Struct grebedb::Options

pub struct Options {
    pub open_mode: OpenMode,
    pub keys_per_node: usize,
    pub page_cache_size: usize,
    pub file_locking: bool,
    pub file_sync: SyncOption,
    pub automatic_flush: bool,
    pub automatic_flush_threshold: usize,
    pub compression_level: CompressionLevel,
}

Database configuration options.

Fields

open_mode: OpenMode

Option when opening a database. Default: LoadOrCreate.

keys_per_node: usize

Maximum number of keys-value pairs per node. Default: 1024.

This value specifies the threshold when a tree node is considered full. When a node is full, it is split into two and the tree is rebalanced.

A page contains a single node and a page is stored on disk as one file.

This option shouldn’t be changed without making performance and resource usage benchmarks.

page_cache_size: usize

Maximum number of pages held in memory cache. Default: 64.

The cache is used to store frequently accessed pages for reducing disk operations.

If memory usage is too high, consider decreasing this value first.

file_locking: bool

Whether to use file locking to prevent corruption by multiple processes. Default: true.

file_sync: SyncOption

Level of file synchronization to increase durability on disk file systems. Default: Data

automatic_flush: bool

Whether to flush the data to the file system periodically when a database operation is performed. Default: true.

When true, data is flushed when the database is dropped or when enough modifications accumulate. Setting this option to false allows you to manually persist changes at more optimal points.

There is no background maintenance thread that does automatic flushing; automatic flushing occurs when a database modifying function, such as put() or remove(), is called.

automatic_flush_threshold: usize

Number of modifications required for automatic flush to be considered. Default: 2048

When the threshold is reached after 300 seconds, or the threshold × 2 is reached after 60 seconds, a flush is scheduled to be performed on the next modification.

compression_level: CompressionLevel

Compression level for each page. Default: Low.

Trait Implementations

impl Clone for Options

fn clone(&self) -> Options

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Options

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

Formats the value using the given formatter.

impl Default for Options

fn default() -> Self

Returns the “default value” for a type.