v48.0 - 2024-10-11:
Tracing service and probes:
* Improved accuracy of ftrace event cropping when there are multiple
concurrent tracing sessions. See `previous_bundle_end_timestamp` in
ftrace_event_bundle.proto.
* Increased watchdog timeout to 180s from 30s to make watchdog crashes
much less likely when system is under heavy load.
SQL Standard library:
* Improved CPU cycles calculation in `linux.cpu.utilization` modules:
`process`, `system` and `thread` by fixing a bug responsible for too high
CPU cycles values.
* Introduces functions responsible for calculating CPU cycles with
breakdown by CPU, thread, process and slice for a given interval.
* Added `linux.perf.samples` module for easy querying of perf samples
in traces.
* Added `stacks.cpu_profiling` module for easy querying of all CPU
profiling data in traces.
Trace Processor:
* Added (partial) support for the Gecko (Firefox) JSON profiler format.
Parsing is optimized for CPU profiling collected with `perf` and converted
to the Gecko format. Only parsing of samples is supported; parsing of
markers and any other features (e.g. colours) is *not* supported.
* Added (partial) suppoort for the perf script text format from both perf
and simpleperf. Only parsing files with the default formating or with pids
included (i.e. `-F +pid`) is supported. Any other formatting options are
*not* supported.
* Added support for parsing non-streaming ART method tracing format.
* Added support for parsing GZIP files with multiple gzip streams.
* Added support for parsing V8 CPU profling samples from proto traces.
* Renamed Trace Processor's C++ method `RegisterSqlModule()` to
`RegisterSqlPackage()`, which better represents the module/package
relationship. Package is the top level grouping of modules, which are
objects being included with `INCLUDE PERFETTO MODULE`.
`RegisterSqlModule()` is still available and runs `RegisterSqlPackage()`.
`RegisterSqlModule()` will be deprecated in v50.0.
UI:
* Scheduling wakeup information now reflects whether the wakeup came
from an interrupt context. The per-cpu scheduling tracks now show only
non-interrupt wakeups, while the per-thread thread state tracks either
link to an exact waker slice or state that the wakeup is from an
interrupt. Older traces that are recorded without interrupt context
information treat all wakeups as non-interrupt.
* Nest global/user async tracks according to their parent/child relationship
in the trace.
* Introduced new workspace API which allows nested tracks & multiple
workspace support.
* Introduced middle ellipsis in track titles when title text is longer than
the available space, while preserving the start and end of title text &
add popup of full title text on hover.
* Fixed spurious judder issue in popups with tall content.
* Fixed bug where marker durations were not rendered on selected markers.
* Removed ChromeScrollJank V1 track (V2 should be used from now on).
* Major internal changes (affecting pugin developers and core contributors):
* Removed legacy selection types, use track event selection types going
forward for all single event selections.
* Details panels are now attached to the track rather than registered
separately.
* Introduced `registerSqlSelectionResolver`, which allow plugins to add
handlers allowing other parts of the codebase to make selection on
tracks from other plugins based on a sql table name and id.
* Changed lifetime of track instances; they are now created on trace load
by plugins and survive the lifetime of the trace, rather than getting
created and destroyed as they appear/disappear on the timeline.
* Fix circular dependencies and turn future instances into errors.
