The Citus Data Scale Out Story | PostgresOpen SV 2018 | Ozgun Erdogan, Marco Slot

Transcript

1. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   The Citus Data
   Scale Out Story
   Ozgun Erdogan & Marco Slot
   PostgresOpen SV | Sep 06, 2018 | San Francisco
   

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2. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   2
   The story
   before the
   story…
   Citus Data Co-Founders, Left to Right
   Ozgun Erdogan, Sumedh Pathak, Umur Cubukcu
   Photo credit: Willy Johnson 2017
   

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3. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   Our early
   days at
   Amazon
   spent working on
   distributed systems
   3
   

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4. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   Each service
   needs to
   elastically scale
   Scaling compute is easy
   Scaling data is hard
   NoSQL
   ?
   

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5. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   Hidden costs
   of NoSQL
   What if a
   relational
   database could
   scale out
   ?
   TRANSACTIONS
   JOINS
   DATABASE CONSTRAINTS
   Re-architect application (more code) to
   provide missing database functionality
   

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6. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   What better
   way to scale a
   relational
   database
   than to extend the
   world’s best database?
   

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7. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   7
   Citus Scales Out PostgreSQL
   COORDINATOR
   NODE
   Table metadata
   SELECT FROM table_1001
   SELECT FROM table_1003
   SELECT FROM table_1002
   SELECT FROM table_1004
   WORKER NODE 1
   Table_1001
   Table_1003
   WORKER NODE 2
   Table_1002
   Table_1004
   WORKER NODE ‘N’
   Each node PostgreSQL instance
   with Citus installed
   Replication not shown in diagram
   ●
   ●
   ●
   ●
   ●
   ●
   SELECT
   create_distributed_table(‘table’,
   ‘device_id’);
   

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8. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   Reasons to love Citus—let’s count the ways
   8
   

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9. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
   9
   Easy to scale out a Citus database cluster
   

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10. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    • Citus parallelizes query across cluster of machines.
    • Citus comes with 3 distributed executors.
    Query Parallelization
    

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11. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    • Distributed transactions could lead to distributed
    deadlocks.
    • To avoid deadlocks, we introduced a distributed
    deadlock detector.
    Distributed transactions in Citus
    

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12. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    One important
    gap remains
    

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13. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    13
    Citus Architecture
    COORDINATOR
    NODE
    Table metadata
    SELECT FROM table_1001
    SELECT FROM table_1003
    SELECT FROM table_1002
    SELECT FROM table_1004
    WORKER NODE 1
    Table_1001
    Table_1003
    WORKER NODE 2
    Table_1002
    Table_1004
    WORKER NODE ‘N’
    Each node PostgreSQL instance
    with Citus installed
    Replication not shown in diagram
    ●
    ●
    ●
    ●
    ●
    ●
    SELECT
    create_distributed_table(‘table’,
    ‘device_id’);
    

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14. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    1.High write throughput
    2.Query planning times for large deployments
    3.High Availability (HA) for each node
    What if you could talk to any node?
    

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15. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    • Citus coordinator routes queries to worker nodes.
    • For workloads that require high write throughput
    (10B+ writes per day), coordinator could become a
    bottleneck.
    High Write Throughput
    

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16. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    • The coordinator plans analytical queries for
    distributed execution.
    Query Planning in Large Deployments
    >650K ½-1
    shards seconds concurrency
    L
    

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17. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    • When coordinator fails, your cluster can become
    unavailable up to 1 minute. That’s a long time.
    • When any node can coordinate, you get higher
    availability for on a per-shard basis.
    High Availability (HA) for each shard
    

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18. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    • What if better HA were possible?
    • What if higher write throughput were possible?
    • What would such a solution’s performance look
    like?
    What if we had such a solution?
    

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19. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    0
    50,000
    100,000
    150,000
    200,000
    250,000
    4 8 12
    # nodes
    0
    20
    40
    60
    80
    100
    120
    4 8 12
    # nodes
    Transaction performance (TPS)
    Queries per hour (QPH)
    19
    Performance for prominent service today
    Transaction (OLTP) speed Analytics (OLAP) speed
    Prominent
    Postgres
    service
    Prominent
    Postgres
    service
    

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20. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    0
    50,000
    100,000
    150,000
    200,000
    250,000
    4 8 12
    Transaction (OLTP) speed
    # nodes
    0
    20
    40
    60
    80
    100
    120
    4 8 12
    # nodes
    Analytics (OLAP) speed
    Queries per hour (QPH)
    5x
    faster
    70x
    faster
    Citus
    Prominent
    Postgres
    service
    20
    Higher Performance with Citus MX
    Citus
    Prominent
    Postgres
    service
    Transaction performance (TPS)
    

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21. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    Introducing
    Citus MX
    

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22. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    Thank You.
    ozgun@citusdata.com
    marco@citusdata.com
    @citusdata
    Ozgun Erdogan, CTO & Co-Founder
    Marco Slot, Principal Engineer
    www.citusdata.com
    

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23. PostgresOpen SV 2018 Keynote | Ozgun Erdogan & Marco Slot | Citus Data
    What if super
    HA were
    possible?
    What if high
    write
    throughput
    were possible?
    

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