الاستمرارية والذاكرة والإخلاء

في هذا الدرس

know what survives a restart and what happens when memory is full.

الموضوعات المخطط لها

• RDB: periodic snapshots; fast restart, may lose the last minutes.
• AOF: log of writes, with fsync policies (every second, always); less loss, bigger files.
• No persistence is valid for a pure cache. Replication does not replace backups, and failover can lose recent writes.
• Set maxmemory and an eviction policy (allkeys-lru, allkeys-lfu, volatile-*, or noeviction).
• noeviction makes writes fail when full; a cache usually wants an allkeys-* policy.