Safe Haskell	None
Language	GHC2021

Ecluse.Core.Queue.Memory

Contents

Bounded in-memory production backend

Description

The STM-backed in-memory MirrorQueue: the bounded, best-effort production backend mirroring rolls over to when no ECLUSE_QUEUE__URL is set.

It honours the handle's contract (Ecluse.Core.Queue) with two departures. enqueue drops the newest job past the depth cap, and a receive is final, so nothing redelivers and no delivery carries a lease. Both are safe because the next demand re-enqueues the job.

Synopsis

data MemoryQueueConfig = MemoryQueueConfig {
- memQueueMaxDepth :: Int
- memQueuePollWaitMicros :: Int
}
defaultMemoryQueueConfig :: Int -> MemoryQueueConfig
newBoundedInMemoryQueue :: MemoryQueueConfig -> (Int -> IO ()) -> IO MirrorQueue
memoryQueueDropReportInterval :: Int

Bounded in-memory production backend

data MemoryQueueConfig Source #

The bounded in-memory backend's depth cap and idle-poll window. Build it with defaultMemoryQueueConfig for the production poll window.

Constructors

MemoryQueueConfig

Fields

memQueueMaxDepth :: Int
The maximum number of jobs the queue holds. The config layer enforces a positive cap. An enqueue past it drops the newest job, a safe loss because the next demand re-enqueues.
memQueuePollWaitMicros :: Int
The idle long-poll window in microseconds: how long a receive waits for a job before returning []. The bound keeps the worker's liveness heartbeat advancing on an idle queue.

Instances

Instances details

Show MemoryQueueConfig Source #
Instance details Defined in Ecluse.Core.Queue.Memory Methods showsPrec :: Int -> MemoryQueueConfig -> ShowS # show :: MemoryQueueConfig -> String # showList :: [MemoryQueueConfig] -> ShowS #
Eq MemoryQueueConfig Source #
Instance details Defined in Ecluse.Core.Queue.Memory Methods (==) :: MemoryQueueConfig -> MemoryQueueConfig -> Bool # (/=) :: MemoryQueueConfig -> MemoryQueueConfig -> Bool #

defaultMemoryQueueConfig :: Int -> MemoryQueueConfig Source #

A MemoryQueueConfig at the production 20s idle-poll window, which sits under workerHeartbeatStaleAfter so an idle poll cannot stall /livez.

newBoundedInMemoryQueue Source #

Arguments

:: MemoryQueueConfig	The depth cap and the idle-poll window.
-> (Int -> IO ())	Invoked on each report-worthy cap-overflow drop with the running total, for the log.
-> IO MirrorQueue

Build the bounded, best-effort in-memory MirrorQueue. A cold-cache npm ci enqueues thousands of jobs at once, so enqueue sheds past memQueueMaxDepth rather than throwing.

memoryQueueDropReportInterval :: Int Source #

How many cap-overflow drops the bounded in-memory backend absorbs between warning reports. It reports the first drop, then every multiple of this, so a sustained flood cannot spam.