"Place the Request Deallocation function in the subVI you want to deallocate memory for. When you set the flag Boolean input to TRUE, LabVIEW reduces memory usage by deallocating the data space for the subVI."
Please give us an example for it, it's very interested for me
Is there anything in the help for the request deallocation function that is not clear to you? What kind of problems are you experiencing?
Most often, the "request deallocation" function is not the solution. It can actually hurt performance.
(You added to a 6 year old thread and many things have probably changed since.)
Please help me Dear Knight of NI !
I'm actively using Database toolkit with LV2009 and my task is writing into PostgreSQL every 20...40 second some simple data into only table (into 10...15 columns).
So after download into memory my exe file I see that 65 MB is occupy my exe, and on the next day I see that my exe has become 81 MB.
My application is intended for 24/7
If you're opening and closing the database connection every time that's a common result. The old connections are resident in memory or fragmented so they're hard to reuse or something. Open at program start, close at end. 🙂
Is there any other variant?
Simply I open and close my refs there where I need in my program and many times.
Nevertheless memory leak is growing... I do my application for LV program rules! Why memory is leaking?
Is anybody here that did big 24/7 applications on the LV ???
I've never seen
That big? I've working with a 700 vi program right now, my previous project was 4000 vi's.
The amount of memory needed is depending on what's happening and also the runtime. When running out program was some 2-300 Mb.
Look up Action Engines. Use one to store the database ref. Create an Open DB which opens and stores the ref. Get the ref and use it in your database query instead of opening a new one. When closing the program, use a Close ref in the AE to close it.
The memory is growing because you allocate a new database connection each query.
4000 vi's.... So many ?! And 300 MB running out... Ohh
I'm very glad to see the LabVIEW professional! In my project only 180 vi's but one is about 800 KB
In the matter of fact you are quite right - "The memory is growing because you allocate a new database connection each query"
nevertheless then rules of LabVIEW are not working