mirror of
https://github.com/apple/swift-nio.git
synced 2026-05-20 20:30:36 +00:00
George Barnett
e84b2ce05a
Motivation: Our alloc regression workflows are somewhat disparate: on macOS we have dtrace and a script to diff two ouputs. On Linux we have heaptrack and bpftrace but no way to analyze their outputs. Diffing output from these tools can be quite tedious if the stacks vary even a little (because the compiler decided to not inline a function, for example). Most of the tedium in this workflow is from pairing up equivalent stacks across the two inputs. We can make this easier to do by ranking suggestions based on how similar they are and letting the user decide whether to accept the match or not. Modifications: - Add a subpackage with some internals for parsing heaptrack, aggregating stacks, and measuring the similarity between them - The CLI took is currently a no-op, it'll be added in subsequent PRs Result: Easier to diagnose alloc regressions
75 lines
2.1 KiB
Swift
75 lines
2.1 KiB
Swift
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This source file is part of the SwiftNIO open source project
|
|
//
|
|
// Copyright (c) 2025 Apple Inc. and the SwiftNIO project authors
|
|
// Licensed under Apache License v2.0
|
|
//
|
|
// See LICENSE.txt for license information
|
|
// See CONTRIBUTORS.txt for the list of SwiftNIO project authors
|
|
//
|
|
// SPDX-License-Identifier: Apache-2.0
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
public protocol StackParser {
|
|
static func parse(lines: some Sequence<String>) throws -> [WeightedStack]
|
|
}
|
|
|
|
public protocol StackProtocol {
|
|
var lines: [String] { get }
|
|
}
|
|
|
|
extension StackProtocol {
|
|
/// Returns a stack with at most `maxLength` lines from the start of the current stack.
|
|
public func prefix(_ maxLength: Int) -> PartialStack {
|
|
PartialStack(self.lines.prefix(max(0, maxLength)))
|
|
}
|
|
|
|
/// Returns a stack with at most `maxLength` lines from the end of the current stack.
|
|
public func suffix(_ maxLength: Int) -> PartialStack {
|
|
PartialStack(self.lines.suffix(max(0, maxLength)))
|
|
}
|
|
}
|
|
|
|
/// The lines of a full stack trace.
|
|
public struct Stack: Hashable, StackProtocol {
|
|
public var lines: [String]
|
|
|
|
public init(_ lines: [String]) {
|
|
self.lines = lines
|
|
}
|
|
|
|
public init(_ weighted: WeightedStack) {
|
|
self = weighted.stack
|
|
}
|
|
}
|
|
|
|
/// The lines of a possibly incomplete stack trace.
|
|
public struct PartialStack: Hashable, StackProtocol {
|
|
public var lines: [String]
|
|
|
|
public init(_ lines: some Sequence<String>) {
|
|
self.lines = Array(lines)
|
|
}
|
|
}
|
|
|
|
/// A stack with an associated number of allocations
|
|
public struct WeightedStack: Hashable, StackProtocol {
|
|
public var stack: Stack
|
|
public var allocations: Int
|
|
|
|
public var lines: [String] {
|
|
self.stack.lines
|
|
}
|
|
|
|
public init(lines: [String], allocations: Int) {
|
|
self.init(stack: Stack(lines), allocations: allocations)
|
|
}
|
|
|
|
public init(stack: Stack, allocations: Int) {
|
|
self.stack = stack
|
|
self.allocations = allocations
|
|
}
|
|
}
|