Crate katra_trace 

katra-trace — the Katra trace format.

A trace is a versioned, deterministic, append-only stream of records:

[magic: 8 bytes] [format_version: u32] [header_len: u32] [header: bincode]
[record_len: u32] [record: bincode(TraceRecord)] ... (repeat)

Records are Event, EpochMarker, Counter, or SessionSummary.

Determinism

• seq is monotonic; events are written in seq order.
• Timestamps are ns since profiler start (plus a wall-clock anchor in the header and in epoch markers).
• Replay can therefore re-emit a trace at exact relative timing.

Versioning discipline

• Enum layouts are serialized by variant index: append new variants at the end of any enum in katra-core.
• Any layout-affecting change bumps header::SCHEMA_HASH (computed from header::SCHEMA_STRING at compile time).
• Backward-incompatible changes bump header::FORMAT_VERSION.

Re-exports

pub use header::FORMAT_VERSION;

pub use header::SCHEMA_HASH;

pub use header::SCHEMA_STRING;

pub use header::TRACE_MAGIC;

pub use header::TraceHeader;

pub use reader::TraceReader;

pub use reader::TraceReaderError;

pub use record::TraceRecord;

pub use record::TraceSummary;

pub use verify::VerifyIssue;

pub use verify::VerifyReport;

pub use writer::TraceWriter;

pub use writer::default_header;

Modules

header

Trace header: magic, format version, schema hash, and capture metadata.

reader

Trace reader: iterates records from a trace file with validation.

record

Trace records.

verify

Trace verification: checks the invariants a well-formed trace must obey.

writer

Trace writer: appends length-prefixed bincode records to a file.