ReadViewSDK/Sources/RDReaderView/EPUBUI/ReaderController/RDEPUBMemoryProbe.swift
shenlei e4e629a06c 长章节内存优化 P0:每页子串改按需构造并新增内存打点
- RDEPUBTextPage.content 由存储属性改为基于 chapterContent+contentRange
  的计算属性,三处构造点不再生成每页子串,章节缓存窗口内每章少一份
  整章文本常驻副本
- 新增 RDEPUBMemoryProbe(--demo-memory-probe 开启),在章节插入、
  每 20 次翻页、设置失效、转屏完成时输出 phys_footprint
- shouldAvoidReaderPageCaching 补注释,锁定放开前置条件为 P1-1
- 新增实施清单文档 LONG_CHAPTER_MEMORY_OPTIMIZATION_PLAN.md 并勾选 P0

验证:Demo 编译通过;UI 回归 9/9 通过(PageNavigation/
ReaderOpenClose/LargeBookOnDemand)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-08 15:34:45 +09:00

44 lines
1.7 KiB
Swift

import Foundation
/// Memory footprint probe for the long-chapter optimization work
/// (Doc/LONG_CHAPTER_MEMORY_OPTIMIZATION_PLAN.md, P0-2). Enabled with the
/// `--demo-memory-probe` launch argument; logs phys_footprint at chapter
/// load, every 20 page turns, settings invalidation, and rotation.
enum RDEPUBMemoryProbe {
static let isEnabled = ProcessInfo.processInfo.arguments.contains("--demo-memory-probe")
private static let pageTurnLogStride = 20
/// Main-thread only (page turns are delivered on main).
private static var pageTurnCount = 0
static func logPageTurn() {
guard isEnabled else { return }
pageTurnCount += 1
guard pageTurnCount % pageTurnLogStride == 0 else { return }
log("pageTurn count=\(pageTurnCount)")
}
static func log(_ event: String) {
guard isEnabled else { return }
let megabytes = Double(currentFootprint()) / 1_048_576
print(String(format: "[EPUB][MemoryProbe] %@ footprint=%.1fMB", event, megabytes))
}
/// phys_footprint matches the value Xcode's memory gauge and Jetsam use.
private static func currentFootprint() -> UInt64 {
var info = task_vm_info_data_t()
var count = mach_msg_type_number_t(
MemoryLayout<task_vm_info_data_t>.size / MemoryLayout<integer_t>.size
)
let result = withUnsafeMutablePointer(to: &info) { pointer in
pointer.withMemoryRebound(to: integer_t.self, capacity: Int(count)) {
task_info(mach_task_self_, task_flavor_t(TASK_VM_INFO), $0, &count)
}
}
guard result == KERN_SUCCESS else { return 0 }
return info.phys_footprint
}
}