Perfect SysInfo

This project provides a Swift library to monitor system performance.

This package builds with Swift Package Manager and is part of the Perfect project but can also be used as an independent module.

Ensure you have installed and activated the latest Swift 3.1 tool chain.

Quick Start

Add Perfect SysInfo library to your Package.swift:

.Package(url: "https://github.com/PerfectlySoft/Perfect-SysInfo.git", majorVersion: 1)

Add library header to your source code:

import PerfectSysInfo

Now SysInfo class is available to call.

CPU Usage

Call static variable SysInfo.CPU will return a dictionary [String: [String: Int]] of all CPU usage, for example:

print(SysInfo.CPU)

//here is a typical return of single CPU (from Linux): 

[
  "cpu0":
    ["nice": 1201, "system": 3598, "user": 8432, "idle": 8657606],
  "cpu":
    ["nice": 1201, "system": 3598, "user": 8432, "idle": 8657606]
]

// and the following is another example with 8 cores (from Mac):
[
  "cpu3":
    ["user": 18095, "idle": 9708265, "nice": 0, "system": 16177],
  "cpu5":
    ["user": 18032, "idle": 9708329, "nice": 0, "system": 16079],
  "cpu7":
    ["user": 18186, "idle": 9707892, "nice": 0, "system": 16285],
  "cpu":
    ["user": 344301, "idle": 9201762, "nice": 0, "system": 196763],
  "cpu0":
    ["user": 730263, "idle": 8387000, "nice": 0, "system": 626684],
  "cpu2":
    ["user": 648287, "idle": 8799969, "nice": 0, "system": 294749],
  "cpu1":
    ["user": 17708, "idle": 9708996, "nice": 0, "system": 15950],
  "cpu4":
    ["user": 647701, "idle": 8800643, "nice": 0, "system": 294544],
  "cpu6": ["user": 656136, "idle": 8793002, "nice": 0, "system": 293640]
]

The record is a structure of N+1 entries, where N is the number of CPU and 1 is the summary, so the each record will be tagged with "cpu0" ... "cpuN-1" and the tag "cpu" represents the average of overall. Each entries will contain idle, user, system and nice to represent the cpu usage time. In a common sense, idle shall be as large as possible to indicate the CPU is not busy.

Memory Usage

Call static property SysInfo.Memory will return a dictionary [String: Int] with memory metrics in ** MB **:

print(SysInfo.Memory)

** Note ** Since system information is subject to operating system type, so please use directive #if os(Linux) #else #endif determine OS type before reading system metrics; The definition of each counter is out of the scope of this document, please see OS manual for detail.

Typical Linux memory looks like this ( 1G total memory with about 599MB available):

[
  "Inactive": 283, "MemTotal": 992, "CmaFree": 0,
  "VmallocTotal": 33554431, "CmaTotal": 0, "Mapped": 74,
  "SUnreclaim": 14, "Writeback": 0, "Active(anon)": 98,
  "Shmem": 26, "PageTables": 7, "VmallocUsed": 0,
  "MemFree": 98, "Inactive(file)": 179, "SwapCached": 0,
  "HugePages_Total": 0, "Inactive(anon)": 104, "HugePages_Rsvd": 0,
  "Buffers": 21, "SReclaimable": 39, "Cached": 613,
  "Mlocked": 3, "SwapTotal": 1021, "NFS_Unstable": 0,
  "CommitLimit": 1518, "Hugepagesize": 2, "SwapFree": 1016,
  "WritebackTmp": 0, "Committed_AS": 1410, "AnonHugePages": 130,
  "DirectMap2M": 966, "Unevictable": 3, "HugePages_Surp": 0,
  "Dirty": 3, "HugePages_Free": 0, "MemAvailable": 599,
  "Active(file)": 426, "Slab": 54, "Active": 525,
  "KernelStack": 2, "VmallocChunk": 0, "AnonPages": 177,
  "Bounce": 0, "HardwareCorrupted": 0, "DirectMap4k": 57
]

And here is a typical mac OS X memory summary, which indicates that there is about 4.5GB free memory:

[
  "hits": 0, "faults": 3154324, "cow": 31476,
  "wired": 3576, "reactivations": 366, "zero_filled": 2296248,
  "pageins": 13983, "lookups": 1021, "pageouts": 0,
  "active": 6967, "free": 4455, "inactive": 1008
]

Network Traffic

Call static property SysInfo.Net will return total traffic summary from all interfaces as a dictionary [String: [String: Int]] where the key represents the network interface name, and the value is a detailed dictionary with two key-value pairs - i stands for receiving and o for transmitting, both in KB:

if let net = SysInfo.Net {
  print(net)
}

If success, it will print something like these mac / linux outputs:

// typical mac os x network summary, where the only physical network
// adapter "en0" has 1MB incoming data totally.

[
    "p2p0": ["o": 0, "i": 0], 
    "stf0": ["o": 0, "i": 0], 
    "vboxnet0": ["o": 0, "i": 1], 
    "gif0": ["o": 0, "i": 0], 
    "lo0": ["o": 0, "i": 887], 
    "bridge0": ["o": 0, "i": 0], 
    "utun0": ["o": 0, "i": 0], 
    "awdl0": ["o": 0, "i": 318], 
    "en1": ["o": 0, "i": 0], 
    "en0": ["o": 0, "i": 1063], 
    "en2": ["o": 0, "i": 0]
]

// typical linux network summary, where the only physical network
// adapter "enp0s3" has received 0.6MB data and sent out 506KB in the same time.

[
    "virbr0": ["o": 0, "i": 0], 
    "enp0s8": ["o": 506, "i": 614], 
    "virbr0-nic": ["o": 0, "i": 0], 
    "lo": ["o": 1804, "i": 1804], 
    "enp0s3": ["o": 158, "i": 7594]
]

Disk IO

Call static method SysInfo.Disk may inspect disk i/o activity statistics in real time. It will return a [String:[String: UInt64]] dictionary with metrics as sample below. For more information of these counters, please refer to the operating system manual.

Linux Release Notes

print(SysInfo.Disk)

// here is a sample output from Linux:
[
  "sda":
    [
      "io_ms": 7516, "reads_merged": 17, "reads_completed": 14993,
      "writing_ms": 9772, "io_in_progress": 0, "writes_completed": 4921,
      "sectors_read": 1292762, "reading_ms": 11952, "writes_merged": 5738,
      "sectors_written": 969480, "weighte_io_ms": 21636
    ],
  "sda2":
    [
      "io_ms": 0, "reads_merged": 0, "reads_completed": 4,
      "writing_ms": 0, "io_in_progress": 0, "writes_completed": 0,
      "sectors_read": 8, "reading_ms": 0, "writes_merged": 0,
      "sectors_written": 0, "weighte_io_ms": 0
    ],
  "sda1":
    [
      "io_ms": 7252, "reads_merged": 7, "reads_completed": 14817,
      "writing_ms": 9520, "io_in_progress": 0, "writes_completed": 3971,
      "sectors_read": 1281954, "reading_ms": 11908, "writes_merged": 5426,
      "sectors_written": 966696, "weighte_io_ms": 21340
    ]
]

Mac OS X Release Notes

Please note that if using SysInfo.Disk in a loop, then an autoreleasepool{ } is strongly recommend to avoid unnecessary memory caching on such objects:

autoreleasepool(invoking: {
  let io = SysInfo.Disk
  print(io)
})

// here is the sample output from macOS:
[
  "disk0":
    [
      "operations_read": 501077, "latency_time_read": 0,
      "bytes_written": 21265645056, "bytes_read": 25022815232,
      "operations_written": 360598, "latency_time_written": 0
    ]
]