From 2dfb5da16b97a6c12e01977af5b5188522178a4e Mon Sep 17 00:00:00 2001 From: Stefan Boberg Date: Mon, 20 Apr 2026 21:50:41 +0200 Subject: zen trace analysis support (#945) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Integrates the **tourist** trace analysis library and builds a full `zen trace` command suite for working with Unreal Engine `.utrace` files. ### Trace analysis library (`thirdparty/tourist/`) - Adds the tourist library as a third-party dependency with three modules: **foundation** (platform primitives, memory, scheduling), **trace** (UE Trace protocol decoding), and **analysis** (event dispatching and analyzer framework). - Cross-platform support for Windows, Linux, and macOS. ### `zen trace` CLI commands (`src/zen/cmds/`, `src/zen/trace/`) - **`zen trace analyze`** — Summarize a `.utrace` file: session metadata, thread inventory, command line + build configuration, CPU profiling scopes, timing, event rates, log messages, and (with symbols) memory allocation metrics including live-allocs dumps, callstack-keyed aggregation, and allocation churn. Optional HTML output for memory reports. - **`zen trace inspect`** — Dump the event schema (declared types, fields, sizes) from a trace file. - **`zen trace trim`** — Extract a time-window from a trace into a new `.utrace` file. - **`zen trace serve`** — Launch a local HTTP server hosting an interactive trace viewer; opens in the default browser. ### Symbolication (`src/zen/trace/symbol_resolver.*`, `thirdparty/raw_pdb/`) - Pluggable resolver with multiple backends: `pdb` (in-tree raw_pdb), `dbghelp` (Windows), `llvm-symbolizer` (all platforms), `atos` (macOS). An `auto` backend picks the best available tool per platform. - Microsoft Symbol Server support: downloads PDBs on demand using a redirect-aware HTTP client. - Local PDB cache keyed by image GUID preserves symbols across binary recompilation. - Callstack trimming heuristic strips UE internal noise from reports. - Binary analysis cache (`.ucache_z`) avoids re-resolving the same trace. ### Interactive trace viewer (`src/zen/frontend/html/`, `src/zen/trace/trace_viewer_service.*`) - Timeline: scope-level detail, horizontal zoom/pan, vertical scrolling, viewport-driven loading with pre-computed LOD for responsive navigation of large traces. - Thread grouping (collapsible sidebar sections) synthesized from name suffixes, natural sort order, visual distinction between lane threads and OS threads. - Bookmark and region annotations; region categories with per-category toggles; bookmark marker toggle in the toolbar. - Filterable Logs tab showing captured `UE_LOG` output. - Stats tab with per-scope aggregate statistics. - Memory tab with interactive allocation analysis and an allocation size histogram. - CsvProfiler event parsing and chart UI. ### Other in-branch supporting changes - **Cross-platform browser launcher** (`browser_launcher.{h,cpp}`) used by `trace serve`. - **`ReciprocalU64`** fast 64-bit integer division (zencore/intmath) for trace analyzers. - **`parallelsort`** cross-platform parallel sort helper (zenutil). - Frontend zip build rule so the viewer's HTML assets are bundled into `zen.exe`. - `/Zo` flag for better optimized debug info on Windows release builds. - `trace-tests.cpp` in the `zen-test` harness (harness itself landed on main via #985). --- src/zen/cmds/trace_cmd.cpp | 89 ---------------------------------------------- 1 file changed, 89 deletions(-) delete mode 100644 src/zen/cmds/trace_cmd.cpp (limited to 'src/zen/cmds/trace_cmd.cpp') diff --git a/src/zen/cmds/trace_cmd.cpp b/src/zen/cmds/trace_cmd.cpp deleted file mode 100644 index 54c0f080d..000000000 --- a/src/zen/cmds/trace_cmd.cpp +++ /dev/null @@ -1,89 +0,0 @@ -// Copyright Epic Games, Inc. All Rights Reserved. - -#include "trace_cmd.h" -#include -#include -#include - -using namespace std::literals; - -namespace zen { - -TraceCommand::TraceCommand() -{ - m_Options.add_options()("h,help", "Print help"); - m_Options.add_option("", "u", "hosturl", kHostUrlHelp, cxxopts::value(m_HostName)->default_value(""), ""); - m_Options.add_option("", "s", "stop", "Stop tracing", cxxopts::value(m_Stop)->default_value("false"), ""); - m_Options.add_option("", "", "host", "Start tracing to host", cxxopts::value(m_TraceHost), ""); - m_Options.add_option("", "", "file", "Start tracing to file", cxxopts::value(m_TraceFile), ""); -} - -TraceCommand::~TraceCommand() = default; - -void -TraceCommand::Run(const ZenCliOptions& GlobalOptions, int argc, char** argv) -{ - ZEN_UNUSED(GlobalOptions); - - if (!ParseOptions(argc, argv)) - { - return; - } - - m_HostName = ResolveTargetHostSpec(m_HostName); - - if (m_HostName.empty()) - { - throw OptionParseException("Unable to resolve server specification", m_Options.help()); - } - - zen::HttpClient Http = CreateHttpClient(m_HostName); - - if (m_Stop) - { - if (zen::HttpClient::Response Response = Http.Post("/admin/trace/stop"sv)) - { - ZEN_CONSOLE("OK: {}", Response.ToText()); - } - else - { - Response.ThrowError("Trace stop failed"); - } - return; - } - - std::string StartArg; - if (!m_TraceHost.empty()) - { - StartArg = fmt::format("host={}", m_TraceHost); - } - else if (!m_TraceFile.empty()) - { - StartArg = fmt::format("file={}", m_TraceFile); - } - - if (!StartArg.empty()) - { - if (zen::HttpClient::Response Response = Http.Post(fmt::format("/admin/trace/start?{}"sv, StartArg))) - { - ZEN_CONSOLE("OK: {}", Response.ToText()); - } - else - { - Response.ThrowError("Trace start failed"); - } - } - else - { - if (zen::HttpClient::Response Response = Http.Get("/admin/trace"sv)) - { - ZEN_CONSOLE("OK: {}", Response.ToText()); - } - else - { - Response.ThrowError("Trace status failed"); - } - } -} - -} // namespace zen -- cgit v1.2.3