Question

I have a program that processes high volumes of data, and can cache much of it for reuse with subsequent records in memory. The more I cache, the faster it works. But if I cache too much, boom, start over, and that takes a lot longer!

I haven’t been too successful trying to do anything after the exception occurs – I can’t get enough memory to do anything.

Also I’ve tried allocating a huge object, then de-allocating it right away, with inconsistent results. Maybe I’m doing something wrong?

Anyway, what I’m stuck with is just setting a hardcoded limit on the # of cached objects that, from experience, seems to be low enough. Any better Ideas? thanks.

edit after answer

The following code seems to be doing exactly what I want:

Loop 
    Dim memFailPoint As MemoryFailPoint = Nothing
    Try
        memFailPoint = New MemoryFailPoint( mysize) ''// size of MB of several objects I'm about to add to cache 
        memFailPoint.Dispose()
    Catch ex As InsufficientMemoryException
        ''// dump the oldest items here
    End Try
   ''// do work
next loop.

I need to test if it is slowing things down in this arrangement or not, but I can see the yellow line in Task Manager looking like a very healthy sawtooth pattern with a consistent top – yay!!

Answer 1

You can use MemoryFailPoint to check for available memory before allocating.