scheduler

Documentation

Index

• func SafeReadRing(s *RingManager) ring.ReadRing
• type Config
  • func (cfg *Config) RegisterFlags(f *flag.FlagSet)
• type Limits
• type RingManager
  • func NewRingManager(managerMode RingManagerMode, cfg Config, log log.Logger, ...) (*RingManager, error)
  • func (rm *RingManager) OnRingInstanceHeartbeat(_ *ring.BasicLifecycler, _ *ring.Desc, _ *ring.InstanceDesc)
  • func (rm *RingManager) OnRingInstanceRegister(_ *ring.BasicLifecycler, ringDesc ring.Desc, instanceExists bool, _ string, ...) (ring.InstanceState, ring.Tokens)
  • func (rm *RingManager) OnRingInstanceStopping(_ *ring.BasicLifecycler)
  • func (rm *RingManager) OnRingInstanceTokens(_ *ring.BasicLifecycler, _ ring.Tokens)
  • func (rm *RingManager) ServeHTTP(w http.ResponseWriter, req *http.Request)
• type RingManagerMode
• type Scheduler
  • func NewScheduler(cfg Config, limits Limits, log log.Logger, ringManager *RingManager, ...) (*Scheduler, error)
  • func (s *Scheduler) FrontendLoop(frontend schedulerpb.SchedulerForFrontend_FrontendLoopServer) error
  • func (s *Scheduler) NotifyQuerierShutdown(_ context.Context, req *schedulerpb.NotifyQuerierShutdownRequest) (*schedulerpb.NotifyQuerierShutdownResponse, error)
  • func (s *Scheduler) QuerierLoop(querier schedulerpb.SchedulerForQuerier_QuerierLoopServer) error

Functions

func SafeReadRing

func SafeReadRing(s *RingManager) ring.ReadRing

SafeReadRing does a nil check on the Scheduler before attempting to return it's ring this is necessary as many callers of this function will only have a valid Scheduler reference if the QueryScheduler target has been specified, which is not guaranteed

Types

type Config

type Config struct {
	MaxOutstandingPerTenant int               `yaml:"max_outstanding_requests_per_tenant"`
	MaxQueueHierarchyLevels int               `yaml:"max_queue_hierarchy_levels"`
	QuerierForgetDelay      time.Duration     `yaml:"querier_forget_delay"`
	GRPCClientConfig        grpcclient.Config `yaml:"grpc_client_config" doc:"description=This configures the gRPC client used to report errors back to the query-frontend."`
	// Schedulers ring
	UseSchedulerRing bool            `yaml:"use_scheduler_ring"`
	SchedulerRing    util.RingConfig `` /* 138-byte string literal not displayed */
}

func (*Config) RegisterFlags

func (cfg *Config) RegisterFlags(f *flag.FlagSet)

type Limits

type Limits interface {
	// MaxQueriersPerUser returns max queriers to use per tenant, or 0 if shuffle sharding is disabled.
	MaxQueriersPerUser(user string) int
}

Limits needed for the Query Scheduler - interface used for decoupling.

type RingManager

type RingManager struct {
	services.Service

	RingLifecycler *ring.BasicLifecycler
	Ring           *ring.Ring
	// contains filtered or unexported fields
}

RingManager is a component instantiated before all the others and is responsible for the ring setup.

All Loki components that are involved with the Schedulers (including the Schedulers itself) will require a RingManager. However, the components that are clients of the Schedulers will run it in reader mode while the Schedulers itself will run the manager in member mode.

func NewRingManager

func NewRingManager(managerMode RingManagerMode, cfg Config, log log.Logger, registerer prometheus.Registerer) (*RingManager, error)

NewRingManager is the recommended way of instantiating a RingManager.

The other functions will assume the RingManager was instantiated through this function.

func (*RingManager) OnRingInstanceHeartbeat

func (rm *RingManager) OnRingInstanceHeartbeat(_ *ring.BasicLifecycler, _ *ring.Desc, _ *ring.InstanceDesc)

func (*RingManager) OnRingInstanceRegister

func (rm *RingManager) OnRingInstanceRegister(_ *ring.BasicLifecycler, ringDesc ring.Desc, instanceExists bool, _ string, instanceDesc ring.InstanceDesc) (ring.InstanceState, ring.Tokens)

func (*RingManager) OnRingInstanceStopping

func (rm *RingManager) OnRingInstanceStopping(_ *ring.BasicLifecycler)

func (*RingManager) OnRingInstanceTokens

func (rm *RingManager) OnRingInstanceTokens(_ *ring.BasicLifecycler, _ ring.Tokens)

func (*RingManager) ServeHTTP

func (rm *RingManager) ServeHTTP(w http.ResponseWriter, req *http.Request)

ServeHTTP serves the HTTP route /scheduler/ring.

type RingManagerMode

type RingManagerMode int

RingManagerMode defines the different modes for the RingManager to execute.

The RingManager and its modes are only relevant if the Scheduler discovery is done using ring.

const (
	// RingManagerModeReader is the RingManager mode executed by Loki components that want to discover Scheduler instances.
	// The RingManager in reader mode will have its own ring key-value store client, but it won't try to register itself in the ring.
	RingManagerModeReader RingManagerMode = iota

	// RingManagerModeMember is the RingManager mode execute by the Schedulers to register themselves in the ring.
	RingManagerModeMember
)

type Scheduler

type Scheduler struct {
	services.Service
	// contains filtered or unexported fields
}

Scheduler is responsible for queueing and dispatching queries to Queriers.

func NewScheduler

func NewScheduler(cfg Config, limits Limits, log log.Logger, ringManager *RingManager, registerer prometheus.Registerer) (*Scheduler, error)

NewScheduler creates a new Scheduler.

func (*Scheduler) FrontendLoop

func (s *Scheduler) FrontendLoop(frontend schedulerpb.SchedulerForFrontend_FrontendLoopServer) error

FrontendLoop handles connection from frontend.

func (*Scheduler) NotifyQuerierShutdown

func (s *Scheduler) NotifyQuerierShutdown(_ context.Context, req *schedulerpb.NotifyQuerierShutdownRequest) (*schedulerpb.NotifyQuerierShutdownResponse, error)

func (*Scheduler) QuerierLoop

func (s *Scheduler) QuerierLoop(querier schedulerpb.SchedulerForQuerier_QuerierLoopServer) error

QuerierLoop is started by querier to receive queries from scheduler.