Archive for 'Solaris DTrace'

Cool video on the DTrace port to Linux

This is a solid video: I can’t wait until DTrace is readily available in Linux!!

Using Solaris source code + DTrace

Brian Leonard wrote an excellent blog post about how to use DTrace, how to show details about specific probes, and then using the source code in conjunction with his findings to understand exactly what was happening within that probe. ┬áif you’re starting to deep dive into DTrace, this is an excellent article for learning these […]

Instrumenting Java code with JSDT probes

A few months back, I got wind from the world famous Jarod Jenson that Keith McGuigan was working on adding JSDT probes to Java. JSDT probes struck me as an extremely useful feature for realtime problem analysis, so I decided to instrument some sample code to see how they worked. After a couple of e-mail […]

Using the DTrace hotspot provider to observe java object allocations

In my previous post, I discussed how jmap can be used to view the contents of the Java heap. Jmap is a wonderful utility for viewing heap utilization at a specific point in time, but it’s not the best utiltiy for answer questions like “which call stack is allocating objects of type foo?”, or “how […]

Enabling the DTrace hotspot provider after the JVM starts

While debugging a JVM performance issue a while back, I encountered the following error when I enabled the DTrace hotspot provider: $ jinfo -flag +ExtendedDTraceProbes `pgrep java` 590: Unable to open door: target process not responding or HotSpot VM not loaded After a bit of debugging, I figured out that the jinfo command needs to […]

Measuring system call time with procsystime

When debugging application performance problems related to high system time, I typically start my analysis by watching the system calls the application is issuing, and measuring how much time is spent in each system call. Gathering this information is simple with DTrace syscall provider, and the DTraceToolkit comes with the procsystime script to allow admins […]

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