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//
// Tests that serverStatus includes sharding statistics by default and the sharding statistics are
// indeed the correct values. Does not test the catalog cache portion of sharding statistics.
//
// @tags: [uses_transactions]
(function() {
'use strict';
load("jstests/libs/chunk_manipulation_util.js");
load("jstests/libs/parallelTester.js");
function ShardStat() {
this.countDonorMoveChunkStarted = 0;
this.countRecipientMoveChunkStarted = 0;
this.countDocsClonedOnRecipient = 0;
this.countDocsClonedOnDonor = 0;
this.countDocsDeletedOnDonor = 0;
}
function incrementStatsAndCheckServerShardStats(donor, recipient, numDocs) {
++donor.countDonorMoveChunkStarted;
donor.countDocsClonedOnDonor += numDocs;
++recipient.countRecipientMoveChunkStarted;
recipient.countDocsClonedOnRecipient += numDocs;
donor.countDocsDeletedOnDonor += numDocs;
const statsFromServerStatus = shardArr.map(function(shardVal) {
return shardVal.getDB('admin').runCommand({serverStatus: 1}).shardingStatistics;
});
for (let i = 0; i < shardArr.length; ++i) {
assert(statsFromServerStatus[i]);
assert(statsFromServerStatus[i].countStaleConfigErrors);
assert(statsFromServerStatus[i].totalCriticalSectionCommitTimeMillis);
assert(statsFromServerStatus[i].totalCriticalSectionTimeMillis);
assert(statsFromServerStatus[i].totalDonorChunkCloneTimeMillis);
assert(statsFromServerStatus[i].countDonorMoveChunkLockTimeout);
assert.eq(stats[i].countDonorMoveChunkStarted,
statsFromServerStatus[i].countDonorMoveChunkStarted);
assert.eq(stats[i].countDocsClonedOnRecipient,
statsFromServerStatus[i].countDocsClonedOnRecipient);
assert.eq(stats[i].countDocsClonedOnDonor,
statsFromServerStatus[i].countDocsClonedOnDonor);
assert.eq(stats[i].countDocsDeletedOnDonor,
statsFromServerStatus[i].countDocsDeletedOnDonor);
assert.eq(stats[i].countRecipientMoveChunkStarted,
statsFromServerStatus[i].countRecipientMoveChunkStarted);
}
}
function checkServerStatusMigrationLockTimeoutCount(shardConn, count) {
const shardStats =
assert.commandWorked(shardConn.adminCommand({serverStatus: 1})).shardingStatistics;
assert(shardStats.hasOwnProperty("countDonorMoveChunkLockTimeout"));
assert.eq(count, shardStats.countDonorMoveChunkLockTimeout);
}
function runConcurrentMoveChunk(host, ns, toShard) {
const mongos = new Mongo(host);
return mongos.adminCommand({moveChunk: ns, find: {_id: 1}, to: toShard});
}
function runConcurrentRead(host, dbName, collName) {
const mongos = new Mongo(host);
return mongos.getDB(dbName)[collName].find({_id: 5}).comment("concurrent read").itcount();
}
const dbName = "db";
const collName = "coll";
const st = new ShardingTest({shards: 2, mongos: 1});
const mongos = st.s0;
const admin = mongos.getDB("admin");
const coll = mongos.getCollection(dbName + "." + collName);
const numDocsToInsert = 3;
const shardArr = [st.shard0, st.shard1];
const stats = [new ShardStat(), new ShardStat()];
let numDocsInserted = 0;
assert.commandWorked(admin.runCommand({enableSharding: coll.getDB() + ""}));
st.ensurePrimaryShard(coll.getDB() + "", st.shard0.shardName);
assert.commandWorked(admin.runCommand({shardCollection: coll + "", key: {_id: 1}}));
assert.commandWorked(admin.runCommand({split: coll + "", middle: {_id: 0}}));
// Move chunk from shard0 to shard1 without docs.
assert.commandWorked(
mongos.adminCommand({moveChunk: coll + '', find: {_id: 1}, to: st.shard1.shardName}));
incrementStatsAndCheckServerShardStats(stats[0], stats[1], numDocsInserted);
// Insert docs and then move chunk again from shard1 to shard0.
for (let i = 0; i < numDocsToInsert; ++i) {
assert.writeOK(coll.insert({_id: i}));
++numDocsInserted;
}
assert.commandWorked(mongos.adminCommand(
{moveChunk: coll + '', find: {_id: 1}, to: st.shard0.shardName, _waitForDelete: true}));
incrementStatsAndCheckServerShardStats(stats[1], stats[0], numDocsInserted);
// Check that numbers are indeed cumulative. Move chunk from shard0 to shard1.
assert.commandWorked(mongos.adminCommand(
{moveChunk: coll + '', find: {_id: 1}, to: st.shard1.shardName, _waitForDelete: true}));
incrementStatsAndCheckServerShardStats(stats[0], stats[1], numDocsInserted);
// Move chunk from shard1 to shard0.
assert.commandWorked(mongos.adminCommand(
{moveChunk: coll + '', find: {_id: 1}, to: st.shard0.shardName, _waitForDelete: true}));
incrementStatsAndCheckServerShardStats(stats[1], stats[0], numDocsInserted);
//
// Tests for the count of migrations aborting from lock timeouts.
//
// Lower migrationLockAcquisitionMaxWaitMS so migrations time out more quickly.
const donorConn = st.rs0.getPrimary();
const lockParameterRes = assert.commandWorked(
donorConn.adminCommand({getParameter: 1, migrationLockAcquisitionMaxWaitMS: 1}));
const originalMigrationLockTimeout = lockParameterRes.migrationLockAcquisitionMaxWaitMS;
assert.commandWorked(
donorConn.adminCommand({setParameter: 1, migrationLockAcquisitionMaxWaitMS: 2 * 1000}));
// Counter starts at 0.
checkServerStatusMigrationLockTimeoutCount(donorConn, 0);
// Pause a migration before entering the critical section.
pauseMoveChunkAtStep(donorConn, moveChunkStepNames.reachedSteadyState);
let moveChunkThread = new ScopedThread(
runConcurrentMoveChunk, st.s.host, dbName + "." + collName, st.shard1.shardName);
moveChunkThread.start();
waitForMoveChunkStep(donorConn, moveChunkStepNames.reachedSteadyState);
// Start a transaction and insert to the migrating chunk to block entering the critical section.
const session = mongos.startSession();
session.startTransaction();
assert.commandWorked(session.getDatabase(dbName)[collName].insert({_id: 5}));
// Unpause the migration and it should time out entering the critical section.
unpauseMoveChunkAtStep(donorConn, moveChunkStepNames.reachedSteadyState);
moveChunkThread.join();
assert.commandFailedWithCode(moveChunkThread.returnData(), ErrorCodes.LockTimeout);
// Clean up the transaction and verify the counter was incremented in serverStatus.
assert.commandWorked(session.abortTransaction_forTesting());
checkServerStatusMigrationLockTimeoutCount(donorConn, 1);
// Writes are blocked during the critical section, so insert a document into the chunk to be
// moved before the migration begins that can be read later.
assert.commandWorked(st.s.getDB(dbName)[collName].insert({_id: 5}));
// Pause a migration after entering the critical section, but before entering the commit phase.
pauseMoveChunkAtStep(donorConn, moveChunkStepNames.chunkDataCommitted);
moveChunkThread = new ScopedThread(
runConcurrentMoveChunk, st.s.host, dbName + "." + collName, st.shard1.shardName);
moveChunkThread.start();
waitForMoveChunkStep(donorConn, moveChunkStepNames.chunkDataCommitted);
// Pause a read while it's holding locks so the migration can't commit.
assert.commandWorked(donorConn.adminCommand(
{configureFailPoint: "waitInFindBeforeMakingBatch", mode: "alwaysOn"}));
const concurrentRead = new ScopedThread(runConcurrentRead, st.s.host, dbName, collName);
concurrentRead.start();
assert.soon(function() {
const curOpResults = assert.commandWorked(donorConn.adminCommand({currentOp: 1}));
return curOpResults.inprog.some(op => op["command"]["comment"] === "concurrent read");
});
// Unpause the migration and it should time out entering the commit phase.
unpauseMoveChunkAtStep(donorConn, moveChunkStepNames.chunkDataCommitted);
moveChunkThread.join();
assert.commandFailedWithCode(moveChunkThread.returnData(), ErrorCodes.LockTimeout);
// Let the read finish and verify the counter was incremented in serverStatus.
assert.commandWorked(
donorConn.adminCommand({configureFailPoint: "waitInFindBeforeMakingBatch", mode: "off"}));
concurrentRead.join();
assert.eq(1, concurrentRead.returnData());
checkServerStatusMigrationLockTimeoutCount(donorConn, 2);
assert.commandWorked(donorConn.adminCommand(
{setParameter: 1, migrationLockAcquisitionMaxWaitMS: originalMigrationLockTimeout}));
st.stop();
})();
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