GI.GLib.Structs.ThreadPool

The ThreadPool struct represents a thread pool. It has three public read-only members, but the underlying struct is bigger, so you must not copy this struct.

Exported types

newtype ThreadPool

Memory-managed wrapper type.

Constructors

ThreadPool (ManagedPtr ThreadPool)

Instances

Eq ThreadPool

Defined in GI.GLib.Structs.ThreadPool

Methods

(==) :: ThreadPool -> ThreadPool -> Bool

(/=) :: ThreadPool -> ThreadPool -> Bool

WrappedPtr ThreadPool

Defined in GI.GLib.Structs.ThreadPool

Methods

wrappedPtrCalloc :: IO (Ptr ThreadPool)

wrappedPtrCopy :: ThreadPool -> IO ThreadPool

wrappedPtrFree :: Maybe (GDestroyNotify ThreadPool)

tag ~ 'AttrSet => Constructible ThreadPool tag

Defined in GI.GLib.Structs.ThreadPool

Methods

new :: MonadIO m => (ManagedPtr ThreadPool -> ThreadPool) -> [AttrOp ThreadPool tag] -> m ThreadPool

newZeroThreadPool :: MonadIO m => m ThreadPool

Construct a ThreadPool struct initialized to zero.

noThreadPool :: Maybe ThreadPool

A convenience alias for Nothing :: Maybe ThreadPool.

Methods

Overloaded methods

free

threadPoolFree

Arguments

:: (HasCallStack, MonadIO m)

=> ThreadPool

pool: a ThreadPool

-> Bool

immediate: should pool shut down immediately?

-> Bool

wait_: should the function wait for all tasks to be finished?

-> m ()

Frees all resources allocated for pool.

If immediate is True, no new task is processed for pool. Otherwise pool is not freed before the last task is processed. Note however, that no thread of this pool is interrupted while processing a task. Instead at least all still running threads can finish their tasks before the pool is freed.

If wait_ is True, the functions does not return before all tasks to be processed (dependent on immediate, whether all or only the currently running) are ready. Otherwise the function returns immediately.

After calling this function pool must not be used anymore.

getMaxIdleTime

threadPoolGetMaxIdleTime

Arguments

:: (HasCallStack, MonadIO m)

=> m Word32

Returns: the maximum interval (milliseconds) to wait for new tasks in the thread pool before stopping the thread

This function will return the maximum interval that a thread will wait in the thread pool for new tasks before being stopped.

If this function returns 0, threads waiting in the thread pool for new work are not stopped.

Since: 2.10

getMaxThreads

threadPoolGetMaxThreads

Arguments

:: (HasCallStack, MonadIO m)

=> ThreadPool

pool: a ThreadPool

-> m Int32

Returns: the maximal number of threads

Returns the maximal number of threads for pool.

getMaxUnusedThreads

threadPoolGetMaxUnusedThreads

Arguments

:: (HasCallStack, MonadIO m)

=> m Int32

Returns: the maximal number of unused threads

Returns the maximal allowed number of unused threads.

getNumThreads

threadPoolGetNumThreads

Arguments

:: (HasCallStack, MonadIO m)

=> ThreadPool

pool: a ThreadPool

-> m Word32

Returns: the number of threads currently running

Returns the number of threads currently running in pool.

getNumUnusedThreads

threadPoolGetNumUnusedThreads

Arguments

:: (HasCallStack, MonadIO m)

=> m Word32

Returns: the number of currently unused threads

Returns the number of currently unused threads.

moveToFront

threadPoolMoveToFront

Arguments

:: (HasCallStack, MonadIO m)

=> ThreadPool

pool: a ThreadPool

-> Ptr ()

data: an unprocessed item in the pool

-> m Bool

Returns: True if the item was found and moved

Moves the item to the front of the queue of unprocessed items, so that it will be processed next.

Since: 2.46

push

threadPoolPush

Arguments

:: (HasCallStack, MonadIO m)

=> ThreadPool

pool: a ThreadPool

-> Ptr ()

data: a new task for pool

-> m ()

(Can throw GError)

Inserts data into the list of tasks to be executed by pool.

When the number of currently running threads is lower than the maximal allowed number of threads, a new thread is started (or reused) with the properties given to g_thread_pool_new(). Otherwise, data stays in the queue until a thread in this pool finishes its previous task and processes data.

error can be Nothing to ignore errors, or non-Nothing to report errors. An error can only occur when a new thread couldn't be created. In that case data is simply appended to the queue of work to do.

Before version 2.32, this function did not return a success status.

setMaxIdleTime

threadPoolSetMaxIdleTime

Arguments

:: (HasCallStack, MonadIO m)

=> Word32

interval: the maximum interval (in milliseconds) a thread can be idle

-> m ()

This function will set the maximum interval that a thread waiting in the pool for new tasks can be idle for before being stopped. This function is similar to calling threadPoolStopUnusedThreads on a regular timeout, except this is done on a per thread basis.

By setting interval to 0, idle threads will not be stopped.

The default value is 15000 (15 seconds).

Since: 2.10

setMaxThreads

threadPoolSetMaxThreads

Arguments

:: (HasCallStack, MonadIO m)

=> ThreadPool

pool: a ThreadPool

-> Int32

maxThreads: a new maximal number of threads for pool, or -1 for unlimited

-> m ()

(Can throw GError)

Sets the maximal allowed number of threads for pool. A value of -1 means that the maximal number of threads is unlimited. If pool is an exclusive thread pool, setting the maximal number of threads to -1 is not allowed.

Setting maxThreads to 0 means stopping all work for pool. It is effectively frozen until maxThreads is set to a non-zero value again.

A thread is never terminated while calling func, as supplied by g_thread_pool_new(). Instead the maximal number of threads only has effect for the allocation of new threads in threadPoolPush. A new thread is allocated, whenever the number of currently running threads in pool is smaller than the maximal number.

error can be Nothing to ignore errors, or non-Nothing to report errors. An error can only occur when a new thread couldn't be created.

Before version 2.32, this function did not return a success status.

setMaxUnusedThreads

threadPoolSetMaxUnusedThreads

Arguments

:: (HasCallStack, MonadIO m)

=> Int32

maxThreads: maximal number of unused threads

-> m ()

Sets the maximal number of unused threads to maxThreads. If maxThreads is -1, no limit is imposed on the number of unused threads.

The default value is 2.

stopUnusedThreads

threadPoolStopUnusedThreads :: (HasCallStack, MonadIO m) => m ()

Stops all currently unused threads. This does not change the maximal number of unused threads. This function can be used to regularly stop all unused threads e.g. from g_timeout_add().

unprocessed

threadPoolUnprocessed

Arguments

:: (HasCallStack, MonadIO m)

=> ThreadPool

pool: a ThreadPool

-> m Word32

Returns: the number of unprocessed tasks

Returns the number of tasks still unprocessed in pool.

Properties

exclusive

are all threads exclusive to this pool

getThreadPoolExclusive :: MonadIO m => ThreadPool -> m Bool

Get the value of the “exclusive” field. When overloading is enabled, this is equivalent to

get threadPool #exclusive

setThreadPoolExclusive :: MonadIO m => ThreadPool -> Bool -> m ()

Set the value of the “exclusive” field. When overloading is enabled, this is equivalent to

set threadPool [ #exclusive := value ]

func

the function to execute in the threads of this pool

clearThreadPoolFunc :: MonadIO m => ThreadPool -> m ()

Set the value of the “func” field to Nothing. When overloading is enabled, this is equivalent to

clear #func

getThreadPoolFunc :: MonadIO m => ThreadPool -> m (Maybe Func_WithClosures)

Get the value of the “func” field. When overloading is enabled, this is equivalent to

get threadPool #func

setThreadPoolFunc :: MonadIO m => ThreadPool -> FunPtr C_Func -> m ()

Set the value of the “func” field. When overloading is enabled, this is equivalent to

set threadPool [ #func := value ]

userData

the user data for the threads of this pool

clearThreadPoolUserData :: MonadIO m => ThreadPool -> m ()

Set the value of the “user_data” field to Nothing. When overloading is enabled, this is equivalent to

clear #userData

getThreadPoolUserData :: MonadIO m => ThreadPool -> m (Ptr ())

Get the value of the “user_data” field. When overloading is enabled, this is equivalent to

get threadPool #userData

setThreadPoolUserData :: MonadIO m => ThreadPool -> Ptr () -> m ()

Set the value of the “user_data” field. When overloading is enabled, this is equivalent to

set threadPool [ #userData := value ]