Perfetto v45.0

v45.0 - 2024-05-09:
  Trace Processor:
    * Optimised single column `DISTINCT` queries.
    * Optimised `LIMIT` and `OFFSET` queries.
  SQL Standard library:
    * Improved support for querying startups on Android 9 (API level 28) and
      below. Available in `android.startup.startups` module.
    * Added tables for querying "Time To Initial Display" and "Time To Full
      Display" metrics for app startups. Available in new module
      `android.startup.time_to_display`.
    * Added table for querying hardware power rail counters in new
      `android.power_rails` module.
  UI:
    * Add tracks to the list of searchable items.
    * Use mipmaps to improve track query performance on large traces.
    * Fix slow scrolling bug in ftrace explorer tab on low DPI machines.
    * Overhaul track decider queries to improve trace load times.
    * Add track
    * Tidy up command names & remove some example ones.
    * Remove arg auto-completion in pivot table.
    * Show dominator tree views by default.
    * Fix counter event selection off-by-one error.
    * Add viewport control to the plugin API.
    * Sticky track titles to improve track button accessibility in tall tracks.
    * A handful of small bugfixes.
  SDK:
    * The TRACE_EVENT macro used to reject `const char *` event names: either
      `StaticString` or `DynamicString` needed to be specified. In the last year
      (since https://r.android.com/2494614), TRACE_EVENT mistakenly accepted
      `const char *` as an event name. This has been fixed now. In case your
      code fails to compile,
      https://perfetto.dev/docs/instrumentation/track-events#dynamic-event-names
      explains how to fix the problem.

Perfetto v44.0

v44.0 - 2024-04-10:
  Trace Processor:
    * New modules added to standard library: `frames.timeline`,
      `frame.per_frame_metrics`, `sched.time_in_state`.
  UI:
    * Per-cpu scheduling tracks now distinguish real-time priority threads with
      a hatched pattern and name prefix. Based on priority during switch-in.
    * Added ftrace event cropping for traces recorded by perfetto v44+.
      Events are ignored if they precede the earliest timestamp covered by all
      per-cpu data streams. This should significantly improve the presentation
      of RING_BUFFER traces, removing artifacts such as never-ending slices
      starting at the beginning of the trace.
    * Significantly improved trace load times.
    * Improved counter track view modes, including log scale, expanded view, and
      the ability for plugin authors to link scales of several counter tracks
      together.
    * Add dominated size and objects to Java heap graph view.
      Added hotkey Q to open and close bottom drawer.
    * Fixed bug where timeline header and tracks could become horizontally
      misaligned when using browser zoom.
    * Fixed crash when hot-reloading Sass during development.
    * Fixed bug where crashed debug tracks could not be closed.
    * Fixed missing flame graph details for area selections.
    * Consistent reporting of durations for incomplete slices.
    * Switch to using prettier for formatting TS & Sass instead of ESLint.
  SDK:
    * "track_event" categories are disabled by default in the C API, if they
      don't match anything in the data source config. This behavior differs from
      the C++ API. Configs should include either `enabled_categories: "*"` or
      `disable_categories: "*"` to explicitly specify the desired behavior that
      work both for C and C++.

Perfetto v43.1

https://android.googlesource.com/platform/external/perfetto/+/refs/tags/v43.1
https://github.com/google/perfetto/tree/v43.1

v43.1 - 2024-03-05:
  Tracing service and probes:
    * Cherry-pick of https://r.android.com/2988674, which fixes the android x86
      standalone build.

v43.0 - 2024-03-05:
  Tracing service and probes:
    * Buffers marked as `transfer_on_clone` will be flushed independently when
      cloning.
    * ftrace: added drain_buffer_percent option to read kernel ring buffer
      based on occupancy in addition to existing periodic reads. Requires Linux
      kernel v6.1+.
    * ftrace: changed default kernel per-cpu ring buffer sizes if a config
      doesn't request an explicit size via buffer_size_kb. Added
      buffer_size_lower_bound option that lets the service choose a bigger ring
      buffer size than requested.
    * "linux.process_stats" data source: added options to record: process age,
      time spent running in userspace, and time spent running in kernel mode,
      using /proc/pid/stat. See "record_process_age" and
      "record_process_runtime" options.
  Trace Processor:
    * Added `decompress_packets` mode to the traceconv tool.
    * Support memory mapped file access on Windows.
    * Deprecated `common` standard library module, it will be removed by v45.
      Some of the functionality have been migrated to other parts of standard
      library.
  UI:
    * Added a "defaultPlugins" list to allow control over which plugins are
      enabled by default.
    * Added a feature to allow enabling/disabling plugins permanently from the
      plugins page.
    * Added plugin load times to the plugin page.
    * Added scrolling to the pinned track area.
    * Added commands for expanding and closing all tracks.
    * Added {expand,collapse}GroupsByPredicate to plugin API.
    * Added SimpleSliceTrack & SimpleCounterTrack which have the same
      functionality of debug tracks but may be added on trace load from within
      plugins.
    * Added naive track crash containment, which means tracks that crash should
      not crash the entire UI.
    * Don't render "idle" kernel thread slices in thread state tracks.
    * Fixed crash when using autofill in text inputs in chrome.
    * Fixed bug where "incomplete" slices were sometimes not rendered.
    * Fixed crash when calls to CacheStorage fail via promise rejection.
    * Fixed bug causing slices to occasionally disappear in tracks v2.
    * Fixes crash in tracksV2 when visible window is negative.
    * Fix bug when toggling the sidebar without a trace loaded would either
      crash the UI or simply not work.
    * Various TabsV2 QoL improvements.
    * Various AndroidLongBatteryTracing plugin improvements.

v42.0 - 2024-02-02:
  Tracing service and probes:
    * Linux/Android: kernel scheduling data (sched_switch and sched_waking
      ftrace events) is now serialised in a more compact format by default
      (previously required setting ftrace_config.compact_sched.enabled).
  UI:
    * Added "Realtime (Trace TZ)" timestamp formatting option to see timestamps
      in the local time of the traced device. It requires recent versions of the
      tracing service which set the system_info.timezone_off_mins field.
    * Added tab support to the plugin API.
    * Added a plugin to improve visualization of Android power traces containing
      ODPM (on-device power rail monitor) data.
    * Added support to attach the UI via ?rpc_port=1234 to multiple instances of
      trace_processor --httpd --http-port=1234 (see UI docs).
    * Fixed OOM detection message on in-memory tables.
    * Fixed rendering of events at the every beginning and end of the trace.
    * Fixed rendering of low density slices.
    * Fixed bug in filterVisibleSlices (Thanks to Liangliang Sui).
  SDK:
    * Fixed a bug that would cause DataSource::OnStop to be called twice upon
      service disconnection with HandleStopAsynchronously().
    * Fixed a long standing bug that caused the last TracePacket for every
      sequence to be lost during scraping, for data sources that do not support
      flushing. The fix works with old versions of the tracing service.

Perfetto v42.0

v42.0 - 2024-02-02:
  Tracing service and probes:
    * Linux/Android: kernel scheduling data (sched_switch and sched_waking
      ftrace events) is now serialised in a more compact format by default
      (previously required setting ftrace_config.compact_sched.enabled).
  UI:
    * Added "Realtime (Trace TZ)" timestamp formatting option to see timestamps
      in the local time of the traced device. It requires recent versions of the
      tracing service which set the system_info.timezone_off_mins field.
    * Added tab support to the plugin API.
    * Added a plugin to improve visualization of Android power traces containing
      ODPM (on-device power rail monitor) data.
    * Added support to attach the UI via ?rpc_port=1234 to multiple instances of
      trace_processor --httpd --http-port=1234 (see UI docs).
    * Fixed OOM detection message on in-memory tables.
    * Fixed rendering of events at the every beginning and end of the trace.
    * Fixed rendering of low density slices.
    * Fixed bug in filterVisibleSlices (Thanks to Liangliang Sui).
  SDK:
    * Fixed a bug that would cause DataSource::OnStop to be called twice upon
      service disconnection with HandleStopAsynchronously().
    * Fixed a long standing bug that caused the last TracePacket for every
      sequence to be lost during scraping, for data sources that do not support
      flushing. The fix works with old versions of the tracing service.

Perfetto v41.0

v41.0 - 2023-01-02:
  Tracing service and probes:
    * Added support for ADB_SERVER_SOCKET in the websocket bridge.
    * Added support for reading Pressure Stall Information (PSI) from the kernel.
  Trace Processor:
    * Added capability to control trace processor using stdin/stdout when using
      shell binary. This acts as a simpler alternative to the existing HTTP
      control API.
    * Fixed multiple edge-case issues in RestoreInitialTables.
  SDK:
    * Fixed a long standing bug that caused the last TrackEvent event for each
      thread to be lost during scraping. The fix works with old versions of the
      tracing service.

Perfetto v40.0

v40.0 - 2023-12-04:
  Tracing service and probes:
    * Added support for collecting battery voltage from the Android Power HAL.
    * Added support for emitting machine id from producers on remote hosts.
  Trace Processor:
    * Added of flow id from trace as a column in the flow table.
    * Fixed computation of trace_bounds table when using UI native acceleration.
  UI:
    * Switched to use "v2" querying and rendering system for tracks by default.

Perfetto v39.0

v39.0 - 2023-11-15:
  Tracing service and probes:
    * Added reporting of TZ offset under system_info.timezone_off_mins .
    * Added no_flush option to DataSourceDescriptor to avoid unnecessary IPC
      roundtrips to flush data sources like track_event that rely uniquely on
      server-side scraping.
    * Added support for running on Linux & Android systems configured with 16K
      pagetables.
  Trace Processor:
    * New android_boot metric.
    * Added new PerfettoSQL syntax (CREATE PERFETTO VIEW) for adding schemas to views.
    * Support perf.data import format.
    * Add dvfs and cpu_idle to stdlib.
  UI:
    * Add a new type of debug tracks: counter.
    * Improved visualization of timestamps for durations.

Perfetto v38.0

v38.0 - 2023-10-10:
  Tracing service and probes:
    * Added capability to transfer and clear buffers on CLONE_SNAPSHOT.
    * Added new service for relaying IPC messages from local producers to a
      remote tracing instance.
  Trace Processor:
    * Added new PerfettoSQL syntax (INCLUDE PERFETTO MODULE) for including
      tables/views/functions defined in SQL modules.
    * Added new PerfettoSQL syntax (CREATE PERFETTO TABLE) for defining analytic
      tables in SQL.
    * Added new PerfettoSQL syntax (CREATE PERFETTO MACRO) for defining macros
      in SQL.
    * Added TO_REALTIME function to convert timestamps to the realtime clock.
    * Added support for parsing binder_command and binder_return events.
  UI:
    * Added support for zooming when using deep-links.
    * Added track for displaying screenshots in traces.
    * Added support for displaying UTC timestamps.
    * Added capability to list, search and debug plugin tracks.
    * Added plugins with commands for pinning tracks for latency and large
      screen debugging in Android.

Perfetto v37.0

v37.0 - 2023-08-10:
  Tracing service and probes:
    * Fixed a bug which would cause sessions cloned with CLONE_SNAPSHOT to not
      inherit the trace filtering config.
    * Fixed a bug that would cause flushes to be acked prematurely in
      traced_probes if the android.package_list data source is present.
  SDK:
    * Fix build with MSVC.
  UI:
    * Added command palette (CTRL/Meta+Shift+P).
    * Added grouping of global tracks into groups to reduce visual pollution.
    * Added ability to toggle timestamps between trace / boot / wall time.
    * Added recording UI for callstack sampler.
    * Added "Viz" page to run chart query results with Vega-Lite.
    * Highlight debuggable apps, which might have worse performance
      characteristics, with a chip on the corresponding tracks.
  Misc:
    * master -> main branch migration. HEAD is now main, master is for now a
      mirror and will become a stale frozen snapshot.

Perfetto v36.1

v36.1 - 2023-07-06:
  Trace Processor:
    * Fix compile on Windows.

v36.0 - 2023-07-05:
  Tracing service and probes:
    * Fixed unnecessary reads of thread files /proc when scraping process names.
  Trace Processor:
    * Rewrote filtering engine to be significantly faster on a wide range of
      common queries.
    * Significantly improved quality of PerfettoSQL error messages.
    * Added API to retrieve last executed statement from iterator.
    * Added support for filtering rows by a regex.
  UI:
    * Fixed flow events working for async tracks.
    * Added table viewer for slice-like tables.
  SDK:
    * Reduce binary size impact of macro and template expansions.