Monitoring. Using a system to record statistics over time. This data may reveal long term patterns that may be missed when using the regular stat tools. Monitoring may involve using SunMC, SNMP or sar.

2. Identification. For narrowing the investigation to particular resources, and identifying possible bottlenecks. This may include kstat and procfs tools.

3. Analysis. For further examination of particular system areas. This may make use of TRuss, DTrace, and MDB.

Note that there is no one tool to rule them all; while DTrace has the capability for both monitoring and identifying problems, it is best suited for deeper analysis. Identification may be best served by the kstat counters, which are already available and maintained.

It is also important to note that many sites may have critical applications where it may be appropriate to use additional tools. For example, it may not be suitably effective to monitor a critical Web server using ping(1M) alone, instead a tool that simulates client activity while measuring response time and expected content may prove more effective.