RT 50% memory step increase

[sgregor249]

Hi all,

I am using the rtgetmemorysummary.vi located at http://zone.ni.com/devzone/cda/epd/p/id/4952 to monitor the memory usage of a real time application. I use the total and available outputs to calculate the percent usage, and log this to file. I have seen a step change from roughly 11 to 60 percent usage on two different RT systems. After the increase occurs, the system maintains 60% memory consumption. This rare occurrence has happened twice within the course of maybe two months.

 National Instruments has verified that this VI is the same as the RT memory monitoring VI in the 8.6 RT package. I am wondering if anyone has seen a sudden step change in memory usage, similar to what I have described. I am not sure if calling this VI is causing the memory to spike or if this is a false report, or if the code is causing a whopping 256Mb allocation. So, does anybody have any similar experiences and possible solutions?

LAVA Crosspost: http://forums.lavag.org/50-RT-Memory-Step-Increase-t14127.html

[mallyaprs]

Hi,

Can you give more info on this. Which target are you using ?, When is this escalation happening ?, is this happening whien you run get mem usage.vi ( when nothing else is deployed) or is it happening  cos of your code. You can use RT system manger to log an alert when the memory usage reaches a point and then try to debug the issue.

[sgregor249]

I have two PXI systems with PXI 8106 controllers. The escalation seems to happen randomly. I have only seen it occur twice within the course of two months, so i can not find an obvious trigger. The spike occurs when my entire software (get mem usage.vi and a lot of other VIs) is running as a build on the RT systems, so i am not sure if it is my code or the VI to monitor the memory usage. I need to monitor the memory usage programatically, in order to protect a unit under test. I know about the real time system manager, if this can reveal which VI  is instantaneously allocaing 256Mb of memory then this will be a HUGE help. I will look into this more.

Thank you!