Struct gio::MemoryMonitor [−][src]
pub struct MemoryMonitor(_);
Expand description
MemoryMonitor
will monitor system memory and suggest to the application
when to free memory so as to leave more room for other applications.
It is implemented on Linux using the Low Memory Monitor
(API documentation).
There is also an implementation for use inside Flatpak sandboxes.
Possible actions to take when the signal is received are:
- Free caches
- Save files that haven’t been looked at in a while to disk, ready to be reopened when needed
- Run a garbage collection cycle
- Try and compress fragmented allocations
- Exit on idle if the process has no reason to stay around
- Call
malloc_trim(3)
to return cached heap pages to the kernel (if supported by your libc)
Note that some actions may not always improve system performance, and so
should be profiled for your application. malloc_trim()
, for example, may
make future heap allocations slower (due to releasing cached heap pages back
to the kernel).
See MemoryMonitorWarningLevel
for details on the various warning levels.
⚠️ The following code is in C ⚠️
static void
warning_cb (GMemoryMonitor *m, GMemoryMonitorWarningLevel level)
{
g_debug ("Warning level: %d", level);
if (warning_level > G_MEMORY_MONITOR_WARNING_LEVEL_LOW)
drop_caches ();
}
static GMemoryMonitor *
monitor_low_memory (void)
{
GMemoryMonitor *m;
m = g_memory_monitor_dup_default ();
g_signal_connect (G_OBJECT (m), "low-memory-warning",
G_CALLBACK (warning_cb), NULL);
return m;
}
Don’t forget to disconnect the signal::MemoryMonitor::low-memory-warning
signal, and unref the MemoryMonitor
itself when exiting.
Implements
Implementations
This is supported on crate feature v2_64
only.
v2_64
only.Gets a reference to the default MemoryMonitor
for the system.
Returns
a new reference to the default MemoryMonitor
Trait Implementations
This method returns an ordering between self
and other
values if one exists. Read more
This method tests less than (for self
and other
) and is used by the <
operator. Read more
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
This method tests greater than (for self
and other
) and is used by the >
operator. Read more
Returns the type identifier of Self
.
Auto Trait Implementations
impl RefUnwindSafe for MemoryMonitor
impl !Send for MemoryMonitor
impl !Sync for MemoryMonitor
impl Unpin for MemoryMonitor
impl UnwindSafe for MemoryMonitor
Blanket Implementations
Mutably borrows from an owned value. Read more
Upcasts an object to a superclass or interface T
. Read more
Upcasts an object to a reference of its superclass or interface T
. Read more
Tries to downcast to a subclass or interface implementor T
. Read more
Tries to downcast to a reference of its subclass or interface implementor T
. Read more
Tries to cast to an object of type T
. This handles upcasting, downcasting
and casting between interface and interface implementors. All checks are performed at
runtime, while downcast
and upcast
will do many checks at compile-time already. Read more
Tries to cast to reference to an object of type T
. This handles upcasting, downcasting
and casting between interface and interface implementors. All checks are performed at
runtime, while downcast
and upcast
will do many checks at compile-time already. Read more
Casts to T
unconditionally. Read more
Casts to &T
unconditionally. Read more
Returns true
if the object is an instance of (can be cast to) T
.
pub fn set_properties_from_value(
&self,
property_values: &[(&str, Value)]
) -> Result<(), BoolError>
pub fn set_property<'a, N, V>(
&self,
property_name: N,
value: V
) -> Result<(), BoolError> where
V: ToValue,
N: Into<&'a str>,
pub fn set_property_from_value<'a, N>(
&self,
property_name: N,
value: &Value
) -> Result<(), BoolError> where
N: Into<&'a str>,
Safety Read more
Safety Read more
Safety Read more
Safety Read more
pub fn connect_notify<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec) + Send + Sync,
pub fn connect_notify_local<F>(
&self,
name: Option<&str>,
f: F
) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec),
pub unsafe fn connect_notify_unsafe<F>(
&self,
name: Option<&str>,
f: F
) -> SignalHandlerId where
F: Fn(&T, &ParamSpec),
pub fn has_property<'a, N>(&self, property_name: N, type_: Option<Type>) -> bool where
N: Into<&'a str>,
pub fn find_property<'a, N>(&self, property_name: N) -> Option<ParamSpec> where
N: Into<&'a str>,
pub fn connect<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value> + Send + Sync + 'static,
N: Into<&'a str>,
Same as connect
but takes a SignalId
instead of a signal name.
pub fn connect_local<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value> + 'static,
N: Into<&'a str>,
Same as connect_local
but takes a SignalId
instead of a signal name.
pub unsafe fn connect_unsafe<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value>,
N: Into<&'a str>,
Same as connect_unsafe
but takes a SignalId
instead of a signal name.
Emit signal by signal id.
Emit signal with details by signal id.
Emit signal by it’s name.
pub fn bind_property<'a, O, N, M>(
&'a self,
source_property: N,
target: &'a O,
target_property: M
) -> BindingBuilder<'a> where
O: ObjectType,
N: Into<&'a str>,
M: Into<&'a str>,
Same as emit
but takes Value
for the arguments.
Same as emit_by_name
but takes Value
for the arguments.
Returns a SendValue
clone of self
.
impl<'a, T, C> FromValueOptional<'a> for T where
C: ValueTypeChecker<Error = ValueTypeMismatchOrNoneError>,
T: FromValue<'a, Checker = C>,