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I'm drooling over this slick physics simulation of a cloth/fishnet curtain in JavaScript. You can interact with the kinematics of the canvas and tweak the source code live in your browser: http://codepen.io/stuffit/pen/KrAwx Left mouse button dragging moves the curtain; right mouse button dragging cuts through the curtain. The power and simplicity of the software engineering tech stack shown here is.... beautiful. Inspiring. (tested in Chrome and IE10; YMMV for <IE10)

There are several issues at hand here. First, killing an application instead or exiting it is very similar to using the abort button in a LabVIEW VI. It is a bit like stopping your car by running it in a concrete wall. Works very quickly and perfectly if your only concern is to stop as fast as possible but the causalities "might" be significant. LabVIEW does a lot of housekeeping when loading VIs and as a well behaved citizen of the OS it is running on attempts to release all the memory it has allocated during the course of running. Since a VI consists typically of quite a few memory blocks for the different parts of it, this amounts quickly to a lot of pointers. Running through all those tables and freeing every single memory block does cost time. In addition if you run in the IDE there is a considerable amount of framework providers that hook the application exit event and do their own release of VI resources before they even let LabVIEW itself go to start working on the actual memory block allocations. As more toolkits and extensions you have installed as longer the IDE will take to unload. Now on most modern OS systems the OS will actually do cleanup on exit of an application so strictly speaking it is not really necessary to cleanup before exit. But this cleanup is limited to resources that the OS has allocated through normal means on request of the application. It includes things like memory allocations and OS handles such as files, network sockets, and synchronization objects such as events and queues. It works fairly well and seems almost instantaneous but only because much of the work is done in the background. Windows won't maintain a list of every memory block allocated by an application but manages memory in pages that get allocated to the process. So releasing that memory is not like having to walk a list of 1000ds of pointers and deallocating them one for one, but it simply changes a few bytes in its page allocation manager and the memory page is suddenly freed per 4K or even bigger junks. Collecting all the handles that the OS has created on behalves of the application is a more involved process and takes time but can be done in a background process so the application seems to be terminated but its resources aren't yet fully claimed right away. That is for instance why a network socket usually isn't immediately available for reopening when it was closed implicitly. The problem is that relying on the OS to clean up everything is a very insecure way of going about the matter. There are differences between OS versions which resources get properly claimed after process termination and even bigger differences between different OS platforms. Most modern desktop OSes do a pretty good job in that, the RT systems do very little in that respect. On the other hand it is not common to start and stop RT control tasks frequently (except during development) so that might be not a to bad situation either. Simply going to deallocate everything properly before exiting is the most secure way of operation. If they would decide to "optimize" the application shutdown by only deallocating the resources that are known to cause problems, I'm sure there would be a handful of developers getting tied up by this to write test cases for the different OSes, and add unit tests to the daily test build runs to verify that the assumptions about what to deallocate and what not are still valid on all supported OSes and versions. It might be also a very strong reason to scrap support for any OS version immediately that is older than 2 years in order to keep the possible permutations for the unit tests manageable. And that trimming the working set has negative impact on the process termination time, is quite logical in most cases. It really only helps if there is a lot of memory blocks (not necessarily MBs) that has been allocated previously and freed later on. The trimming will release any memory pages that are not used by the application anymore to the OS and page out all the others but the most frequently accessed ones to the page file. Since the memory blocks allocated for all the VIs are still valid, trimming can not free the pages they are located in and will therefore page them out. Only when the VIs are released (unloaded) are those blocks freed but in order for the OS to free them it has to access them which triggers the paging handler to map those blocks back into memory. So trimming the memory set has potentially returned some huge memory blocks to the OS that had been used for the analysis part in the application but were then freed by LabVIEW, and will simply be reclaimed by LabVIEW when needed again. But it also paged out all the memory blocks where the VI structures are stored for the large VI hierarchy and when LabVIEW then goes and unloads the VI hierarchy it triggers the virtual memory manager many times while freeing all the memory associated with the VI hierarchy. And the virtual memory manager is a VERY slow beast in comparison to most other things on the computer, since it needs to interrupt the entire OS for the duration of its operation in order to not corrupt the memory management tables of the OS.

Here's a VI that shows how to do the same thing, but with public properties/methods. Saved in LabVIEW 2012. Get Owning Project Name.vi

Yes. It shouldn’t matter how deep in the call chain the reference is created. BTW, what is the semaphore for?