Struct MitoRegion

pub(crate) struct MitoRegion {
    pub(crate) region_id: RegionId,
    pub(crate) version_control: Arc<VersionControl>,
    pub(crate) access_layer: AccessLayerRef,
    pub(crate) manifest_ctx: Arc<ManifestContext>,
    pub(crate) file_purger: FilePurgerRef,
    pub(crate) provider: Provider,
    last_flush_millis: AtomicI64,
    last_compaction_millis: AtomicI64,
    time_provider: Arc<dyn TimeProvider>,
    pub(crate) memtable_builder: MemtableBuilderRef,
    stats: ManifestStats,
}

Metadata and runtime status of a region.

Writing and reading a region follow a single-writer-multi-reader rule:

• Only the region worker thread this region belongs to can modify the metadata.
• Multiple reader threads are allowed to read a specific version of a region.

Fields

region_id: RegionId

Id of this region.

Accessing region id from the version control is inconvenient so we also store it here.

version_control: Arc<VersionControl>

Version controller for this region.

We MUST update the version control inside the write lock of the region manifest manager.

access_layer: AccessLayerRef

SSTs accessor for this region.

manifest_ctx: Arc<ManifestContext>

Context to maintain manifest for this region.

file_purger: FilePurgerRef

SST file purger.

provider: Provider

The provider of log store.

last_flush_millis: AtomicI64

Last flush time in millis.

last_compaction_millis: AtomicI64

Last compaction time in millis.

time_provider: Arc<dyn TimeProvider>

Provider to get current time.

memtable_builder: MemtableBuilderRef

Memtable builder for the region.

stats: ManifestStats

manifest stats

Implementations

impl MitoRegion

pub(crate) async fn stop(&self)

Stop background managers for this region.

pub(crate) fn metadata(&self) -> RegionMetadataRef

Returns current metadata of the region.

pub(crate) fn primary_key_encoding(&self) -> PrimaryKeyEncoding

Returns primary key encoding of the region.

pub(crate) fn version(&self) -> Arc<Version>

Returns current version of the region.

pub(crate) fn last_flush_millis(&self) -> i64

Returns last flush timestamp in millis.

pub(crate) fn update_flush_millis(&self)

Update flush time to current time.

pub(crate) fn last_compaction_millis(&self) -> i64

Return last compaction time in millis.

pub(crate) fn update_compaction_millis(&self)

Update compaction time to now millis.

pub(crate) fn region_dir(&self) -> &str

Returns the region dir.

pub(crate) fn is_writable(&self) -> bool

Returns whether the region is writable.

pub(crate) fn is_flushable(&self) -> bool

Returns whether the region is flushable.

pub(crate) fn is_downgrading(&self) -> bool

Returns whether the region is downgrading.

pub(crate) fn is_follower(&self) -> bool

Returns whether the region is readonly.

pub(crate) fn state(&self) -> RegionRoleState

Returns the state of the region.

pub(crate) fn set_role(&self, next_role: RegionRole)

Sets the region role state.

pub(crate) fn set_altering(&self) -> Result<()>

Sets the altering state. You should call this method in the worker loop.

pub(crate) fn set_dropping(&self) -> Result<()>

Sets the dropping state. You should call this method in the worker loop.

pub(crate) fn set_truncating(&self) -> Result<()>

Sets the truncating state. You should call this method in the worker loop.

pub(crate) fn set_editing(&self) -> Result<()>

Sets the editing state. You should call this method in the worker loop.

pub(crate) async fn set_role_state_gracefully( &self, state: SettableRegionRoleState, )

Sets the region to readonly gracefully. This acquires the manifest write lock.

pub(crate) fn switch_state_to_writable(&self, expect: RegionLeaderState)

Switches the region state to RegionRoleState::Leader(RegionLeaderState::Writable) if the current state is expect. Otherwise, logs an error.

pub(crate) fn region_statistic(&self) -> RegionStatistic

Returns the region statistic.

fn estimated_wal_usage(&self, memtable_usage: u64) -> u64

Estimated WAL size in bytes. Use the memtables size to estimate the size of wal.

fn compare_exchange_state( &self, expect: RegionLeaderState, state: RegionRoleState, ) -> Result<()>

Sets the state of the region to given state if the current state equals to the expected.

Trait Implementations

impl Debug for MitoRegion

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

Formats the value using the given formatter.