Documentation
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Overview ¶
Package compress wraps zstd/lz4 block compression and defines the composable codec-chain type (preprocessor → general compressor) used to reach 0.4–0.8 bytes/point (DESIGN.md §3.3, §14 M0).
A [Chain] is a sequence of a column-specific preprocessor (from [chunk]) followed by a general compressor (ZSTD or LZ4). Cold-tier recompression is just a different chain over the same parts. The wrappers are append-style (Compress(dst, src) []byte / Decompress(dst, src) []byte) and use pooled encoders/ decoders to avoid per-call allocation.
Index ¶
Constants ¶
const ( // FlagRaw means the payload is stored uncompressed. FlagRaw byte = 0x00 // FlagCompressed means the payload is algorithm-compressed. FlagCompressed byte = 0x01 )
Flag bytes for the compressed-block format.
Variables ¶
This section is empty.
Functions ¶
This section is empty.
Types ¶
type Compressor ¶
type Compressor struct {
// contains filtered or unexported fields
}
Compressor is a pooled, append-style compressor. It is safe for concurrent use (each Compress/Decompress call borrows a pooled encoder/decoder).
func NewCompressor ¶
func NewCompressor(alg Algorithm, level Level) *Compressor
NewCompressor returns a Compressor for the given algorithm and level. Level is only meaningful for ZSTD; LZ4 ignores it.
func (*Compressor) Algorithm ¶
func (c *Compressor) Algorithm() Algorithm
Algorithm returns the compressor's algorithm.
func (*Compressor) Compress ¶
func (c *Compressor) Compress(dst, src []byte) []byte
Compress appends the compressed form of src to dst and returns the extended slice. If compression does not reduce the size (rare for small inputs), the raw bytes are stored with a 1-byte prefix FlagRaw.
func (*Compressor) Decompress ¶
func (c *Compressor) Decompress(dst, src []byte) ([]byte, error)
Decompress appends the decompressed form of src to dst and returns the extended slice. src must start with a flag byte (FlagRaw or FlagCompressed).
Source Files