A regular Refresh walked every configured root sequentially, so a full 25 TB drive delayed the roots behind it, and the dialog sat on "Checking for changes..." at 0 % for the whole walk with no way to tell it was working. On a cold external drive the walk itself dominates the cost, so the fix is to overlap the drives and to show what the walk is doing. Backend (py/services/model_scanner.py): * Extract the per-root walk into the synchronous _walk_root_for_reconcile() worker and merge its results on the event loop afterwards, in configured root order: which business path wins a file reachable through several roots must not depend on the order the workers happened to finish in. * Group roots by device (_root_device_key: drive letter on Windows, st_dev on POSIX) and run one worker per device. Roots sharing a device stay sequential, so directory claims and the overlap dedup (#871, #1041) keep their configured-order semantics; different devices run in parallel. * Track walk progress per root (_ReconcileWalkTracker), weighted by each root's cached entry count because the real file count is only known once the walk ends. The bar splits into walk (0-50 %) and new-file (50-99 %) phases so it never jumps backwards, and the walk broadcasts files seen, active roots and the ETA counters. * Replace the Windows case-insensitive fallback -- a scan of every cached path per miss, i.e. O(files x cached) -- with a lazily built lower-cased index (_CachedPathLookups, also now guarding the realpath alias index for worker threads), and lift the os.name == "nt" gate into the module-level _CASE_INSENSITIVE_PATHS so the branch is testable off Windows. * Excluded-model membership is a set lookup instead of a list scan. Frontend: * render the walk phase as "Checking for changes... <roots> (N files)" with the ETA, and reset the ETA tracker when the stage changes: the per-file rate of counting files says nothing about processing them. * add common.scanProgress.walkFiles; the other locales keep the sanctioned [TODO: Translate] placeholder until the translation pass. Verified: no-change reconcile over 10k files/500 dirs 101 ms and 10k/5000 dirs 230 ms (was 93/229 ms, within noise); a two-device sandbox walk runs both roots concurrently, names them in the progress messages and finishes with added=15, removed=0; 3665 passed, 7 skipped; frontend 1456 passed, vue widgets 96 passed.
4.2 KiB
Reconcile 的 Windows 大小写回退分支
状态: 已改为 O(1) 索引(2026-10-06),不再需要 Windows 机器验证 | 创建日期: 2026-09-11 相关文件:
py/services/model_scanner.py(_walk_root_for_reconcile/_CachedPathLookups) 相关历史: #871 (76ee59cd, 路径重叠去重)、#1108 (按文件夹扫描的需求)
背景
Refresh 按钮走的是 _reconcile_cache()(快速增量对账)。2026-09-11 做了一轮性能优化,把两处"预防性"的
realpath 全量遍历改成按需触发。清理时留下的唯一可疑点,是 Windows 专属的大小写不敏感回退分支:它排在
精确匹配和 realpath 别名匹配之后,只有未命中的文件才会走到,但一旦走到就是 O(文件数 × 缓存条目数)。
现状(已改造)
分支语义保持不变,查找改为 O(1):
if _CASE_INSENSITIVE_PATHS: # 模块级常量,默认 os.name == "nt"
cached_case_match = lookups.match_casefold_path(file_path)
lookups 是 _CachedPathLookups:小写索引 {lower(cached_path): cached_path} 在第一次未命中时构建一次
(与 realpath 别名索引同样懒构建,并用 threading.Lock 护住——walk 现在跑在工作线程里),之后每次未命中
只做一次字典查询。
_CASE_INSENSITIVE_PATHS 提成模块级常量的原因:这条分支在 Linux 上原本被 os.name == 'nt' 短路、没有任何
测试覆盖;现在测试可以 monkeypatch 该常量,在 Linux 上真实执行这条分支。
待办
- 消除 O(N×M):改成懒构建的小写索引,查询降为 O(1)。
- 补回归测试:
tests/services/test_model_scanner.py::test_reconcile_case_fold_fallback_is_indexed_not_linear(缓存路径与磁盘仅大小写不同、realpath 别名不命中 → 断言条目保留、不重新处理、索引只构建一次)。 - 回填本文件。
- (可选,纯代码瘦身)在 Windows 上确认 realpath 别名匹配是否已覆盖全部情形;若确认该分支不可达, 可以整体删掉这一层。它现在的成本已经可以忽略,删除不再是性能问题。
验证方法(可选,Windows)
- 构造"缓存路径与磁盘真实大小写不一致"的场景(改过盘符大小写、迁移过
settings.json与持久化缓存),点 Refresh。 - 日志判据:
Cache reconciliation completed in X seconds. Added 0, removed 0 models.,且没有Found N new files to process/Processing <path>。 - 跑测试:
python -m pytest tests/services/test_model_scanner.py -k reconcile。
已完成(历史,供对照)
2026-09-11 那轮清理里在 Linux(5 万文件库)验证过的部分:
cached_real_paths别名映射改为首次未命中时懒构建(原来每次 Refresh 都对全部缓存条目算一次 realpath)。- 每个文件的
realpath移到精确命中检查之后(原来对每个文件都算,命中即丢弃)。 get_model_roots()在新增文件处理阶段只快照一次(原来每个新文件重读一次)。- 全量去重 pass 加了 O(1) 前置判断(
cached_size_before != len(cached_paths) or total_added > 0)。
结果:零变更 Refresh 5 万文件 ~1400 ms → ~120 ms;根目录顺序/符号链接别名翻转场景仍是
re-processed=0。
2026-10-06 追加:walk 阶段的并发与进度
同一次改动还做了两件事(与大小写分支无关,但都动到了同一段 walk 循环,故一并记录):
- walk 循环抽成同步函数
_walk_root_for_reconcile(),并按设备分组 (_root_device_key()/_group_roots_by_device())在工作线程里并行执行:同一设备内的 root 仍按配置顺序 串行(保证目录认领与去重的确定性),不同设备之间才并行。结果回到事件循环后按配置的 root 顺序合并, 因此"同一个文件可达多条业务路径时谁胜出"与并发完成顺序无关。 - walk 阶段按 root 广播进度:
_ReconcileWalkTracker以「该 root 的缓存条目数」为权重估算进度(真实文件数 只有走完才知道),进度条把 walk 记为 0-50%,新增文件处理阶段顺延为 50-99%,两段之间不会回退。