Node.js · interactive

Streams and backpressure

The producer wants to write faster than the consumer can read. The high water mark is the buffer's limit. Cross it, and the producer pauses.

Producer

writes 8/tick

Buffer

5 / 10 bytes

Consumer

reads 3/tick

Flowing. Wrote 8, read 3, 5 bytes waiting.

Bytes written per tick8Bytes read per tick3High water mark10Pause at this many unread bytesTick 1 of 8

1
If the stream is flowing, the producer adds bytes to the buffer.
wrote 8 this tick · 8 B/tick in the panel
2
3
4

In production

Tools and technologies

Backpressure appears anywhere a producer can outrun a consumer — not only in Node streams.

Not tied to one language — use these names when you search docs or design a system.