GHC.Debug.Fragmentation

Functions for analysing memory fragmentation

Documentation

summariseBlocks :: [RawBlock] -> IO ()

Print a summary of the given raw blocks This is useful to see how many MBlocks and how many pinned blocks there are.

censusByMBlock :: [ClosurePtr] -> DebugM (Map BlockPtr CensusStats)

Perform a heap census by which MBlock each closure lives in

printMBlockCensus :: Map BlockPtr CensusStats -> IO ()

censusByBlock :: [ClosurePtr] -> DebugM (Map BlockPtr CensusStats)

Perform a census based on which block each closure resides in.

printBlockCensus :: Map BlockPtr CensusStats -> IO ()

Print out a block census

censusPinnedBlocks :: [RawBlock] -> [ClosurePtr] -> DebugM (Map BlockPtr PinnedCensusStats)

Only census the given (pinned) blocks

newtype PinnedCensusStats

Constructors

PinnedCensusStats (CensusStats, [(ClosurePtr, SizedClosure)])

Instances

Semigroup PinnedCensusStats

Defined in GHC.Debug.Fragmentation

Methods

(<>) :: PinnedCensusStats -> PinnedCensusStats -> PinnedCensusStats

sconcat :: NonEmpty PinnedCensusStats -> PinnedCensusStats

stimes :: Integral b => b -> PinnedCensusStats -> PinnedCensusStats

findBadPtrs :: Map k PinnedCensusStats -> [((Count, [ClosurePtr]), String)]

Given a pinned block census, find the ARR_WORDS objects which are in the blocks which are < 10 % utilised. The return list is sorted by how many times each distinct ARR_WORDS appears on the heap.

histogram :: Word64 -> [CensusStats] -> IO ()

Print either a MBlock or Block census as a histogram