Thanks Mac that's more or less what I did but didn't use LinkToFile, rather used Filename 

Set stream=##class(%FileCharacterStream).%New()
Set stream.Filename=FileAfUnZip
While 'stream.AtEnd {
Set ReadFFTData=stream.ReadLine()

}
 

Thanks

Thanks Dmitry, and actually changing to code to copy to filestream then read from it improved a lot, down to 1 sec 

Thank again  

Thanks Davide, but assigning this new resource to the application or  Zen page which is part of my application, would this prohibit other current users from accessing it?

Thanks

It's already running and I want to stop or pause the current running one as attached

Not sure with option to tick on, do you mean Enable option as below ?

Thanks Yaron