/**
* Test the way cache entries are added (either "active" or "inactive") to the plan cache.
*/
TEST_F(QueryStageCachedPlan, QueryStageCachedPlanAddsActiveCacheEntries) {
AutoGetCollectionForReadCommand ctx(&_opCtx, nss);
Collection* collection = ctx.getCollection();
ASSERT(collection);
// Never run - just used as a key for the cache's get() functions, since all of the other
// CanonicalQueries created in this test will have this shape.
const auto shapeCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 123}, b: {$gte: 123}}"));
// Query can be answered by either index on "a" or index on "b".
const auto noResultsCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 11}, b: {$gte: 11}}"));
// We shouldn't have anything in the plan cache for this shape yet.
PlanCache* cache = collection->infoCache()->getPlanCache();
ASSERT(cache);
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kNotPresent);
// Run the CachedPlanStage with a long-running child plan. Replanning should be
// triggered and an inactive entry will be added.
forceReplanning(collection, noResultsCq.get());
// Check for an inactive cache entry.
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kPresentInactive);
// The works should be 1 for the entry since the query we ran should not have any results.
auto entry = assertGet(cache->getEntry(*shapeCq));
size_t works = 1U;
ASSERT_EQ(entry->works, works);
const size_t kExpectedNumWorks = 10;
for (int i = 0; i < std::ceil(std::log(kExpectedNumWorks) / std::log(2)); ++i) {
works *= 2;
// Run another query of the same shape, which is less selective, and therefore takes
// longer).
auto someResultsCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 1}, b: {$gte: 0}}"));
forceReplanning(collection, someResultsCq.get());
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kPresentInactive);
// The works on the cache entry should have doubled.
entry = assertGet(cache->getEntry(*shapeCq));
ASSERT_EQ(entry->works, works);
}
// Run another query which takes less time, and be sure an active entry is created.
auto fewResultsCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 6}, b: {$gte: 0}}"));
forceReplanning(collection, fewResultsCq.get());
// Now there should be an active cache entry.
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kPresentActive);
entry = assertGet(cache->getEntry(*shapeCq));
// This will query will match {a: 6} through {a:9} (4 works), plus one for EOF = 5 works.
ASSERT_EQ(entry->works, 5U);
}
void run() {
AutoGetCollectionForRead ctx(&_txn, nss.ns());
Collection* collection = ctx.getCollection();
ASSERT(collection);
// Query can be answered by either index on "a" or index on "b".
auto statusWithCQ = CanonicalQuery::canonicalize(nss, fromjson("{a: {$gte: 8}, b: 1}"));
ASSERT_OK(statusWithCQ.getStatus());
const std::unique_ptr<CanonicalQuery> cq = std::move(statusWithCQ.getValue());
// We shouldn't have anything in the plan cache for this shape yet.
PlanCache* cache = collection->infoCache()->getPlanCache();
ASSERT(cache);
CachedSolution* rawCachedSolution;
ASSERT_NOT_OK(cache->get(*cq, &rawCachedSolution));
// Get planner params.
QueryPlannerParams plannerParams;
fillOutPlannerParams(&_txn, collection, cq.get(), &plannerParams);
// Queued data stage will return a failure during the cached plan trial period.
auto mockChild = stdx::make_unique<QueuedDataStage>(&_txn, &_ws);
mockChild->pushBack(PlanStage::FAILURE);
// High enough so that we shouldn't trigger a replan based on works.
const size_t decisionWorks = 50;
CachedPlanStage cachedPlanStage(
&_txn, collection, &_ws, cq.get(), plannerParams, decisionWorks, mockChild.release());
// This should succeed after triggering a replan.
PlanYieldPolicy yieldPolicy(nullptr, PlanExecutor::YIELD_MANUAL);
ASSERT_OK(cachedPlanStage.pickBestPlan(&yieldPolicy));
// Make sure that we get 2 legit results back.
size_t numResults = 0;
PlanStage::StageState state = PlanStage::NEED_TIME;
while (state != PlanStage::IS_EOF) {
WorkingSetID id = WorkingSet::INVALID_ID;
state = cachedPlanStage.work(&id);
ASSERT_NE(state, PlanStage::FAILURE);
ASSERT_NE(state, PlanStage::DEAD);
if (state == PlanStage::ADVANCED) {
WorkingSetMember* member = _ws.get(id);
ASSERT(cq->root()->matchesBSON(member->obj.value()));
numResults++;
}
}
ASSERT_EQ(numResults, 2U);
// Plan cache should still be empty, as we don't write to it when we replan a failed
// query.
ASSERT_NOT_OK(cache->get(*cq, &rawCachedSolution));
}
TEST_F(QueryStageCachedPlan, DeactivatesEntriesOnReplan) {
AutoGetCollectionForReadCommand ctx(&_opCtx, nss);
Collection* collection = ctx.getCollection();
ASSERT(collection);
// Never run - just used as a key for the cache's get() functions, since all of the other
// CanonicalQueries created in this test will have this shape.
const auto shapeCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 123}, b: {$gte: 123}}"));
// Query can be answered by either index on "a" or index on "b".
const auto noResultsCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 11}, b: {$gte: 11}}"));
// We shouldn't have anything in the plan cache for this shape yet.
PlanCache* cache = collection->infoCache()->getPlanCache();
ASSERT(cache);
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kNotPresent);
// Run the CachedPlanStage with a long-running child plan. Replanning should be
// triggered and an inactive entry will be added.
forceReplanning(collection, noResultsCq.get());
// Check for an inactive cache entry.
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kPresentInactive);
// Run the plan again, to create an active entry.
forceReplanning(collection, noResultsCq.get());
// The works should be 1 for the entry since the query we ran should not have any results.
ASSERT_EQ(cache->get(*noResultsCq.get()).state, PlanCache::CacheEntryState::kPresentActive);
auto entry = assertGet(cache->getEntry(*shapeCq));
size_t works = 1U;
ASSERT_EQ(entry->works, works);
// Run another query which takes long enough to evict the active cache entry. The current
// cache entry's works value is a very low number. When replanning is triggered, the cache
// entry will be deactivated, but the new plan will not overwrite it, since the new plan will
// have a higher works. Therefore, we will be left in an inactive entry which has had its works
// value doubled from 1 to 2.
auto highWorksCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 0}, b: {$gte:0}}"));
forceReplanning(collection, highWorksCq.get());
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kPresentInactive);
ASSERT_EQ(assertGet(cache->getEntry(*shapeCq))->works, 2U);
// Again, force replanning. This time run the initial query which finds no results. The multi
// planner will choose a plan with works value lower than the existing inactive
// entry. Replanning will thus deactivate the existing entry (it's already
// inactive so this is a noop), then create a new entry with a works value of 1.
forceReplanning(collection, noResultsCq.get());
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kPresentActive);
ASSERT_EQ(assertGet(cache->getEntry(*shapeCq))->works, 1U);
}
/**
* For a given query, get a runner. The runner could be a SingleSolutionRunner, a
* CachedQueryRunner, or a MultiPlanRunner, depending on the cache/query solver/etc.
*/
Status getRunner(QueryMessage& q, Runner** out) {
CanonicalQuery* rawCanonicalQuery = NULL;
// Canonicalize the query and wrap it in an auto_ptr so we don't leak it if something goes
// wrong.
Status status = CanonicalQuery::canonicalize(q, &rawCanonicalQuery);
if (!status.isOK()) { return status; }
verify(rawCanonicalQuery);
auto_ptr<CanonicalQuery> canonicalQuery(rawCanonicalQuery);
// Try to look up a cached solution for the query.
// TODO: Can the cache have negative data about a solution?
PlanCache* localCache = PlanCache::get(canonicalQuery->ns());
CachedSolution* cs = localCache->get(*canonicalQuery);
if (NULL != cs) {
// We have a cached solution. Hand the canonical query and cached solution off to the
// cached plan runner, which takes ownership of both.
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*cs->solution, &root, &ws));
*out = new CachedPlanRunner(canonicalQuery.release(), cs, root, ws);
return Status::OK();
}
// No entry in cache for the query. We have to solve the query ourself.
vector<QuerySolution*> solutions;
QueryPlanner::plan(*canonicalQuery, &solutions);
// We cannot figure out how to answer the query. Should this ever happen?
if (0 == solutions.size()) {
return Status(ErrorCodes::BadValue, "Can't create a plan for the canonical query " +
canonicalQuery->toString());
}
if (1 == solutions.size()) {
// Only one possible plan. Run it. Build the stages from the solution.
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*solutions[0], &root, &ws));
// And, run the plan.
*out = new SingleSolutionRunner(canonicalQuery.release(), solutions[0], root, ws);
return Status::OK();
}
else {
// Many solutions. Let the MultiPlanRunner pick the best, update the cache, and so on.
auto_ptr<MultiPlanRunner> mpr(new MultiPlanRunner(canonicalQuery.release()));
for (size_t i = 0; i < solutions.size(); ++i) {
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*solutions[i], &root, &ws));
// Takes ownership of all arguments.
mpr->addPlan(solutions[i], root, ws);
}
*out = mpr.release();
return Status::OK();
}
}
/**
* Test that hitting the cached plan stage trial period's threshold for work cycles causes the
* query to be replanned. Also verify that the replanning results in a new plan cache entry.
*/
TEST_F(QueryStageCachedPlan, QueryStageCachedPlanHitMaxWorks) {
AutoGetCollectionForReadCommand ctx(&_opCtx, nss);
Collection* collection = ctx.getCollection();
ASSERT(collection);
// Query can be answered by either index on "a" or index on "b".
auto qr = stdx::make_unique<QueryRequest>(nss);
qr->setFilter(fromjson("{a: {$gte: 8}, b: 1}"));
auto statusWithCQ = CanonicalQuery::canonicalize(opCtx(), std::move(qr));
ASSERT_OK(statusWithCQ.getStatus());
const std::unique_ptr<CanonicalQuery> cq = std::move(statusWithCQ.getValue());
// We shouldn't have anything in the plan cache for this shape yet.
PlanCache* cache = collection->infoCache()->getPlanCache();
ASSERT(cache);
ASSERT_EQ(cache->get(*cq).state, PlanCache::CacheEntryState::kNotPresent);
// Get planner params.
QueryPlannerParams plannerParams;
fillOutPlannerParams(&_opCtx, collection, cq.get(), &plannerParams);
// Set up queued data stage to take a long time before returning EOF. Should be long
// enough to trigger a replan.
const size_t decisionWorks = 10;
const size_t mockWorks =
1U + static_cast<size_t>(internalQueryCacheEvictionRatio * decisionWorks);
auto mockChild = stdx::make_unique<QueuedDataStage>(&_opCtx, &_ws);
for (size_t i = 0; i < mockWorks; i++) {
mockChild->pushBack(PlanStage::NEED_TIME);
}
CachedPlanStage cachedPlanStage(
&_opCtx, collection, &_ws, cq.get(), plannerParams, decisionWorks, mockChild.release());
// This should succeed after triggering a replan.
PlanYieldPolicy yieldPolicy(PlanExecutor::NO_YIELD,
_opCtx.getServiceContext()->getFastClockSource());
ASSERT_OK(cachedPlanStage.pickBestPlan(&yieldPolicy));
ASSERT_EQ(getNumResultsForStage(_ws, &cachedPlanStage, cq.get()), 2U);
// This time we expect to find something in the plan cache. Replans after hitting the
// works threshold result in a cache entry.
ASSERT_EQ(cache->get(*cq).state, PlanCache::CacheEntryState::kPresentInactive);
}
TEST_F(QueryStageCachedPlan, EntriesAreNotDeactivatedWhenInactiveEntriesDisabled) {
// Set the global flag for disabling active entries.
internalQueryCacheDisableInactiveEntries.store(true);
ON_BLOCK_EXIT([] { internalQueryCacheDisableInactiveEntries.store(false); });
AutoGetCollectionForReadCommand ctx(&_opCtx, nss);
Collection* collection = ctx.getCollection();
ASSERT(collection);
// Never run - just used as a key for the cache's get() functions, since all of the other
// CanonicalQueries created in this test will have this shape.
const auto shapeCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 123}, b: {$gte: 123}}"));
// Query can be answered by either index on "a" or index on "b".
const auto noResultsCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 11}, b: {$gte: 11}}"));
// We shouldn't have anything in the plan cache for this shape yet.
PlanCache* cache = collection->infoCache()->getPlanCache();
ASSERT(cache);
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kNotPresent);
// Run the CachedPlanStage with a long-running child plan. Replanning should be
// triggered and an _active_ entry will be added (since the disableInactiveEntries flag is on).
forceReplanning(collection, noResultsCq.get());
// Check for an inactive cache entry.
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kPresentActive);
// Run the plan again. The entry should still be active.
forceReplanning(collection, noResultsCq.get());
ASSERT_EQ(cache->get(*noResultsCq.get()).state, PlanCache::CacheEntryState::kPresentActive);
// Run another query which takes long enough to evict the active cache entry. After replanning
// is triggered, be sure that the the cache entry is still active.
auto highWorksCq =
canonicalQueryFromFilterObj(opCtx(), nss, fromjson("{a: {$gte: 0}, b: {$gte:0}}"));
forceReplanning(collection, highWorksCq.get());
ASSERT_EQ(cache->get(*shapeCq).state, PlanCache::CacheEntryState::kPresentActive);
}
/**
* Test that on failure, the cached plan stage replans the query but does not create a new cache
* entry.
*/
TEST_F(QueryStageCachedPlan, QueryStageCachedPlanFailure) {
AutoGetCollectionForReadCommand ctx(&_opCtx, nss);
Collection* collection = ctx.getCollection();
ASSERT(collection);
// Query can be answered by either index on "a" or index on "b".
auto qr = stdx::make_unique<QueryRequest>(nss);
qr->setFilter(fromjson("{a: {$gte: 8}, b: 1}"));
auto statusWithCQ = CanonicalQuery::canonicalize(opCtx(), std::move(qr));
ASSERT_OK(statusWithCQ.getStatus());
const std::unique_ptr<CanonicalQuery> cq = std::move(statusWithCQ.getValue());
// We shouldn't have anything in the plan cache for this shape yet.
PlanCache* cache = collection->infoCache()->getPlanCache();
ASSERT(cache);
ASSERT_EQ(cache->get(*cq).state, PlanCache::CacheEntryState::kNotPresent);
// Get planner params.
QueryPlannerParams plannerParams;
fillOutPlannerParams(&_opCtx, collection, cq.get(), &plannerParams);
// Queued data stage will return a failure during the cached plan trial period.
auto mockChild = stdx::make_unique<QueuedDataStage>(&_opCtx, &_ws);
mockChild->pushBack(PlanStage::FAILURE);
// High enough so that we shouldn't trigger a replan based on works.
const size_t decisionWorks = 50;
CachedPlanStage cachedPlanStage(
&_opCtx, collection, &_ws, cq.get(), plannerParams, decisionWorks, mockChild.release());
// This should succeed after triggering a replan.
PlanYieldPolicy yieldPolicy(PlanExecutor::NO_YIELD,
_opCtx.getServiceContext()->getFastClockSource());
ASSERT_OK(cachedPlanStage.pickBestPlan(&yieldPolicy));
ASSERT_EQ(getNumResultsForStage(_ws, &cachedPlanStage, cq.get()), 2U);
// Plan cache should still be empty, as we don't write to it when we replan a failed
// query.
ASSERT_EQ(cache->get(*cq).state, PlanCache::CacheEntryState::kNotPresent);
}
// static
Status PlanCacheListPlans::list(const PlanCache& planCache, const std::string& ns,
const BSONObj& cmdObj, BSONObjBuilder* bob) {
CanonicalQuery* cqRaw;
Status status = canonicalize(ns, cmdObj, &cqRaw);
if (!status.isOK()) {
return status;
}
scoped_ptr<CanonicalQuery> cq(cqRaw);
CachedSolution* crRaw;
Status result = planCache.get(*cq, &crRaw);
if (!result.isOK()) {
return result;
}
scoped_ptr<CachedSolution> cr(crRaw);
BSONArrayBuilder plansBuilder(bob->subarrayStart("plans"));
size_t numPlans = cr->plannerData.size();
for (size_t i = 0; i < numPlans; ++i) {
BSONObjBuilder planBob(plansBuilder.subobjStart());
// Create plan details field.
// Currently, simple string representationg of
// SolutionCacheData. Need to revisit format when we
// need to parse user-provided plan details for planCacheAddPlan.
SolutionCacheData* scd = cr->plannerData[i];
BSONObjBuilder detailsBob(planBob.subobjStart("details"));
detailsBob.append("solution", scd->toString());
detailsBob.doneFast();
// XXX: Fix these field values once we have fleshed out cache entries.
// reason should contain initial plan stats and score from ranking process.
// feedback should contain execution stats from running the query to completion.
planBob.append("reason", BSONObj());
planBob.append("feedback", BSONObj());
planBob.append("hint", scd->adminHintApplied);
}
plansBuilder.doneFast();
return Status::OK();
}
void run() {
AutoGetCollectionForRead ctx(&_txn, nss.ns());
Collection* collection = ctx.getCollection();
ASSERT(collection);
// Query can be answered by either index on "a" or index on "b".
auto statusWithCQ = CanonicalQuery::canonicalize(nss, fromjson("{a: {$gte: 8}, b: 1}"));
ASSERT_OK(statusWithCQ.getStatus());
const std::unique_ptr<CanonicalQuery> cq = std::move(statusWithCQ.getValue());
// We shouldn't have anything in the plan cache for this shape yet.
PlanCache* cache = collection->infoCache()->getPlanCache();
ASSERT(cache);
CachedSolution* rawCachedSolution;
ASSERT_NOT_OK(cache->get(*cq, &rawCachedSolution));
// Get planner params.
QueryPlannerParams plannerParams;
fillOutPlannerParams(&_txn, collection, cq.get(), &plannerParams);
// Set up queued data stage to take a long time before returning EOF. Should be long
// enough to trigger a replan.
const size_t decisionWorks = 10;
const size_t mockWorks =
1U + static_cast<size_t>(internalQueryCacheEvictionRatio * decisionWorks);
auto mockChild = stdx::make_unique<QueuedDataStage>(&_txn, &_ws);
for (size_t i = 0; i < mockWorks; i++) {
mockChild->pushBack(PlanStage::NEED_TIME);
}
CachedPlanStage cachedPlanStage(
&_txn, collection, &_ws, cq.get(), plannerParams, decisionWorks, mockChild.release());
// This should succeed after triggering a replan.
PlanYieldPolicy yieldPolicy(nullptr, PlanExecutor::YIELD_MANUAL);
ASSERT_OK(cachedPlanStage.pickBestPlan(&yieldPolicy));
// Make sure that we get 2 legit results back.
size_t numResults = 0;
PlanStage::StageState state = PlanStage::NEED_TIME;
while (state != PlanStage::IS_EOF) {
WorkingSetID id = WorkingSet::INVALID_ID;
state = cachedPlanStage.work(&id);
ASSERT_NE(state, PlanStage::FAILURE);
ASSERT_NE(state, PlanStage::DEAD);
if (state == PlanStage::ADVANCED) {
WorkingSetMember* member = _ws.get(id);
ASSERT(cq->root()->matchesBSON(member->obj.value()));
numResults++;
}
}
ASSERT_EQ(numResults, 2U);
// This time we expect to find something in the plan cache. Replans after hitting the
// works threshold result in a cache entry.
ASSERT_OK(cache->get(*cq, &rawCachedSolution));
const std::unique_ptr<CachedSolution> cachedSolution(rawCachedSolution);
}
/**
* For a given query, get a runner. The runner could be a SingleSolutionRunner, a
* CachedQueryRunner, or a MultiPlanRunner, depending on the cache/query solver/etc.
*/
Status getRunner(CanonicalQuery* rawCanonicalQuery, Runner** out) {
verify(rawCanonicalQuery);
auto_ptr<CanonicalQuery> canonicalQuery(rawCanonicalQuery);
// Try to look up a cached solution for the query.
// TODO: Can the cache have negative data about a solution?
PlanCache* localCache = PlanCache::get(canonicalQuery->ns());
if (NULL != localCache) {
CachedSolution* cs = localCache->get(*canonicalQuery);
if (NULL != cs) {
// We have a cached solution. Hand the canonical query and cached solution off to
// the cached plan runner, which takes ownership of both.
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*cs->solution, &root, &ws));
*out = new CachedPlanRunner(canonicalQuery.release(), cs, root, ws);
return Status::OK();
}
}
// No entry in cache for the query. We have to solve the query ourself.
// Get the indices that we could possibly use.
NamespaceDetails* nsd = nsdetails(canonicalQuery->ns().c_str());
// If this is NULL, there is no data but the query is valid. You're allowed to query for
// data on an empty collection and it's not an error. There just isn't any data...
if (NULL == nsd) {
const std::string& ns = canonicalQuery->ns();
*out = new EOFRunner(canonicalQuery.release(), ns);
return Status::OK();
}
// Tailable: If the query requests tailable the collection must be capped.
if (canonicalQuery->getParsed().hasOption(QueryOption_CursorTailable)) {
if (!nsd->isCapped()) {
return Status(ErrorCodes::BadValue,
"tailable cursor requested on non capped collection");
}
// If a sort is specified it must be equal to expectedSort.
const BSONObj expectedSort = BSON("$natural" << 1);
const BSONObj& actualSort = canonicalQuery->getParsed().getSort();
if (!actualSort.isEmpty() && !(actualSort == expectedSort)) {
return Status(ErrorCodes::BadValue,
"invalid sort specified for tailable cursor: "
+ actualSort.toString());
}
}
// If it's not NULL, we may have indices.
vector<IndexEntry> indices;
for (int i = 0; i < nsd->getCompletedIndexCount(); ++i) {
auto_ptr<IndexDescriptor> desc(CatalogHack::getDescriptor(nsd, i));
indices.push_back(IndexEntry(desc->keyPattern(), desc->isMultikey(), desc->isSparse(), desc->indexName()));
}
vector<QuerySolution*> solutions;
size_t options = QueryPlanner::DEFAULT;
if (storageGlobalParams.noTableScan) {
const string& ns = canonicalQuery->ns();
// There are certain cases where we ignore this restriction:
bool ignore = canonicalQuery->getQueryObj().isEmpty()
|| (string::npos != ns.find(".system."))
|| (0 == ns.find("local."));
if (!ignore) {
options |= QueryPlanner::NO_TABLE_SCAN;
}
}
else {
options |= QueryPlanner::INCLUDE_COLLSCAN;
}
QueryPlanner::plan(*canonicalQuery, indices, options, &solutions);
/*
for (size_t i = 0; i < solutions.size(); ++i) {
QLOG() << "solution " << i << " is " << solutions[i]->toString() << endl;
}
*/
// We cannot figure out how to answer the query. Should this ever happen?
if (0 == solutions.size()) {
return Status(ErrorCodes::BadValue, "Can't create a plan for the canonical query " +
canonicalQuery->toString());
}
if (1 == solutions.size()) {
// Only one possible plan. Run it. Build the stages from the solution.
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*solutions[0], &root, &ws));
// And, run the plan.
*out = new SingleSolutionRunner(canonicalQuery.release(), solutions[0], root, ws);
return Status::OK();
}
else {
// Many solutions. Let the MultiPlanRunner pick the best, update the cache, and so on.
auto_ptr<MultiPlanRunner> mpr(new MultiPlanRunner(canonicalQuery.release()));
for (size_t i = 0; i < solutions.size(); ++i) {
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*solutions[i], &root, &ws));
// Takes ownership of all arguments.
mpr->addPlan(solutions[i], root, ws);
}
*out = mpr.release();
return Status::OK();
}
}
/**
* For a given query, get a runner. The runner could be a SingleSolutionRunner, a
* CachedQueryRunner, or a MultiPlanRunner, depending on the cache/query solver/etc.
*/
Status getRunner(CanonicalQuery* rawCanonicalQuery, Runner** out, size_t plannerOptions) {
verify(rawCanonicalQuery);
auto_ptr<CanonicalQuery> canonicalQuery(rawCanonicalQuery);
// Try to look up a cached solution for the query.
// TODO: Can the cache have negative data about a solution?
PlanCache* localCache = PlanCache::get(canonicalQuery->ns());
if (NULL != localCache) {
CachedSolution* cs = localCache->get(*canonicalQuery);
if (NULL != cs) {
// We have a cached solution. Hand the canonical query and cached solution off to
// the cached plan runner, which takes ownership of both.
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*cs->solution, &root, &ws));
*out = new CachedPlanRunner(canonicalQuery.release(), cs, root, ws);
return Status::OK();
}
}
// No entry in cache for the query. We have to solve the query ourself.
// Get the indices that we could possibly use.
Database* db = cc().database();
verify( db );
Collection* collection = db->getCollection( canonicalQuery->ns() );
// This can happen as we're called by internal clients as well.
if (NULL == collection) {
const string& ns = canonicalQuery->ns();
*out = new EOFRunner(canonicalQuery.release(), ns);
return Status::OK();
}
// If we have an _id index we can use the idhack runner.
if (canUseIDHack(*canonicalQuery) && collection->getIndexCatalog()->findIdIndex()) {
*out = new IDHackRunner(collection, canonicalQuery.release());
return Status::OK();
}
// If it's not NULL, we may have indices. Access the catalog and fill out IndexEntry(s)
QueryPlannerParams plannerParams;
for (int i = 0; i < collection->getIndexCatalog()->numIndexesReady(); ++i) {
IndexDescriptor* desc = collection->getIndexCatalog()->getDescriptor( i );
plannerParams.indices.push_back(IndexEntry(desc->keyPattern(),
desc->isMultikey(),
desc->isSparse(),
desc->indexName()));
}
// Tailable: If the query requests tailable the collection must be capped.
if (canonicalQuery->getParsed().hasOption(QueryOption_CursorTailable)) {
if (!collection->isCapped()) {
return Status(ErrorCodes::BadValue,
"tailable cursor requested on non capped collection");
}
// If a sort is specified it must be equal to expectedSort.
const BSONObj expectedSort = BSON("$natural" << 1);
const BSONObj& actualSort = canonicalQuery->getParsed().getSort();
if (!actualSort.isEmpty() && !(actualSort == expectedSort)) {
return Status(ErrorCodes::BadValue,
"invalid sort specified for tailable cursor: "
+ actualSort.toString());
}
}
// Process the planning options.
plannerParams.options = plannerOptions;
if (storageGlobalParams.noTableScan) {
const string& ns = canonicalQuery->ns();
// There are certain cases where we ignore this restriction:
bool ignore = canonicalQuery->getQueryObj().isEmpty()
|| (string::npos != ns.find(".system."))
|| (0 == ns.find("local."));
if (!ignore) {
plannerParams.options |= QueryPlannerParams::NO_TABLE_SCAN;
}
}
if (!(plannerParams.options & QueryPlannerParams::NO_TABLE_SCAN)) {
plannerParams.options |= QueryPlannerParams::INCLUDE_COLLSCAN;
}
// If the caller wants a shard filter, make sure we're actually sharded.
if (plannerParams.options & QueryPlannerParams::INCLUDE_SHARD_FILTER) {
CollectionMetadataPtr collMetadata = shardingState.getCollectionMetadata(canonicalQuery->ns());
if (collMetadata) {
plannerParams.shardKey = collMetadata->getKeyPattern();
}
else {
// If there's no metadata don't bother w/the shard filter since we won't know what
// the key pattern is anyway...
plannerParams.options &= ~QueryPlannerParams::INCLUDE_SHARD_FILTER;
}
}
vector<QuerySolution*> solutions;
QueryPlanner::plan(*canonicalQuery, plannerParams, &solutions);
/*
for (size_t i = 0; i < solutions.size(); ++i) {
QLOG() << "solution " << i << " is " << solutions[i]->toString() << endl;
}
*/
// We cannot figure out how to answer the query. Should this ever happen?
if (0 == solutions.size()) {
return Status(ErrorCodes::BadValue, "No query solutions");
}
if (1 == solutions.size()) {
// Only one possible plan. Run it. Build the stages from the solution.
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*solutions[0], &root, &ws));
// And, run the plan.
*out = new SingleSolutionRunner(canonicalQuery.release(), solutions[0], root, ws);
return Status::OK();
}
else {
// Many solutions. Let the MultiPlanRunner pick the best, update the cache, and so on.
auto_ptr<MultiPlanRunner> mpr(new MultiPlanRunner(canonicalQuery.release()));
for (size_t i = 0; i < solutions.size(); ++i) {
WorkingSet* ws;
PlanStage* root;
verify(StageBuilder::build(*solutions[i], &root, &ws));
// Takes ownership of all arguments.
mpr->addPlan(solutions[i], root, ws);
}
*out = mpr.release();
return Status::OK();
}
}