OpenSolaris storage wishlist
A number of opensolaris communities have asked their members for feedback, and the list of technologies they would like to see added in the future. The storage community received a ton of feedback when they asked the community for the list of features they would like to have added to opensolaris, and this feedback was recently posted to the genunix wiki. If there are features you are interested in that don't appear on the list, I would highly recommend adding them. There are so many cool things underway (Comstar, CIFS client and server, NPIV support, pNFS, better remote replication, etc.) in the storage community, and it's awesome to see the storage project leaders reaching out to the community to get their ideas!
$ read more →Substituting text in the HTTP request body with mod_substitute
While doing a bit of research tonight I came across a reference to mod_substitute. This nifty module allows you to substitute text in the HTTP request body, which provides an easy way to do things similar to the following: I digs me some Apache!
$ read more →Resources from my Java performance presentation
I gave a presentation last night on debugging Java performance problems. I got a couple of requests to post links to the performance analysis tools I discussed, so here you go: DTraceToolkit Garbage collection log visualization utility Garbage collection visualization utility Java hotspot DTrace provider Java heap profiling agent Monitoring garbage collection with jstat Observing object allocation with DTrace Trending Java performance I would like to thank everyone for attending, and hope to see ya'll at a future meeting!
$ read more →Figuring out which package a Solaris utility belongs to
While reading through some old notes this weekend, I came across a page I created eons ago about managing Solaris packages. If you want to find out the file modes, the user and group ownership and the package a file belongs to, you can run the pkgchk utility with the "-l" and "-p" options and the name of a file to check: Pkgchk is a nifty utility!
$ read more →Profiling Java methods with the heap profiling agent
The Java SDK comes with a number of tools and JVM options that can be used to analyze the performance of the Java runtime. One extremely useful tool is the heap profiler agent, which provides facilities to profile memory usage, CPU utilization and lock contention. To load the profiler agent to profile CPU utilization, you can add the "-agentlib:hprof=cpu=times" option to your java command line: Once loaded, the agent will use byte code injection (BCI) to instrument each method's entry and return points. This allows the agent to measure the number of times each method was called, the time spent in each method, and the call chain that led to the method being invoked…
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