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/**
* Test that when replanning happens due to blocking sort's memory limit, we include
* replanReason: "cached plan returned: ..." in the profiling data.
* @tags: [requires_profiling]
*/
(function() {
"use strict";
load("jstests/libs/profiler.js");
const conn = MongoRunner.runMongod({
// Disallow blocking sort, by setting the memory limit very low (1 byte).
setParameter: "internalQueryExecMaxBlockingSortBytes=1"
});
const db = conn.getDB("test");
const coll = db.plan_cache_replan_sort;
coll.drop();
// Ensure a plan with a sort stage gets cached.
assert.commandWorked(coll.createIndex({x: 1}));
assert.commandWorked(coll.createIndex({y: 1}));
const docs = Array.from({length: 20}, (_, i) => ({x: 7, y: i}));
assert.commandWorked(coll.insert(docs));
// { x: 5 } is very selective because it matches 0 documents, so the x index will win.
// This will succeed despite the low memory limit on sort, because the sort stage will see zero
// documents.
assert.eq(0, coll.find({x: 5}).sort({y: 1}).itcount());
const cachedPlans = coll.getPlanCache().getPlansByQuery({x: 5}, {}, {y: 1}).plans;
assert.lte(1, cachedPlans.length, cachedPlans);
const winningPlan = cachedPlans[0];
assert.eq("SORT", winningPlan.reason.stats.stage, cachedPlans);
// Assert we "replan", by running the same query with different parameters.
// This time the filter is not selective at all.
db.setProfilingLevel(2);
assert.eq(20, coll.find({x: 7}).sort({y: 1}).itcount());
const profileObj = getLatestProfilerEntry(db, {op: "query"});
assert.eq(profileObj.ns, coll.getFullName(), profileObj);
assert.eq(profileObj.replanned, true, profileObj);
assert.eq(
profileObj.replanReason,
"cached plan returned: OperationFailed: Sort operation used more than the maximum 1 bytes of " +
"RAM. Add an index, or specify a smaller limit.",
profileObj);
MongoRunner.stopMongod(conn);
}());
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