[swift-users] Object size on heap

[Jens Alfke]

> On Mar 22, 2016, at 11:04 PM, Howard Lovatt via swift-users <swift-users at swift.org> wrote:
> 
> I am writing custom collection classes and trying to assess which one is better, both in terms of performance and memory usage. Won't be used in 'real' code, just to guide development.

You might consider using heap profiling tools too, like (on Mac OS) the Instruments app or the `heap` command-line tool. If you use these while running a benchmark app using your API, it can show you how much total heap space gets used.

Actual heap usage can differ from the raw “sizeof” a data type, since allocators will often round up block sizes or return a somewhat larger block than necessary. Heap fragmentation can also increase memory usage beyond what you’d expect, and different allocation patterns can affect fragmentation.

—Jens
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.swift.org/pipermail/swift-users/attachments/20160323/9527cbeb/attachment.html>