Attendees:

• Unknown User (eolivelli)
• Sijie Guo
  
• Unknown User (jujjuri)
• Unknown User (yzang)
• Rithin Shetty

NOTES

• Discussed BP-2: Resource Placement

  • Disk Capacity as weight. Can be extended to other metrics.

  • This feature can be enabled/disabled by a configuration flag

  • Client will query all the bookies to build the weight information
    

    • New protocol message

    • Watch for bookies removal and additional

  • Most of the logic is on client side, not on the bookies

  • Hotspot: (pick the solution 2)
    

  • • Solution 1: limit on N * min_weight

    • Solution 2: limit on N * median_weight

    • Solution 3: another dimension of weight (not going because of the get bookie info storm)

  • Protocol : Get bookie info request

    • There will be a connection concern when the number of clients and number of bookies grows.
      

  • • Gossip Protocol for collecting information

  • AutoRecovery

    • AutoRecovery is using client which it would automatically leverage the change.
  • Implementation

  • • UpdateBookieInfo - recalculating the weights

    • Rackware - no change to select rack logic

    • BookieInfoReader - Singleton per bookkeeper object

  • Stats and Monitoring

  • Rollout Plan

• Questions

  • BookieInfo (Unknown User (eolivelli))

    • Add label into the bookie info for multi-tenant placement
      

    • A generic properties

  • AutoRecovery (Unknown User (yzang))

    • Two different ways to auto recovery

    • Running autorecovery with bookies
    • Running autorecovery separatedly
      

  • Rack (Unknown User (yzang))

    • How to handle weighted rack placement? 
    • Propagated the weight information through the whole NetworkTopology

  • Connections

    • Gossip

    • Random backoff to avoid request storm
      

  • Alternatives

    • Zookeeper based

    • Let's add tickets to track enhancements
      

  • BookieInfoReader

    • Lazy initialization for write ledger handle