Whenever indexed data changes, is the index update a blocking operation?

Question

Whenever indexed data changes, is the index update a blocking operation?

Answer

Index creation and updates are synchronous and provided that Redis has a single-threaded architecture, this means that any write to a key is monitored and Redis will invoke an index update that will take some CPU time. And will impact overall latency. If this becomes a limitation, adding more shards to the database can help reduce the writes overhead.

References

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