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Swift Dev Journal

Finding Your App’s Largest Memory Allocations

Published 3 months ago • 1 min read

When you profile your app with the Allocations instrument, you may want to find the largest memory allocations your app makes. Take the following steps to find the largest memory allocations:

  1. Press Cmd-3 to open the allocations list.
  2. Click the Size column heading to sort the allocations by size.
  3. Choose All Heap Allocations from the Allocation Type menu in the bottom bar to hide virtual memory allocations. Your code doesn’t directly make virtual memory allocations.

The Allocation Type menu is the rightmost menu in the following image:

The extended detail view shows the call stack. Clicking the button at the top right of the call stack list hides system libraries to help find your code in the call stack.

Double-click a function from the call stack to see the lines of code that allocated memory. Make sure you double-click a function you wrote or else you'll see assembly language functions instead of source code.

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