Ankur Mhatre
eaa8171966
Three replicas of one application against one PostgreSQL database, proving duplicate @Scheduled execution and then removing it with ShedLock: 24 executions where 8 were due, then 7 for 7 ticks. Also measured: @SchedulerLock without @EnableSchedulerLock does nothing and warns about nothing; spring.task.scheduling.pool.size=1 does not starve a fixedRate job but delays it and fires 35 of 40 executions in a burst; and a node whose clock is 40 seconds fast takes a live lock unless the provider uses usingDbTime().
52 lines
1.6 KiB
YAML
52 lines
1.6 KiB
YAML
# Three replicas and one database, which is the smallest deployment in which a @Scheduled method
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# misbehaves. Run `docker compose up --scale app=3` if you would rather set the replica count
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# from the command line; the three named services below exist so that each one gets a stable
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# INSTANCE_ID in the transcript.
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#
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# docker compose up --build
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# docker compose exec db psql -U app -d shedlockdemo -c \
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# "select instance_id, count(*) from job_execution group by instance_id"
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#
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# SPRING_PROFILES_ACTIVE=unlocked reproduces the duplicate executions; switch it to `locked` to
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# watch the count collapse to one per tick.
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services:
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db:
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image: postgres:17
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environment:
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POSTGRES_USER: app
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POSTGRES_DB: shedlockdemo
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POSTGRES_HOST_AUTH_METHOD: trust
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ports: ["5432:5432"]
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healthcheck:
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test: ["CMD-SHELL", "pg_isready -U app -d shedlockdemo"]
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interval: 2s
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timeout: 3s
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retries: 20
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replica-1: &replica
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build: .
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depends_on:
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db: { condition: service_healthy }
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environment:
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DB_URL: jdbc:postgresql://db:5432/shedlockdemo
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DB_USER: app
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INSTANCE_ID: replica-1
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SPRING_PROFILES_ACTIVE: ${PROFILE:-unlocked}
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replica-2:
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<<: *replica
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environment:
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DB_URL: jdbc:postgresql://db:5432/shedlockdemo
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DB_USER: app
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INSTANCE_ID: replica-2
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SPRING_PROFILES_ACTIVE: ${PROFILE:-unlocked}
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replica-3:
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<<: *replica
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environment:
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DB_URL: jdbc:postgresql://db:5432/shedlockdemo
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DB_USER: app
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INSTANCE_ID: replica-3
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SPRING_PROFILES_ACTIVE: ${PROFILE:-unlocked}
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