How to resolve key conflicts with redis

Redis resolves key conflicts through the following mechanisms: 1. Atomicity: Ensure that write operations to a single key are either fully executed or not at all. 2. Queue: Put operations that write to the same key at the same time into the queue and execute in first-come, first-out order. 3. Exit policy: Delete the oldest or least important keys to make room for new keys. 4. Optimistic lock: The client performs a write after reading the key value. If the key value has changed, the write fails and retry.

How does Redis resolve key conflicts?

Redis key conflict refers to multiple clients trying to perform write operations on the same key at the same time. To solve this problem, Redis uses the following mechanism:

1. Atomicity

Redis uses atomic operations to ensure that writing operations to a single key are either fully executed or not at all. This means that the key cannot be accessed by other clients until the write operation is completed.

2. Queue

Redis puts these operations into the queue when multiple clients try to perform write operations on the same key at the same time. Queueing ensures that write operations are performed in first-come, first-out order to prevent conflicts.

3. Exit strategy

If too many writes are accumulated in the queue, Redis will use the eviction strategy to remove the oldest or least important keys, making room for the new keys. Here are some commonly used expulsion strategies:

• LRU (latest used): Removes the longest unused key.
• TTL (Expiration Time): Delete the timeout key.
• Random Evicted: Randomly delete keys.
• noeviction: No keys are deleted, which may cause Redis to run out of memory.

4. Use optimistic locks

Redis can use optimistic locking to further improve the performance of concurrent writes. Optimistic lock allows the client to read the key's value, perform a write operation, and then write the new value to the key. If other clients modify the key between the client reading the key's value and writing the new value, the write operation will fail and the client will try again.

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