Author Archives: tobias

Calculate the minimum waste when cutting planks…

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I made a web application which will calculate the most optimum layout of your pieces you would like to cut from a plank. This helps in figuring out how many planks of a certain size you would have to buy, and also gives you which pieces should be cut out on each plank.

Not sure how many times I have been sitting there, trying to figure out how many to buy, and now I simply thought that a small web-app would be nice. In fact I tried to google this, but it turns out that most people say stuff like, well add 10-15% to the total length, but that just does not work for me, that is way to inaccurate.

This page is currently in Swedish only, but until it has been translated, I bet you will understand anyway, the user interface is pretty easy to use (should not require any translation I think)…

anyway, here is the link; spill.tsoft.se

Enjoy!

-Tobias

DTrace;ing the JVM, useful tips

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I am using DTrace from time to time and it is really nice, you can do a lot with it.

This page is mostly a reminder to myself cause there are tons of pages out there if you google it, but I figured that why not share the knowledge 🙂

List all Probes available in a process

 List all probes that has to do with the JAVA JVM Hotspot

dtrace -l | grep hotspot

Figure out WHO initiated the Garbage Collection (GC)

dtrace -n ‘hotspot$target:::gc-begin { jstack(); }’ -p 25736

JVM Probes

http://docs.oracle.com/javase/6/docs/technotes/guides/vm/dtrace.html

Figure out what objects are being allocated using DTrace

http://prefetch.net/blog/index.php/2007/10/31/using-the-dtrace-hotspot-provider-to-observe-java-object-allocations/

JVM: Unable to open door

The jinfo command needs to be run by the user the JVM runs as.