How to get memory usage of my application and system in swift by programatically

Question

How to get memory usage of my application and system in swift by programatically?

not only system, but also my application

Answer 1

For Swift 3.0 you can use the following function.

func report_memory() {
    var taskInfo = mach_task_basic_info()
    var count = mach_msg_type_number_t(MemoryLayout<mach_task_basic_info>.size)/4
    let kerr: kern_return_t = withUnsafeMutablePointer(to: &taskInfo) {
        $0.withMemoryRebound(to: integer_t.self, capacity: 1) {
            task_info(mach_task_self_, task_flavor_t(MACH_TASK_BASIC_INFO), $0, &count)
        }
    }

    if kerr == KERN_SUCCESS {
        print("Memory used in bytes: \(taskInfo.resident_size)")
    }
    else {
        print("Error with task_info(): " +
            (String(cString: mach_error_string(kerr), encoding: String.Encoding.ascii) ?? "unknown error"))
    }
}

Answer 2

Found and tested this on XCode 12.2 and Mac OS Catalina 10.15.6 and it works like charm:

func memoryFootprint() -> Float? {
    // The `TASK_VM_INFO_COUNT` and `TASK_VM_INFO_REV1_COUNT` macros are too
    // complex for the Swift C importer, so we have to define them ourselves.
    let TASK_VM_INFO_COUNT = mach_msg_type_number_t(MemoryLayout<task_vm_info_data_t>.size / MemoryLayout<integer_t>.size)
    let TASK_VM_INFO_REV1_COUNT = mach_msg_type_number_t(MemoryLayout.offset(of: \task_vm_info_data_t.min_address)! / MemoryLayout<integer_t>.size)
    var info = task_vm_info_data_t()
    var count = TASK_VM_INFO_COUNT
    let kr = withUnsafeMutablePointer(to: &info) { infoPtr in
        infoPtr.withMemoryRebound(to: integer_t.self, capacity: Int(count)) { intPtr in
            task_info(mach_task_self_, task_flavor_t(TASK_VM_INFO), intPtr, &count)
        }
    }
    guard
        kr == KERN_SUCCESS,
        count >= TASK_VM_INFO_REV1_COUNT
    else { return nil }
    
    let usedBytes = Float(info.phys_footprint)
    return usedBytes
    
}

func formattedMemoryFootprint() -> String {
    let usedBytes: UInt64? = UInt64(self.memoryFootprint() ?? 0)
    let usedMB = Double(usedBytes ?? 0) / 1024 / 1024
    let usedMBAsString: String = "Memory Used by App: \(usedMB)MB"
    return usedMBAsString
}

Hope this helps someone too :)