Enum TransparentHugepageDefrag 

#[non_exhaustive]
pub enum TransparentHugepageDefrag {
    Unspecified,
    Always,
    Defer,
    DeferWithMadvise,
    Madvise,
    Never,
    UnknownValue(UnknownValue),
}

Possible values for transparent hugepage defrag support.

Working with unknown values

This enum is defined as #[non_exhaustive] because Google Cloud may add additional enum variants at any time. Adding new variants is not considered a breaking change. Applications should write their code in anticipation of:

• New values appearing in future releases of the client library, and
• New values received dynamically, without application changes.

Please consult the Working with enums section in the user guide for some guidelines.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Unspecified

Default value. GKE will not modify the kernel configuration.

Always

It means that an application requesting THP will stall on allocation failure and directly reclaim pages and compact memory in an effort to allocate a THP immediately.

Defer

It means that an application will wake kswapd in the background to reclaim pages and wake kcompactd to compact memory so that THP is available in the near future. It’s the responsibility of khugepaged to then install the THP pages later.

DeferWithMadvise

It means that an application will enter direct reclaim and compaction like always, but only for regions that have used madvise(MADV_HUGEPAGE); all other regions will wake kswapd in the background to reclaim pages and wake kcompactd to compact memory so that THP is available in the near future.

Madvise

It means that an application will enter direct reclaim like always but only for regions that are have used madvise(MADV_HUGEPAGE). This is the default kernel configuration.

Never

It means that an application will never enter direct reclaim or compaction.

UnknownValue(UnknownValue)

If set, the enum was initialized with an unknown value.

Applications can examine the value using TransparentHugepageDefrag::value or TransparentHugepageDefrag::name.

Implementations

impl TransparentHugepageDefrag

pub fn value(&self) -> Option<i32>

Gets the enum value.

Returns None if the enum contains an unknown value deserialized from the string representation of enums.

pub fn name(&self) -> Option<&str>

Gets the enum value as a string.

Returns None if the enum contains an unknown value deserialized from the integer representation of enums.

Trait Implementations

impl Clone for TransparentHugepageDefrag

fn clone(&self) -> TransparentHugepageDefrag

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for TransparentHugepageDefrag

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for TransparentHugepageDefrag

fn default() -> Self

Returns the “default value” for a type.

impl<'de> Deserialize<'de> for TransparentHugepageDefrag

fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>

where D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Display for TransparentHugepageDefrag

fn fmt(&self, f: &mut Formatter<'_>) -> Result<(), Error>

Formats the value using the given formatter.

impl From<&str> for TransparentHugepageDefrag

fn from(value: &str) -> Self

Converts to this type from the input type.

impl From<i32> for TransparentHugepageDefrag

fn from(value: i32) -> Self

Converts to this type from the input type.

impl PartialEq for TransparentHugepageDefrag

fn eq(&self, other: &TransparentHugepageDefrag) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Serialize for TransparentHugepageDefrag

fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>

where S: Serializer,

Serialize this value into the given Serde serializer.

impl StructuralPartialEq for TransparentHugepageDefrag