When I start any performance analysis, I begin with a blank document, with the exception of the section headings listed in the previous section and shown in Figure 1-2. Here, I perform a detailed analysis on each circle, copying and pasting, making notes, and slowly and iteratively cleaning up the document. I usually start with the Oracle analysis, as that guides me to what kind of SQL I'm looking for and what to expect from the operating system. But, honestly, sometimes I start with the operating system.

When I first perform my analysis, while the overall structure is set, the document is essentially a scratch pad. Sure, it's full of report output and technical details, but it also contains comments, ideas, and offhand remarks. These are meant for my eyes only, as they contain undeveloped, untested, and miscellaneous ideas. I will never show this raw document to management. Only when I have a chance to back off a bit and rest, and then make a second pass will I allow anyone other than the DBAs to view my work.

Once I have completed my 3-circle analysis, I repeatedly go over each circle, and then work on clearly establishing each circle's relationship with the others. Detailed circle-specific solutions will naturally result. Eventually, the overall performance situation will become apparent and can be summarized in only one or two sentences. If I cannot quickly summarize the situation, then I know my analysis is somehow flawed or incomplete.