Swift Coz (Linux Only)

Coz profiler Swift wrapper/bindings.

This is a Swift wrapper around the Coz profiler here: https://github.com/plasma-umass/coz inspired from https://github.com/urjitbhatia/cozgo (method names, example and this README.md)

Code Usage

Coz Call	Equivalent Swift Coz Call	Description
COZ_BEGIN("name")	cozBegin("name")	Begin a latency profiling block identified by the name
COZ_END("name")	cozEnd("name")	End a latency profiling block identified by the name
COZ_PROGRESS()	cozProgress()	Specify a progress point within a block of work
COZ_PROGRESS()	cozProgressNamed("name")	Specify a named progress point within a block of work

For background on causal profiling, see

Paper: http://www.sigops.org/s/conferences/sosp/2015/current/2015-Monterey/printable/090-curtsinger.pdf

Blog: https://morsmachine.dk/causalprof

Running/Usage - Coz works only on Linux

• Install Coz: https://github.com/plasma-umass/coz
  • For OS X users, the easiest way is to run a docker image with linux for Swift (Intel: https://hub.docker.com/_/swift or Arm64: https://hub.docker.com/r/swiftarm/swift)
  • Install Coz: apt update && apt install coz-profiler
• Add Swift Coz dependency to Your Package.swift:

let package = Package(
  name: "SomePackage",
  dependencies: [
    .package(
      url: "https://github.com/funcmike/swift-coz.git", .branch("main")
    )
  ],
  targets: [
    .executableTarget(
      name: "SomeTarget",
      dependencies: [
        .product(name: "Coz", package: "swift-coz"),
      ]
    ),
  ]

• Import Swift Coz: import Coz
• Call the Coz wrappers in your application
  • See the Code Usage
• Build your swift binary with debug symbols: swift build -c debug and Check directory with binary: swift build -c debug --show-bin-path
• Run your application with Coz: coz run --- /path/to/yourSwiftBinary
• Let the application run for a while (you might want to run some load test etc, so that the profiler can pick up usage data)
• By default, Coz will create a file called profile.coz
• Use the Coz viewer to analyze the profile (run: node's http-server in viewer directory of Coz repository https://github.com/plasma-umass/coz)