I recently talked with Mike Brunt, CF Server tuning guru for TeraTech about how he approaches slow and crashing server issues. Mike will be talking in more detail on this topic at the webinar on server tuning on Thursday 1/31/08 1pm EST. Here is what he said.

In our last blog posting I likened some time I spent in TeleRadiology to diagnosing web application problems, or more to the point, my observations as to how Radiologists work when diagnosing problems with patients. Obviously, Radiologists have medical images to use in their diagnoses, in the case of application or server problem diagnosis we do not have that sort of information to study. As a note point, SeeFusion and FusionReactor did usher in the era of great troubleshooting tools for ColdFusion-JRun. This was obviously followed by Adobe with ColdFusion 8 and the server monitoring tools; so then with these tools at our disposal is that really enough to help finally stem the flow of poorly performing applications from getting into Production?

In the same way that seeing an image with a tumor will not cure the tumor, looking at data from server monitoring will not cure performance or stability issues. Also, what if we have a pre-CF8 application in trouble, we certainly do not have CF Server Diagnostics to help us; if it is pre CFMX we have no third party tools to give us the sort of diagnoses that SeeFusion or FusionReactor provides.There is a savior for such situations which has been with us since the early days of ColdFusion; the ColdFusion logs.

Until SeeFusion was launched, the CF logs were our main source of information for diagnosing and fixing ColdFusion application issues. They are still an invaluable tool for me in all of the work that I do in finding a fixing problems and are particularly valuable to me before I go on site or commence any project. Here are what I found to be the most useful logs for my work.

CFMX-CF8 – Since the launch of CFMX 6.1 there have been two sets of logs, the “traditional” ColdFusion logs and logs relating to the J2EE status of JRun and ColdFusion we should all now and love live in one of two places, depending on the install.

Traditional ColdFusion Logs – Location
COLDFUSION STANDARD-SERVER {drive-volume}\CFusionMX7\logs\
COLDFUSION ENTERPRISE MULTI-INSTANCE {drive-volume}\JRun4\servers\{instancename}\cfusion.ear\cfusion.war\WEB-INF\cfusion\logs\

In these logs I find the application.log and the server.log with slow running request logging to the server log. This can be set in CF Admin. As a note point, the application.log for a well written/running CF Application in Production should be very small.

J2EE Logs – Location
COLDFUSION STANDARD-SERVER {drive-volume}\CFusionMX7\runtime\logs\
COLDFUSION ENTERPRISE MULTI-INSTANCE {drive-volume}\JRun4\logs\ (one set of logs for each server instance).