Struct IqdbConfig 

pub struct IqdbConfig { /* private fields */ }

Construction-time configuration for an Iqdb handle.

Build one with IqdbConfig::new and chain the optional overrides. Pass it to Iqdb::open_in_memory_with or Iqdb::open_with.

Examples

use iqdb::{CacheConfig, DistanceMetric, IndexKind, IqdbConfig, IvfConfig};

let cfg = IqdbConfig::new(64, DistanceMetric::Euclidean)
    .index(IndexKind::Ivf(IvfConfig::default().with_n_clusters(256)))
    .cache(CacheConfig::new().capacity(10_000));

assert_eq!(cfg.dim(), 64);
assert_eq!(cfg.metric(), DistanceMetric::Euclidean);

Implementations

impl IqdbConfig

pub fn new(dim: usize, metric: DistanceMetric) -> Self

Start a config for a dim-dimensional database compared under metric. Defaults to an exact IndexKind::Flat index with no cache.

Examples

use iqdb::{DistanceMetric, IqdbConfig};

let cfg = IqdbConfig::new(3, DistanceMetric::Cosine);
assert_eq!(cfg.dim(), 3);

pub fn index(self, kind: IndexKind) -> Self

Select the index implementation (and its tuning).

Examples

use iqdb::{DistanceMetric, HnswConfig, IndexKind, IqdbConfig};

let cfg = IqdbConfig::new(128, DistanceMetric::Cosine)
    .index(IndexKind::Hnsw(HnswConfig::default().with_m(32)));
assert!(matches!(cfg.index_kind(), IndexKind::Hnsw(_)));

pub fn cache(self, cache: CacheConfig) -> Self

Wrap searches in a result cache with the given configuration. Without this call the database is uncached (correct, just not memoized).

Examples

use iqdb::{CacheConfig, DistanceMetric, IqdbConfig};

let cfg = IqdbConfig::new(16, DistanceMetric::Cosine)
    .cache(CacheConfig::new().capacity(4_096));
assert!(cfg.is_cached());

pub fn fsync(self, policy: FsyncPolicy) -> Self

Set the write-ahead-log fsync cadence for the durable, file-backed path. Ignored by an in-memory database.

The default, FsyncPolicy::Always, makes every acknowledged write durable before it returns. FsyncPolicy::Periodic bounds the un-synced window for throughput; FsyncPolicy::Never is for tests and tmpfs-backed paths only.

Examples

use iqdb::{DistanceMetric, FsyncPolicy, IqdbConfig};
use std::time::Duration;

let cfg = IqdbConfig::new(16, DistanceMetric::Cosine)
    .fsync(FsyncPolicy::Periodic(Duration::from_millis(50)));

pub fn compression(self, compression: Compression) -> Self

Set the snapshot compression for the durable, file-backed path. Ignored by an in-memory database.

Compression::Zstd and Compression::Lz4 require the matching zstd / lz4 cargo feature; opening with one whose feature is not compiled in fails with Error::Persist. The default is Compression::None.

Examples

use iqdb::{Compression, DistanceMetric, IqdbConfig};

let cfg = IqdbConfig::new(16, DistanceMetric::Cosine)
    .compression(Compression::Zstd { level: 3 });

pub fn dim(&self) -> usize

The configured dimensionality.

pub fn metric(&self) -> DistanceMetric

The configured distance metric.

pub fn index_kind(&self) -> IndexKind

The configured index kind.

pub fn is_cached(&self) -> bool

true if a result cache is configured.

Trait Implementations

impl Clone for IqdbConfig

fn clone(&self) -> IqdbConfig

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for IqdbConfig

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.