vmstat of iPadOS

vmstat.swift

import Darwin

func getVMStatistics64() -> vm_statistics64? {
    let hostPort = mach_host_self()
    var hostSize = mach_msg_type_number_t(MemoryLayout<vm_statistics64_data_t>.size / MemoryLayout<integer_t>.size)
    var vmstat = vm_statistics64()
    let result = withUnsafeMutablePointer(to: &vmstat) {
        $0.withMemoryRebound(to: integer_t.self, capacity: Int(hostSize)) {
            host_statistics64(
                hostPort,
                HOST_VM_INFO64,
                $0,
                &hostSize
            ) == KERN_SUCCESS
        }
    }
    
    return result ? vmstat : nil
}

func getPageSize() -> UInt64 {
    var pageSize: vm_size_t = 0
    host_page_size(mach_host_self(), &pageSize)
    return UInt64(pageSize)
}

let vmstat = getVMStatistics64()!
let pageSize = getPageSize()
let pageIns = Double(vmstat.pageins * pageSize) / Double(1 << 30)
let pageOuts = Double(vmstat.pageouts * pageSize) / Double(1 << 30)
let swapIns = Double(vmstat.swapins * pageSize) / Double(1 << 30)
let swapOuts = Double(vmstat.swapouts * pageSize) / Double(1 << 30)
let faults = Double(vmstat.faults * pageSize) / Double(1 << 40)
 
print("page ins: \(pageIns) GiB")
print("page outs: \(pageOuts) GiB")
print("swap ins: \(swapIns) GiB")
print("swap outs: \(swapOuts) GiB")
print("faults: \(faults) TiB")