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/**
* Tests that $sort stage reports the correct stats when explain is run with
* different verbosities.
*/
(function() {
"use strict";
load("jstests/libs/analyze_plan.js"); // For getAggPlanStages().
load("jstests/libs/sbe_util.js"); // For checkSBEEnabled.
const conn = MongoRunner.runMongod();
const db = conn.getDB("test");
const coll = db.explain_sort_stage_exec_stats;
coll.drop();
const isSbeEnabled = checkSBEEnabled(db);
const bigStr = Array(1025).toString(); // 1KB of ','
const lowMaxMemoryLimit = 5000;
const nDocs = 1000;
const bulk = coll.initializeUnorderedBulkOp();
for (let i = 1; i <= nDocs; i++) {
bulk.insert({_id: i, a: i, b: i, bigStr: bigStr});
}
assert.commandWorked(bulk.execute());
const pipelines = [
{sortUsesDocumentSources: false, pipeline: [{$sort: {_id: 1, b: -1}}]}, // no limit
{
sortUsesDocumentSources: true,
pipeline: [{$_internalInhibitOptimization: {}}, {$sort: {_id: 1, b: -1}}]
}, // no limit document sources
{
sortUsesDocumentSources: false,
pipeline: [{$sort: {_id: 1, b: -1}}, {$limit: nDocs / 10}]
}, // top k sorter
{
sortUsesDocumentSources: true,
pipeline:
[{$_internalInhibitOptimization: {}}, {$sort: {_id: 1, b: -1}}, {$limit: nDocs / 10}]
}, // top k sorter document sources
];
function checkSortSpillStats(explainOutput, shouldSpill, sortUsesDocumentSources) {
let execStage = {};
if (sortUsesDocumentSources) {
execStage = getAggPlanStage(explainOutput, "$sort");
} else if (isSbeEnabled) {
execStage = getAggPlanStage(explainOutput, "sort");
} else {
execStage = getAggPlanStage(explainOutput, "SORT");
}
assert.neq(null, execStage, explainOutput);
assert(execStage.hasOwnProperty("usedDisk"), execStage);
assert(execStage.hasOwnProperty("spills"), execStage);
assert(execStage.hasOwnProperty("spilledDataStorageSize"), execStage);
const usedDisk = execStage.usedDisk;
const spills = execStage.spills;
const spilledDataStorageSize = execStage.spilledDataStorageSize;
if (shouldSpill) {
assert(usedDisk, explainOutput);
assert.gt(spills, 0, explainOutput);
assert.gt(spilledDataStorageSize, 0, explainOutput);
} else {
assert(!usedDisk, explainOutput);
assert.eq(spills, 0, explainOutput);
assert.eq(spilledDataStorageSize, 0, explainOutput);
}
}
let explainOutput = {};
pipelines.forEach(function(pipeline) {
// Set MaxMemory low to force spill to disk.
const originalMemoryLimit = assert.commandWorked(db.adminCommand(
{setParameter: 1, internalQueryMaxBlockingSortMemoryUsageBytes: lowMaxMemoryLimit}));
explainOutput = coll.explain("executionStats").aggregate(pipeline.pipeline);
checkSortSpillStats(explainOutput, true /*shouldSpill*/, pipeline.sortUsesDocumentSources);
// Set MaxMemory to back to the original value.
assert.commandWorked(db.adminCommand(
{setParameter: 1, internalQueryMaxBlockingSortMemoryUsageBytes: originalMemoryLimit.was}));
explainOutput = coll.explain("executionStats").aggregate(pipeline.pipeline);
checkSortSpillStats(explainOutput, false /*shouldSpill*/, pipeline.sortUsesDocumentSources);
});
MongoRunner.stopMongod(conn);
}());
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