Storage-Offline group chat

• Storage requirements

• Storage model

  • Read amplification

  • Write amplication

    • Improve by only storing message id

    • Improve by only storing last message id

Storage requirements

• Requirement1: Query all group conversations a user participates in after a given timestamp.

• Requirement2: For each conversation, load all messages within that conversation created later than a given timestamp.

• Requirement3: For each conversation, load all participates inside it.

Storage model

• In group chat scenario (Except for those extremely big 100K+ groups -_-), typically read write ratio will be 100:1. So the storage model should better balance this factor to something like 50:50 or more evenly. So typically write amplification is used.

Read amplification

Write amplication

Improve by only storing message id

Improve by only storing last message id