Re: [swift-users] Object size on heap

Thanks, you are correct. Very helpful. -- Howard. On 24 March 2016 at 11:20, Kate Stone wrote: > You’re almost certainly seeing side effects of not keeping the instance of > TestClass alive long enough for the unsafe pointer to still refer to an > allocated malloc block. A quick REPL session

Re: [swift-users] Object size on heap

You’re almost certainly seeing side effects of not keeping the instance of TestClass alive long enough for the unsafe pointer to still refer to an allocated malloc block. A quick REPL session illustrates this fact: 1> class TestClass { 2. let a = 0 3. let b: Int? = nil 4. }

Re: [swift-users] Object size on heap

@Kate, I don't seem to be able to get `malloc_...` to work. EG: class TestClass { let a = 0 let b: Int? = nil } @_silgen_name("swift_class_getInstanceExtents") func swift_class_getInstanceExtents(theClass: AnyClass) -> (negative: UInt, positive: UInt) print("swift_class_getInstanceExtents

Re: [swift-users] Object size on heap

I definitely concur that tools like Instruments are the best way to understand the impact of decisions on memory across the board. For fine-grained inquiries about memory use you can also rely on malloc family functions to make inquiries: let required_size = malloc_size(unsafeAddressOf(object_r

Re: [swift-users] Object size on heap

Thanks, I will give that a try -- Howard. On 24 March 2016 at 03:17, Jens Alfke wrote: > > On Mar 22, 2016, at 11:04 PM, Howard Lovatt via swift-users < > swift-users@swift.org> wrote: > > I am writing custom collection classes and trying to assess which one is > better, both in terms of perf

Re: [swift-users] Object size on heap

> On Mar 22, 2016, at 11:04 PM, Howard Lovatt via swift-users > 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 hea

Re: [swift-users] Object size on heap

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. -- Howard. On 23 March 2016 at 03:52, Jordan Rose wrote: > > On Mar 22, 2016, at 8:47, Joe Groff via swift-u

Re: [swift-users] Object size on heap

Many thanks -- Howard. On 23 March 2016 at 02:47, Joe Groff wrote: > > On Mar 21, 2016, at 9:31 PM, Howard Lovatt > wrote: > > How do you call swift_class_getInstanceExtents, it doesn't show in Xcode? > > > It's not provided as API by default. You can do this as an unsupported > hack: > > @_

Re: [swift-users] Object size on heap

> On Mar 22, 2016, at 8:47, Joe Groff via swift-users > wrote: > > >> On Mar 21, 2016, at 9:31 PM, Howard Lovatt > > wrote: >> >> How do you call swift_class_getInstanceExtents, it doesn't show in Xcode? > > It's not provided as API by default. You can do this

Re: [swift-users] Object size on heap

> On Mar 21, 2016, at 9:31 PM, Howard Lovatt wrote: > > How do you call swift_class_getInstanceExtents, it doesn't show in Xcode? It's not provided as API by default. You can do this as an unsupported hack: @_silgen_name("swift_class_getInstanceExtents") func swift_class_getInstanceExtents(the

Re: [swift-users] Object size on heap

How do you call swift_class_getInstanceExtents, it doesn't show in Xcode? -- Howard. On 22 March 2016 at 06:07, Joe Groff wrote: > > > On Mar 19, 2016, at 1:53 PM, Howard Lovatt via swift-users < > swift-users@swift.org> wrote: > > > > Hi, > > > > Is there a way to find out how big an object

Re: [swift-users] Object size on heap

> On Mar 19, 2016, at 1:53 PM, Howard Lovatt via swift-users > wrote: > > Hi, > > Is there a way to find out how big an object is on the heap? No public API yet. For entertainment purposes, you could use the runtime's swift_class_getInstanceExtents function, passing in the class object for t

Re: [swift-users] Object size on heap

>> Is there a way to find out how big an object is on the heap? > > Yes, the sizeof() function. I think he's asking for the size of the object itself. For a reference type, `sizeof()` gives you the size of the reference. -- Brent Royal-Gordon Architechies _

Re: [swift-users] Object size on heap

> On Mar 19, 2016, at 4:53 PM, Howard Lovatt via swift-users > wrote: > > Is there a way to find out how big an object is on the heap? Yes, the sizeof() function. —Jens___ swift-users mailing list swift-users@