(function() { "use strict" ; const memoryLimitMb = 1; const memoryLimitBytes = memoryLimitMb * 1024 * 1024; // Start mongod with reduced memory limit for the $group stage. const conn = MongoRunner.runMongod({ setParameter: { internalDocumentSourceGroupMaxMemoryBytes: memoryLimitBytes, internalQuerySlotBasedExecutionHashAggApproxMemoryUseInBytesBeforeSpill: memoryLimitBytes } }); const testDb = conn.getDB(jsTestName()); // Create a collection exceeding the memory limit. testDb.largeColl.drop(); const largeStr = "A" .repeat(1024 * 1024); // 1MB string for (let i = 0; i < memoryLimitMb + 1; ++i) assert .commandWorked(testDb.largeColl.insert({x: i, largeStr: largeStr + i})); const pipeline = [{$group: {_id: '$largeStr' , minId: {$min: '$_id' }}}]; // Make sure that the pipeline needs to spill to disk. assert .throwsWithCode(() => testDb.largeColl.aggregate(pipeline, {allowDiskUse: false }), ErrorCodes.QueryExceededMemoryLimitNoDiskUseAllowed); testDb.largeColl.aggregate(pipeline); MongoRunner.stopMongod(conn); })();