GHC.RTS.Flags

Accessors to GHC RTS flags. Descriptions of flags can be seen in GHC User's Guide, or by running RTS help message using +RTS --help.

Since: 4.8.0.0

Documentation

type RtsTime = Word64

Time is defined as a StgWord64 in stg/Types.h

Since: 4.8.2.0

type RtsNat = Word32

nat defined in rts/Types.h

Since: 4.8.2.0

data RTSFlags

Parameters of the runtime system

Since: 4.8.0.0

Constructors

RTSFlags

Fields

• gcFlags :: GCFlags
• concurrentFlags :: ConcFlags
• miscFlags :: MiscFlags
• debugFlags :: DebugFlags
• costCentreFlags :: CCFlags
• profilingFlags :: ProfFlags
• traceFlags :: TraceFlags
• tickyFlags :: TickyFlags

Instances

Show RTSFlags

Methods

showsPrec :: Int -> RTSFlags -> ShowS

show :: RTSFlags -> String

showList :: [RTSFlags] -> ShowS

data GiveGCStats

Should we produce a summary of the garbage collector statistics after the program has exited?

Since: 4.8.2.0

Constructors

NoGCStats

CollectGCStats

OneLineGCStats

SummaryGCStats

VerboseGCStats

Instances

Enum GiveGCStats

Methods

succ :: GiveGCStats -> GiveGCStats

pred :: GiveGCStats -> GiveGCStats

toEnum :: Int -> GiveGCStats

fromEnum :: GiveGCStats -> Int

enumFrom :: GiveGCStats -> [GiveGCStats]

enumFromThen :: GiveGCStats -> GiveGCStats -> [GiveGCStats]

enumFromTo :: GiveGCStats -> GiveGCStats -> [GiveGCStats]

enumFromThenTo :: GiveGCStats -> GiveGCStats -> GiveGCStats -> [GiveGCStats]

Show GiveGCStats

Methods

showsPrec :: Int -> GiveGCStats -> ShowS

show :: GiveGCStats -> String

showList :: [GiveGCStats] -> ShowS

data GCFlags

Parameters of the garbage collector.

Since: 4.8.0.0

Constructors

GCFlags

Fields

• statsFile :: Maybe FilePath
• giveStats :: GiveGCStats
• maxStkSize :: RtsNat
• initialStkSize :: RtsNat
• stkChunkSize :: RtsNat
• stkChunkBufferSize :: RtsNat
• maxHeapSize :: RtsNat
• minAllocAreaSize :: RtsNat
• minOldGenSize :: RtsNat
• heapSizeSuggestion :: RtsNat
• heapSizeSuggestionAuto :: Bool
• oldGenFactor :: Double
• pcFreeHeap :: Double
• generations :: RtsNat
• steps :: RtsNat
• squeezeUpdFrames :: Bool
• compact :: Bool

  True = "compact all the time"

• compactThreshold :: Double
• sweep :: Bool

  use "mostly mark-sweep" instead of copying for the oldest generation

• ringBell :: Bool
• frontpanel :: Bool
• idleGCDelayTime :: RtsTime
• doIdleGC :: Bool
• heapBase :: Word

  address to ask the OS for memory

• allocLimitGrace :: Word

Instances

Show GCFlags

Methods

showsPrec :: Int -> GCFlags -> ShowS

show :: GCFlags -> String

showList :: [GCFlags] -> ShowS

data ConcFlags

Parameters concerning context switching

Since: 4.8.0.0

Constructors

ConcFlags

Fields

• ctxtSwitchTime :: RtsTime
• ctxtSwitchTicks :: Int

Instances

Show ConcFlags

Methods

showsPrec :: Int -> ConcFlags -> ShowS

show :: ConcFlags -> String

showList :: [ConcFlags] -> ShowS

data MiscFlags

Miscellaneous parameters

Since: 4.8.0.0

Constructors

MiscFlags

Fields

• tickInterval :: RtsTime
• installSignalHandlers :: Bool
• machineReadable :: Bool
• linkerMemBase :: Word

  address to ask the OS for memory for the linker, 0 ==> off

Instances

Show MiscFlags

Methods

showsPrec :: Int -> MiscFlags -> ShowS

show :: MiscFlags -> String

showList :: [MiscFlags] -> ShowS

data DebugFlags

Flags to control debugging output & extra checking in various subsystems.

Since: 4.8.0.0

Constructors

DebugFlags

Fields

• scheduler :: Bool

  s

• interpreter :: Bool

  i

• weak :: Bool

  w

• gccafs :: Bool

  G

• gc :: Bool

  g

• block_alloc :: Bool

  b

• sanity :: Bool

  S

• stable :: Bool

  t

• prof :: Bool

  p

• linker :: Bool

  l the object linker

• apply :: Bool

  a

• stm :: Bool

  m

• squeeze :: Bool

  z stack squeezing & lazy blackholing

• hpc :: Bool

  c coverage

• sparks :: Bool

  r

Instances

Show DebugFlags

Methods

showsPrec :: Int -> DebugFlags -> ShowS

show :: DebugFlags -> String

showList :: [DebugFlags] -> ShowS

data DoCostCentres

Should the RTS produce a cost-center summary?

Since: 4.8.2.0

Constructors

CostCentresNone

CostCentresSummary

CostCentresVerbose

CostCentresAll

CostCentresXML

Instances

Enum DoCostCentres

Methods

succ :: DoCostCentres -> DoCostCentres

pred :: DoCostCentres -> DoCostCentres

toEnum :: Int -> DoCostCentres

fromEnum :: DoCostCentres -> Int

enumFrom :: DoCostCentres -> [DoCostCentres]

enumFromThen :: DoCostCentres -> DoCostCentres -> [DoCostCentres]

enumFromTo :: DoCostCentres -> DoCostCentres -> [DoCostCentres]

enumFromThenTo :: DoCostCentres -> DoCostCentres -> DoCostCentres -> [DoCostCentres]

Show DoCostCentres

Methods

showsPrec :: Int -> DoCostCentres -> ShowS

show :: DoCostCentres -> String

showList :: [DoCostCentres] -> ShowS

data CCFlags

Parameters pertaining to the cost-center profiler.

Since: 4.8.0.0

Constructors

CCFlags

Fields

• doCostCentres :: DoCostCentres
• profilerTicks :: Int
• msecsPerTick :: Int

Instances

Show CCFlags

Methods

showsPrec :: Int -> CCFlags -> ShowS

show :: CCFlags -> String

showList :: [CCFlags] -> ShowS

data DoHeapProfile

What sort of heap profile are we collecting?

Since: 4.8.2.0

Constructors

NoHeapProfiling

HeapByCCS

HeapByMod

HeapByDescr

HeapByType

HeapByRetainer

HeapByLDV

HeapByClosureType

Instances

Enum DoHeapProfile

Methods

succ :: DoHeapProfile -> DoHeapProfile

pred :: DoHeapProfile -> DoHeapProfile

toEnum :: Int -> DoHeapProfile

fromEnum :: DoHeapProfile -> Int

enumFrom :: DoHeapProfile -> [DoHeapProfile]

enumFromThen :: DoHeapProfile -> DoHeapProfile -> [DoHeapProfile]

enumFromTo :: DoHeapProfile -> DoHeapProfile -> [DoHeapProfile]

enumFromThenTo :: DoHeapProfile -> DoHeapProfile -> DoHeapProfile -> [DoHeapProfile]

Show DoHeapProfile

Methods

showsPrec :: Int -> DoHeapProfile -> ShowS

show :: DoHeapProfile -> String

showList :: [DoHeapProfile] -> ShowS

data ProfFlags

Parameters of the cost-center profiler

Since: 4.8.0.0

Constructors

ProfFlags

Fields

• doHeapProfile :: DoHeapProfile
• heapProfileInterval :: RtsTime

  time between samples

• heapProfileIntervalTicks :: Word

  ticks between samples (derived)

• includeTSOs :: Bool
• showCCSOnException :: Bool
• maxRetainerSetSize :: Word
• ccsLength :: Word
• modSelector :: Maybe String
• descrSelector :: Maybe String
• typeSelector :: Maybe String
• ccSelector :: Maybe String
• ccsSelector :: Maybe String
• retainerSelector :: Maybe String
• bioSelector :: Maybe String

Instances

Show ProfFlags

Methods

showsPrec :: Int -> ProfFlags -> ShowS

show :: ProfFlags -> String

showList :: [ProfFlags] -> ShowS

data DoTrace

Is event tracing enabled?

Since: 4.8.2.0

Constructors

TraceNone

no tracing

TraceEventLog

send tracing events to the event log

TraceStderr

send tracing events to stderr

Instances

Enum DoTrace

Methods

succ :: DoTrace -> DoTrace

pred :: DoTrace -> DoTrace

toEnum :: Int -> DoTrace

fromEnum :: DoTrace -> Int

enumFrom :: DoTrace -> [DoTrace]

enumFromThen :: DoTrace -> DoTrace -> [DoTrace]

enumFromTo :: DoTrace -> DoTrace -> [DoTrace]

enumFromThenTo :: DoTrace -> DoTrace -> DoTrace -> [DoTrace]

Show DoTrace

Methods

showsPrec :: Int -> DoTrace -> ShowS

show :: DoTrace -> String

showList :: [DoTrace] -> ShowS

data TraceFlags

Parameters pertaining to event tracing

Since: 4.8.0.0

Constructors

TraceFlags

Fields

• tracing :: DoTrace
• timestamp :: Bool

  show timestamp in stderr output

• traceScheduler :: Bool

  trace scheduler events

• traceGc :: Bool

  trace GC events

• sparksSampled :: Bool

  trace spark events by a sampled method

• sparksFull :: Bool

  trace spark events 100% accurately

• user :: Bool

  trace user events (emitted from Haskell code)

Instances

Show TraceFlags

Methods

showsPrec :: Int -> TraceFlags -> ShowS

show :: TraceFlags -> String

showList :: [TraceFlags] -> ShowS

data TickyFlags

Parameters pertaining to ticky-ticky profiler

Since: 4.8.0.0

Constructors

TickyFlags

Fields

• showTickyStats :: Bool
• tickyFile :: Maybe FilePath

Instances

Show TickyFlags

Methods

showsPrec :: Int -> TickyFlags -> ShowS

show :: TickyFlags -> String

showList :: [TickyFlags] -> ShowS

getRTSFlags :: IO RTSFlags

getGCFlags :: IO GCFlags

getConcFlags :: IO ConcFlags

getMiscFlags :: IO MiscFlags

getDebugFlags :: IO DebugFlags

getCCFlags :: IO CCFlags

getProfFlags :: IO ProfFlags

getTraceFlags :: IO TraceFlags

getTickyFlags :: IO TickyFlags