Documentation
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Index ¶
- func AddCountsRoute(lggr logr.Logger, mux *http.ServeMux, q CountReader)
- type Count
- type CountReader
- type Counter
- type Counts
- type FakeCountReader
- type FakeCounter
- func (f *FakeCounter) Current() (*Counts, error)
- func (f *FakeCounter) Decrease(host string, i int) error
- func (f *FakeCounter) EnsureKey(host string, _, _ time.Duration)
- func (f *FakeCounter) Increase(host string, i int) error
- func (f *FakeCounter) RemoveKey(host string) bool
- func (f *FakeCounter) UpdateBuckets(_ string, _, _ time.Duration)
- type HostAndCount
- type Memory
- func (r *Memory) Current() (*Counts, error)
- func (r *Memory) Decrease(host string, delta int) error
- func (r *Memory) EnsureKey(host string, window, granularity time.Duration)
- func (r *Memory) Increase(host string, delta int) error
- func (r *Memory) RemoveKey(host string) bool
- func (r *Memory) UpdateBuckets(host string, window, granularity time.Duration)
- type RequestsBuckets
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func AddCountsRoute ¶
func AddCountsRoute(lggr logr.Logger, mux *http.ServeMux, q CountReader)
Types ¶
type CountReader ¶
type CountReader interface {
// Current returns the current count of pending requests
// for the given hostname
Current() (*Counts, error)
}
CountReader represents the size of a virtual HTTP queue, possibly distributed across multiple HTTP server processes. It only can access the current size of the queue, not any other information about requests.
It is concurrency safe.
type Counter ¶
type Counter interface {
CountReader
// Increase increases the queue size by delta for the given host.
Increase(host string, delta int) error
// Decrease decreases the queue size by delta for the given host.
Decrease(host string, delta int) error
// EnsureKey ensures that host is represented in this counter.
EnsureKey(host string, window, granularity time.Duration)
// UpdateBuckets update request backets if there are changes
UpdateBuckets(host string, window, granularity time.Duration)
// RemoveKey tries to remove the given host and its
// associated counts from the queue. returns true if it existed,
// false otherwise.
RemoveKey(host string) bool
}
QueueCounter represents a virtual HTTP queue, possibly distributed across multiple HTTP server processes. It can only increase or decrease the size of the queue or read the current size of the queue, but not read or modify any other information about it.
Both the mutation and read functionality is concurrency safe, but the read functionality is point-in-time only
type Counts ¶
Count is a snapshot of the HTTP pending request (Concurrency) count and RPS for each host. This is a json.Marshaler, json.Unmarshaler, and fmt.Stringer implementation.
Use NewQueueCounts to create a new one of these.
func GetCounts ¶
GetQueueCounts issues an RPC call to get the queue counts from the given hostAndPort. Note that the hostAndPort should not end with a "/" and shouldn't include a path.
func (*Counts) MarshalJSON ¶
MarshalJSON implements json.Marshaler
func (*Counts) UnmarshalJSON ¶
UnmarshalJSON implements json.Unmarshaler
type FakeCountReader ¶
type FakeCountReader struct {
// contains filtered or unexported fields
}
func (*FakeCountReader) Current ¶
func (f *FakeCountReader) Current() (*Counts, error)
type FakeCounter ¶
type FakeCounter struct {
RetMap map[string]Count
ResizedCh chan HostAndCount
ResizeTimeout time.Duration
// contains filtered or unexported fields
}
func NewFakeCounter ¶
func NewFakeCounter() *FakeCounter
func (*FakeCounter) Current ¶
func (f *FakeCounter) Current() (*Counts, error)
func (*FakeCounter) Decrease ¶ added in v0.8.0
func (f *FakeCounter) Decrease(host string, i int) error
func (*FakeCounter) EnsureKey ¶ added in v0.8.0
func (f *FakeCounter) EnsureKey(host string, _, _ time.Duration)
func (*FakeCounter) Increase ¶ added in v0.8.0
func (f *FakeCounter) Increase(host string, i int) error
func (*FakeCounter) RemoveKey ¶ added in v0.8.0
func (f *FakeCounter) RemoveKey(host string) bool
func (*FakeCounter) UpdateBuckets ¶ added in v0.8.0
func (f *FakeCounter) UpdateBuckets(_ string, _, _ time.Duration)
type HostAndCount ¶
type Memory ¶
type Memory struct {
// contains filtered or unexported fields
}
Memory is a Counter implementation that holds the HTTP queue in memory only. Always use NewMemory to create one of these.
type RequestsBuckets ¶ added in v0.8.0
type RequestsBuckets struct {
// contains filtered or unexported fields
}
RequestsBuckets keeps buckets that have been collected at a certain time.
func NewRequestsBuckets ¶ added in v0.8.0
func NewRequestsBuckets(window, granularity time.Duration) *RequestsBuckets
NewRequestsBuckets generates a new RequestsBuckets with the given granularity.
func (*RequestsBuckets) IsEmpty ¶ added in v0.8.0
func (t *RequestsBuckets) IsEmpty(now time.Time) bool
IsEmpty returns true if no data has been recorded for the `window` period.
func (*RequestsBuckets) Record ¶ added in v0.8.0
func (t *RequestsBuckets) Record(now time.Time, value int)
Record adds a value with an associated time to the correct bucket. If this record would introduce a gap in the data, any intervening times between the last write and this one will be recorded as zero. If an entire window length has expired without data, the firstWrite time is reset, meaning the WindowAverage will be of a partial window until enough data is received to fill it again.
func (*RequestsBuckets) WindowAverage ¶ added in v0.8.0
func (t *RequestsBuckets) WindowAverage(now time.Time) float64
WindowAverage returns the average bucket value over the window.
If the first write was less than the window length ago, an average is returned over the partial window. For example, if firstWrite was 6 seconds ago, the average will be over these 6 seconds worth of buckets, even if the window is 60s. If a window passes with no data being received, the first write time is reset so this behaviour takes effect again.
Similarly, if we have not received recent data, the average is based on a partial window. For example, if the window is 60 seconds but we last received data 10 seconds ago, the window average will be the average over the first 50 seconds.
In other cases, for example if there are gaps in the data shorter than the window length, the missing data is assumed to be 0 and the average is over the whole window length inclusive of the missing data.
Source Files