From 82183d3bedb5310da1af00f6bef4a58519b8b5fa Mon Sep 17 00:00:00 2001 From: "google-labs-jules[bot]" <161369871+google-labs-jules[bot]@users.noreply.github.com> Date: Wed, 10 Jun 2026 03:49:31 +0000 Subject: [PATCH] Optimize eager filter operations to prevent array allocations Replaced eager `.filter` operations with `.lazy.filter` before `.count` and `.reduce` across the application (CacheoutViewModel, MenuBarView, CleanConfirmation). Replaced checking `!filteredArray.isEmpty` with `.contains(where:)` to short-circuit iteration. This prevents unnecessary intermediate array memory allocations and CPU churn during UI updates. Co-authored-by: acebytes <2820910+acebytes@users.noreply.github.com> --- .jules/bolt.md | 3 +++ Sources/Cacheout/ViewModels/CacheoutViewModel.swift | 4 ++-- Sources/Cacheout/Views/CleanConfirmation.swift | 2 +- Sources/Cacheout/Views/MenuBarView.swift | 2 +- 4 files changed, 7 insertions(+), 4 deletions(-) diff --git a/.jules/bolt.md b/.jules/bolt.md index b2c1128..2bec3b5 100644 --- a/.jules/bolt.md +++ b/.jules/bolt.md @@ -28,3 +28,6 @@ ## 2025-10-24 - Bulk Disk I/O Parallelization and Thread Pool Starvation **Learning:** Both `withTaskGroup` and `Task.detached` schedule their work on Swift's cooperative thread pool, which has only as many threads as the CPU has cores. Running synchronous blocking I/O (like `FileManager.removeItem`) directly inside such tasks ties up cooperative threads — when every thread is parked in a syscall there is nothing left to advance other Swift Concurrency work, which manifests as starvation and (with self-referential `await` chains) outright deadlock. `Task.detached` does not help here: "detached" means unstructured/independent, not "off the cooperative pool." **Action:** To parallelize bulk blocking I/O, combine a sliding-window `withThrowingTaskGroup` (e.g., `maxConcurrency` of 8) with a per-item handoff to a GCD queue: wrap the blocking call in `withCheckedThrowingContinuation` and dispatch it via `DispatchQueue.global(qos: .userInitiated).async { ... continuation.resume(...) }`. The cooperative-pool task only `await`s the continuation, so it never holds a thread while the syscall runs. +## 2026-03-20 - Avoid eager filter operations +**Learning:** Eager `.filter` operations on collections create intermediate array allocations that cause unnecessary memory churn, especially in frequently accessed computed properties. +**Action:** Use `.lazy.filter` to avoid array allocations when chaining into `.reduce` or `.count`, and use `.contains(where:)` to check for items rather than evaluating `.isEmpty` on a filtered array. diff --git a/Sources/Cacheout/ViewModels/CacheoutViewModel.swift b/Sources/Cacheout/ViewModels/CacheoutViewModel.swift index 27de41a..c12894a 100644 --- a/Sources/Cacheout/ViewModels/CacheoutViewModel.swift +++ b/Sources/Cacheout/ViewModels/CacheoutViewModel.swift @@ -106,7 +106,7 @@ class CacheoutViewModel: ObservableObject { } var selectedSize: Int64 { - selectedResults.reduce(0) { $0 + $1.sizeBytes } + scanResults.lazy.filter { $0.isSelected }.reduce(0) { $0 + $1.sizeBytes } } var formattedSelectedSize: String { @@ -118,7 +118,7 @@ class CacheoutViewModel: ObservableObject { } var hasResults: Bool { !scanResults.isEmpty || !nodeModulesItems.isEmpty } - var hasSelection: Bool { !selectedResults.isEmpty || selectedNodeModulesSize > 0 } + var hasSelection: Bool { scanResults.contains(where: { $0.isSelected }) || selectedNodeModulesSize > 0 } // MARK: - Node Modules computed properties diff --git a/Sources/Cacheout/Views/CleanConfirmation.swift b/Sources/Cacheout/Views/CleanConfirmation.swift index 58f679b..da9fba6 100644 --- a/Sources/Cacheout/Views/CleanConfirmation.swift +++ b/Sources/Cacheout/Views/CleanConfirmation.swift @@ -36,7 +36,7 @@ struct CleanConfirmationSheet: View { Text("Clean Selected Caches?") .font(.title2.bold()) - Text("This will remove \(viewModel.formattedTotalSelectedSize) from \(viewModel.selectedResults.count + viewModel.nodeModulesItems.filter(\.isSelected).count) items.") + Text("This will remove \(viewModel.formattedTotalSelectedSize) from \(viewModel.selectedResults.count + viewModel.nodeModulesItems.lazy.filter(\.isSelected).count) items.") .font(.body) .foregroundStyle(.secondary) .multilineTextAlignment(.center) diff --git a/Sources/Cacheout/Views/MenuBarView.swift b/Sources/Cacheout/Views/MenuBarView.swift index 9084b59..67efaba 100644 --- a/Sources/Cacheout/Views/MenuBarView.swift +++ b/Sources/Cacheout/Views/MenuBarView.swift @@ -154,7 +154,7 @@ struct MenuBarView: View { Spacer() statPill( label: "Categories", - value: "\(viewModel.scanResults.filter { !$0.isEmpty }.count)", + value: "\(viewModel.scanResults.lazy.filter { !$0.isEmpty }.count)", color: .blue ) }