Copyright | (c) The University of Glasgow 2001 |
---|---|
License | BSD-style (see the file libraries/base/LICENSE) |
Maintainer | [email protected] |
Stability | provisional |
Portability | portable |
Safe Haskell | Trustworthy |
Language | Haskell2010 |
Memory-related system things.
Triggers an immediate major garbage collection.
performMajorGC :: IO () Source
Triggers an immediate major garbage collection.
Since: 4.7.0.0
performMinorGC :: IO () Source
Triggers an immediate minor garbage collection.
Since: 4.7.0.0
setAllocationCounter :: Int64 -> IO () Source
Every thread has an allocation counter that tracks how much memory has been allocated by the thread. The counter is initialized to zero, and setAllocationCounter
sets the current value. The allocation counter counts *down*, so in the absence of a call to setAllocationCounter
its value is the negation of the number of bytes of memory allocated by the thread.
There are two things that you can do with this counter:
getAllocationCounter
.enableAllocationLimit
.Allocation accounting is accurate only to about 4Kbytes.
Since: 4.8.0.0
getAllocationCounter :: IO Int64 Source
Return the current value of the allocation counter for the current thread.
Since: 4.8.0.0
enableAllocationLimit :: IO () Source
Enables the allocation counter to be treated as a limit for the current thread. When the allocation limit is enabled, if the allocation counter counts down below zero, the thread will be sent the AllocationLimitExceeded
asynchronous exception. When this happens, the counter is reinitialised (by default to 100K, but tunable with the +RTS -xq
option) so that it can handle the exception and perform any necessary clean up. If it exhausts this additional allowance, another AllocationLimitExceeded
exception is sent, and so forth. Like other asynchronous exceptions, the AllocationLimitExceeded
exception is deferred while the thread is inside mask
or an exception handler in catch
.
Note that memory allocation is unrelated to live memory, also known as heap residency. A thread can allocate a large amount of memory and retain anything between none and all of it. It is better to think of the allocation limit as a limit on CPU time, rather than a limit on memory.
Compared to using timeouts, allocation limits don't count time spent blocked or in foreign calls.
Since: 4.8.0.0
disableAllocationLimit :: IO () Source
Disable allocation limit processing for the current thread.
Since: 4.8.0.0
© The University of Glasgow and others
Licensed under a BSD-style license (see top of the page).
https://downloads.haskell.org/~ghc/8.2.1/docs/html/libraries/base-4.10.0.0/System-Mem.html