Why should point uploads be batched instead of sending one upsert request per point?

Each network request has fixed overhead: connection handling, serialization, request parsing, acknowledgement, and scheduling. Sending one point per request repeats that overhead millions of times.

Batching amortizes those costs across many points and gives Qdrant a larger unit of work for indexing and storage. This generally improves ingestion throughput and reduces application-side request overhead.

The trade-off is batch size. Very large batches can increase memory usage, request payload size, retry cost, and latency for individual failures. I would choose a starting size based on payload size and then benchmark throughput, CPU, memory, and tail latency.

A common mistake is assuming the largest possible batch is always fastest. Once batches become large enough, serialization, network limits, indexing contention, or memory pressure can dominate. The correct size is workload-dependent.