Aggregation Pipeline Limits

Three numbers set the main limits on a pipeline: it can hold at most 1,000 stages, each document it returns can be at most 16 MB, and each stage can use only 100 MB of memory before it must write to disk or fail. We ran each case below on a MongoDB 8.0 test server, so the error messages are the real ones.

The tests need large documents, so this collection holds 150 documents of about 1 MB each, for about 150 MB of data. Run it only on a test server.

db.events.drop()

const payload = "x".repeat(1024 * 1024)

for (let i = 0; i < 150; i++) {
  db.events