mincore

Documentation

Index

• Constants
• func Mincore(data []byte) ([]byte, error)
• type Limiter
  • func NewLimiter(underlying *rate.Limiter, data []byte) *Limiter
  • func (l *Limiter) IsInCore(ptr uintptr) bool
  • func (l *Limiter) Update() error
  • func (l *Limiter) WaitPointer(ctx context.Context, ptr unsafe.Pointer) error
  • func (l *Limiter) WaitRange(ctx context.Context, b []byte) error

Constants

const (
	DefaultUpdateInterval = 10 * time.Second
)

Limiter defaults.

Functions

func Mincore

func Mincore(data []byte) ([]byte, error)

Mincore is a wrapper function for mincore(2).

Types

type Limiter

type Limiter struct {

	// Frequency of updates of the in-core vector.
	// Updates are performed lazily so this is the maximum frequency.
	UpdateInterval time.Duration

	// OS mincore() function.
	Mincore func(data []byte) ([]byte, error)
	// contains filtered or unexported fields
}

Limiter represents a token bucket rate limiter based on

func NewLimiter

func NewLimiter(underlying *rate.Limiter, data []byte) *Limiter

NewLimiter returns a new instance of Limiter associated with an mmap. The underlying limiter can be shared to limit faults across the entire process.

func (*Limiter) IsInCore

func (l *Limiter) IsInCore(ptr uintptr) bool

IsInCore returns true if the address is resident in memory or if the address is outside the range of the data the limiter is tracking.

func (*Limiter) Update

func (l *Limiter) Update() error

Update updates the vector of in-core pages. Automatically updated when calling Wait().

func (*Limiter) WaitPointer

func (l *Limiter) WaitPointer(ctx context.Context, ptr unsafe.Pointer) error

WaitPointer checks if ptr would cause a page fault and, if so, rate limits its access. Once a page access is limited, it's updated to be considered memory resident.

func (*Limiter) WaitRange

func (l *Limiter) WaitRange(ctx context.Context, b []byte) error

WaitRange checks all pages in b for page faults and, if so, rate limits their access. Once a page access is limited, it's updated to be considered memory resident.