Safe Haskell	Safe-Inferred
Language	GHC2021

Database.LSMTree.Internal.Index.CompactAcc

Contents

Construction
Utility
Internal: exported for testing and benchmarking

Description

Incremental construction of a compact index yields chunks of the primary array that can be serialised incrementally.

Incremental construction is an ST computation that can be started using new, returning an IndexCompactAcc structure that accumulates internal state. appending new pages to the IndexCompactAcc might yield Chunks. Incremental construction can be finalised with unsafeEnd, which yields both a Chunk (possibly) and the IndexCompact.

Synopsis

data IndexCompactAcc s = IndexCompactAcc {
- icaPrimary :: !(STRef s (NonEmpty (MVector s Word64)))
- icaClashes :: !(STRef s (NonEmpty (MVector s Bit)))
- icaTieBreaker :: !(STRef s (Map (Unsliced SerialisedKey) PageNo))
- icaLargerThanPage :: !(STRef s (NonEmpty (MVector s Bit)))
- icaMaxChunkSize :: !Int
- icaCurrentPageNumber :: !(STRef s Int)
- icaLastMaxPrimbits :: !(STRef s (SMaybe Word64))
- icaLastMinKey :: !(STRef s (SMaybe SerialisedKey))
}
new :: Int -> ST s (IndexCompactAcc s)
newWithDefaults :: ST s (IndexCompactAcc s)
appendSingle :: forall s. (SerialisedKey, SerialisedKey) -> IndexCompactAcc s -> ST s (Maybe Chunk)
appendMulti :: forall s. (SerialisedKey, Word32) -> IndexCompactAcc s -> ST s [Chunk]
unsafeEnd :: IndexCompactAcc s -> ST s (Maybe Chunk, IndexCompact)
data SMaybe a
- = SNothing
- | SJust !a
smaybe :: b -> (a -> b) -> SMaybe a -> b
unsafeWriteRange :: Unbox a => MVector s a -> Bound Int -> Bound Int -> a -> ST s ()
vectorLowerBound :: Bound Int -> Int
mvectorUpperBound :: MVector v a => v s a -> Bound Int -> Int

Construction

data IndexCompactAcc s Source #

A mutable version of IndexCompact. See incremental construction.

Constructors

IndexCompactAcc

Fields

icaPrimary :: !(STRef s (NonEmpty (MVector s Word64)))
Accumulates pinned chunks of ciPrimary.
icaClashes :: !(STRef s (NonEmpty (MVector s Bit)))
Accumulates chunks of ciClashes.
icaTieBreaker :: !(STRef s (Map (Unsliced SerialisedKey) PageNo))
Accumulates the ciTieBreaker.
icaLargerThanPage :: !(STRef s (NonEmpty (MVector s Bit)))
Accumulates chunks of ciLargerThanPage.
icaMaxChunkSize :: !Int
Maximum size of a chunk
icaCurrentPageNumber :: !(STRef s Int)
The number of the current disk page we are constructing the index for.
icaLastMaxPrimbits :: !(STRef s (SMaybe Word64))
The primary bits of the page-maximum key that we saw last.
This should be SNothing if we haven't seen any keys/pages yet.
icaLastMinKey :: !(STRef s (SMaybe SerialisedKey))
The ful minimum key of the page that we saw last.
This should be SNothing if we haven't seen any keys/pages yet.

new :: Int -> ST s (IndexCompactAcc s) Source #

new maxcsize creates a new mutable index with a maximum chunk size of maxcsize.

PRECONDITION: maxcsize > 0

Note: after initialisation, maxcsize can no longer be changed.

newWithDefaults :: ST s (IndexCompactAcc s) Source #

For a specification of this operation, see the documentation of its type-agnostic version.

appendSingle :: forall s. (SerialisedKey, SerialisedKey) -> IndexCompactAcc s -> ST s (Maybe Chunk) Source #

For a specification of this operation, see the documentation of its type-agnostic version.

appendMulti :: forall s. (SerialisedKey, Word32) -> IndexCompactAcc s -> ST s [Chunk] Source #

For a specification of this operation, see the documentation of its type-agnostic version.

unsafeEnd :: IndexCompactAcc s -> ST s (Maybe Chunk, IndexCompact) Source #

For a specification of this operation, see the documentation of its type-agnostic version.

Utility

data SMaybe a Source #

Constructors

SNothing
SJust !a

Instances

Instances details

Show a => Show (SMaybe a) Source #
Instance details Defined in Database.LSMTree.Internal.Index.CompactAcc Methods showsPrec :: Int -> SMaybe a -> ShowS # show :: SMaybe a -> String # showList :: [SMaybe a] -> ShowS #
Eq a => Eq (SMaybe a) Source #
Instance details Defined in Database.LSMTree.Internal.Index.CompactAcc Methods (==) :: SMaybe a -> SMaybe a -> Bool # (/=) :: SMaybe a -> SMaybe a -> Bool #

smaybe :: b -> (a -> b) -> SMaybe a -> b Source #

Internal: exported for testing and benchmarking

unsafeWriteRange :: Unbox a => MVector s a -> Bound Int -> Bound Int -> a -> ST s () Source #

vectorLowerBound :: Bound Int -> Int Source #

Map a Bound to the equivalent inclusive lower bound.

mvectorUpperBound :: MVector v a => v s a -> Bound Int -> Int Source #

Map a Bound to the equivalent inclusive upper bound.