How to run 'echo 1 > /proc/sys/vm/drop_caches'??

[Seyong]

Hi, all

This is Seong in Korea

I'm using cRIO-9033, CVS-1458RT.

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For some reasons, I must delete system caches on system using not PuTTY but LabVIEW 2014.

I received message 'Permission denied'  when I use 'system exec.vi'. with command 'echo 1 > /proc/sys/vm/drop_caches'

But It has no problem with PuTTY.

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I already 'lvuser' insert to administrator group.

Command 'gropus' get 'administrator tty plugdev niwscerts everyone'  on LabVIEW.

Please refer to attached .png file.

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Regards,

[BradM]

Hi there, Seong.

Why do you need to drop the page caches? Are you writing a lot to disk?

Also, since this is just the disk page cache, it will be flushed when system memory runs low.

[Seyong]

Hi, BradM

In fact, I'm using a camera and VI which save file to external disk(U drive) using 'IMAQ Write File 2.vi'.

The save loop rate is about 50Hz or more and JPG file size is about 30kB.

Every file has diffent name(day+time.jpg)

My main problem is system crash cause by 'Free physical Memory decrease to zero'.

I found that cached memory increase during VI run.(I test it under Windows 7 and NI Linux.)

I run 'echo 1 > /proc/sys/vm/drop_caches' by Putty.

I think it's effective.

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So, I want to insert drop command into my main VI.

If you have another effective method, Please tell me.

In fact, I am not good at Linux.

Regards,

Seyong