Module write_opts 

Writer tuning knobs: index tile size, dictionary chunk size, zstd level and frame shape, and frequency-promoted object ids. The measurements behind the defaults are in docs/BENCHMARK.md (“Compression (0.4)”).

None of these change the file format. Every combination writes a file any reader of the same format version opens unchanged: tiles and dictionary chunks of any size are routed by their directories, zstd frames of any level or shape decode with any conformant decoder, and a promoted object is an ordinary entry of the shared dictionary section.

The settings are process-wide, like RETE_DICT_RESTART_INTERVAL: the CLI sets them once, before a build, and every writer path (the in-memory and streaming assemblers and the external build) reads the same values, so the byte-identity between those paths holds for every setting. Each knob falls back to an environment variable, then to the built-in default:

knob	env var	default
index tile budget	RETE_TILE_KIB	64 KiB
dictionary chunk budget	RETE_DICT_CHUNK_KIB	64 KiB
zstd level	RETE_ZSTD_LEVEL	9
zstd frame shape	RETE_ZSTD_FRAME (sized / stream)	sized
frequency-promoted objects	RETE_FREQUENT_OBJECTS	0 (off)

Structs

WriteOptions

A complete set of writer settings.

Enums

FrameShape

How each tile / chunk is framed by zstd.

Constants

DEFAULT_DICT_CHUNK_BYTES

Default per-chunk budget of a dictionary section body, in uncompressed bytes.

DEFAULT_TILE_BUDGET_BYTES

Default per-tile budget of an index permutation, in uncompressed bytes.

DEFAULT_ZSTD_LEVEL

Default zstd level of the writer.

MAX_BUDGET_KIB

Largest accepted tile or chunk budget (KiB). A tile is decoded whole on every touch, so very large tiles turn a point lookup into a large decode.

MIN_BUDGET_KIB

Smallest accepted tile or chunk budget (KiB). Below this the per-unit directory entry and frame header dominate.

Functions

dict_chunk_budget

The dictionary chunk budget in force (bytes).

frame_shape

The zstd frame shape in force.

frequent_objects

How many frequent object-only terms the dictionary builder promotes.

set_write_options

Replace the settings in force for this process (the CLI calls this once, from its flags, before a build). Values outside the accepted ranges are clamped.

tile_budget

The index tile budget in force (bytes).

write_options

The full set of settings in force.

zstd_level

The zstd level in force.