SERVER-71255 Remove clearEntries param from telemetry operator

4 files changed, 21 insertions, 88 deletions

diff --git a/src/mongo/db/pipeline/document_source_telemetry.cpp b/src/mongo/db/pipeline/document_source_telemetry.cpp
index c03406fa097..36acd596241 100644
--- a/src/mongo/db/pipeline/document_source_telemetry.cpp
+++ b/src/mongo/db/pipeline/document_source_telemetry.cpp
@@ -33,9 +33,6 @@
 #include "mongo/util/assert_util.h"
 
 namespace mongo {
-namespace {
-const StringData kClearEntriesFieldName = "clearEntries"_sd;
-}  // namespace
 
 REGISTER_DOCUMENT_SOURCE(telemetry,
                          DocumentSourceTelemetry::LiteParsed::parse,
@@ -49,26 +46,12 @@ std::unique_ptr<DocumentSourceTelemetry::LiteParsed> DocumentSourceTelemetry::Li
                           << " value must be an object. Found: " << typeName(spec.type()),
             spec.type() == BSONType::Object);
 
-    auto clearEntries = false;
-
-    for (auto&& elem : spec.embeddedObject()) {
-        const auto fieldName = elem.fieldNameStringData();
-        if (fieldName == "clearEntries"_sd) {
-            uassert(
-                ErrorCodes::TypeMismatch,
-                str::stream() << "The 'clearEntries' parameter of the $telemetry stage must be a "
-                                 "boolean. Instead found: "
-                              << typeName(elem.type()),
-                elem.type() == BSONType::Bool);
-            clearEntries = elem.boolean();
-        } else {
-            uasserted(ErrorCodes::FailedToParse,
-                      str::stream()
-                          << "Unrecognized option '" << fieldName << "' in $telemetry stage.");
-        }
-    }
+    uassert(ErrorCodes::FailedToParse,
+            str::stream() << kStageName
+                          << " parameters object must be empty. Found: " << typeName(spec.type()),
+            spec.embeddedObject().isEmpty());
 
-    return std::make_unique<DocumentSourceTelemetry::LiteParsed>(spec.fieldName(), clearEntries);
+    return std::make_unique<DocumentSourceTelemetry::LiteParsed>(spec.fieldName());
 }
 
 boost::intrusive_ptr<DocumentSource> DocumentSourceTelemetry::createFromBson(
@@ -78,48 +61,27 @@ boost::intrusive_ptr<DocumentSource> DocumentSourceTelemetry::createFromBson(
                           << " value must be an object. Found: " << typeName(spec.type()),
             spec.type() == BSONType::Object);
 
+    uassert(ErrorCodes::FailedToParse,
+            str::stream() << kStageName
+                          << " parameters object must be empty. Found: " << typeName(spec.type()),
+            spec.embeddedObject().isEmpty());
+
     const NamespaceString& nss = pExpCtx->ns;
 
     uassert(ErrorCodes::InvalidNamespace,
             "$telemetry must be run against the 'admin' database with {aggregate: 1}",
             nss.db() == NamespaceString::kAdminDb && nss.isCollectionlessAggregateNS());
 
-    auto clearEntries = false;
-
-    for (auto&& elem : spec.embeddedObject()) {
-        const auto fieldName = elem.fieldNameStringData();
-        if (fieldName == "clearEntries"_sd) {
-            uassert(
-                ErrorCodes::TypeMismatch,
-                str::stream() << "The 'clearEntries' parameter of the $telemetry stage must be a "
-                                 "boolean. Instead found: "
-                              << typeName(elem.type()),
-                elem.type() == BSONType::Bool);
-            clearEntries = elem.boolean();
-        } else {
-            uasserted(ErrorCodes::FailedToParse,
-                      str::stream()
-                          << "Unrecognized option '" << fieldName << "' in $telemetry stage.");
-        }
-    }
-
-    return new DocumentSourceTelemetry(pExpCtx, clearEntries);
+    return new DocumentSourceTelemetry(pExpCtx);
 }
 
 Value DocumentSourceTelemetry::serialize(boost::optional<ExplainOptions::Verbosity> explain) const {
-    return Value{Document{{kStageName, Document{{kClearEntriesFieldName, Value(_clearEntries)}}}}};
+    return Value{Document{{kStageName, Document{}}}};
 }
 
 void DocumentSourceTelemetry::buildTelemetryStoreIterator() {
     TelemetryStore* telemetryStore = [&]() {
-        if (_clearEntries) {
-            // Save the telemetry store to a member variable to be destroyed with the document
-            // source.
-            _telemetryStore = resetTelemetryStore(getContext()->opCtx->getServiceContext());
-            return &**_telemetryStore;
-        } else {
-            return getTelemetryStoreForRead(getContext()->opCtx->getServiceContext()).first;
-        }
+        return getTelemetryStoreForRead(getContext()->opCtx->getServiceContext()).first;
     }();
 
     // Here we start a new thread which runs until the document source finishes iterating the
diff --git a/src/mongo/db/pipeline/document_source_telemetry.h b/src/mongo/db/pipeline/document_source_telemetry.h
index 7d9bb55997c..d3a7dfd78e2 100644
--- a/src/mongo/db/pipeline/document_source_telemetry.h
+++ b/src/mongo/db/pipeline/document_source_telemetry.h
@@ -45,8 +45,8 @@ public:
         static std::unique_ptr<LiteParsed> parse(const NamespaceString& nss,
                                                  const BSONElement& spec);
 
-        LiteParsed(std::string parseTimeName, bool clearEntries)
-            : LiteParsedDocumentSource(std::move(parseTimeName)), _clearEntries(clearEntries) {}
+        LiteParsed(std::string parseTimeName)
+            : LiteParsedDocumentSource(std::move(parseTimeName)) {}
 
         stdx::unordered_set<NamespaceString> getInvolvedNamespaces() const override {
             return stdx::unordered_set<NamespaceString>();
@@ -69,9 +69,6 @@ public:
         void assertSupportsMultiDocumentTransaction() const {
             transactionNotSupported(kStageName);
         }
-
-    private:
-        const bool _clearEntries;
     };
 
     static boost::intrusive_ptr<DocumentSource> createFromBson(
@@ -172,16 +169,13 @@ private:
         stdx::condition_variable _waitForEmpty;
     };
 
-    DocumentSourceTelemetry(const boost::intrusive_ptr<ExpressionContext>& expCtx,
-                            bool clearEntries)
-        : DocumentSource(kStageName, expCtx), _clearEntries(clearEntries) {}
+    DocumentSourceTelemetry(const boost::intrusive_ptr<ExpressionContext>& expCtx)
+        : DocumentSource(kStageName, expCtx) {}
 
     GetNextResult doGetNext() final;
 
     void buildTelemetryStoreIterator();
 
-    const bool _clearEntries;
-
     bool _initialized = false;
 
     /**
diff --git a/src/mongo/db/pipeline/document_source_telemetry_test.cpp b/src/mongo/db/pipeline/document_source_telemetry_test.cpp
index 0d5814c7c1c..9d8f2ad7e26 100644
--- a/src/mongo/db/pipeline/document_source_telemetry_test.cpp
+++ b/src/mongo/db/pipeline/document_source_telemetry_test.cpp
@@ -77,13 +77,6 @@ TEST_F(DocumentSourceTelemetryTest, ShouldFailToParseIfNotRunWithAggregateOne) {
                        ErrorCodes::InvalidNamespace);
 }
 
-TEST_F(DocumentSourceTelemetryTest, ShouldFailToParseClearEntriesIfNotBoolean) {
-    ASSERT_THROWS_CODE(DocumentSourceTelemetry::createFromBson(
-                           fromjson("{$telemetry: {clearEntries: 1}}").firstElement(), getExpCtx()),
-                       AssertionException,
-                       ErrorCodes::TypeMismatch);
-}
-
 TEST_F(DocumentSourceTelemetryTest, ShouldFailToParseIfUnrecognisedParameterSpecified) {
     ASSERT_THROWS_CODE(DocumentSourceTelemetry::createFromBson(
                            fromjson("{$telemetry: {foo: true}}").firstElement(), getExpCtx()),
@@ -91,27 +84,11 @@ TEST_F(DocumentSourceTelemetryTest, ShouldFailToParseIfUnrecognisedParameterSpec
                        ErrorCodes::FailedToParse);
 }
 
-TEST_F(DocumentSourceTelemetryTest, ShouldParseAndSerializeNonDefaultOptionalArguments) {
-    auto obj = fromjson("{$telemetry: {clearEntries: true}}");
-    auto doc = DocumentSourceTelemetry::createFromBson(obj.firstElement(), getExpCtx());
-    auto telemetryOp = static_cast<DocumentSourceTelemetry*>(doc.get());
-    auto expected = Document{{"$telemetry", Document{{"clearEntries", true}}}};
-    ASSERT_DOCUMENT_EQ(telemetryOp->serialize().getDocument(), expected);
-}
-
-TEST_F(DocumentSourceTelemetryTest, ShouldParseAndSerializeDefaultOptionalArguments) {
-    auto obj = fromjson("{$telemetry: {clearEntries: false}}");
-    auto doc = DocumentSourceTelemetry::createFromBson(obj.firstElement(), getExpCtx());
-    auto telemetryOp = static_cast<DocumentSourceTelemetry*>(doc.get());
-    auto expected = Document{{"$telemetry", Document{{"clearEntries", false}}}};
-    ASSERT_DOCUMENT_EQ(telemetryOp->serialize().getDocument(), expected);
-}
-
-TEST_F(DocumentSourceTelemetryTest, ShouldSerializeOmittedOptionalArguments) {
+TEST_F(DocumentSourceTelemetryTest, ParseAndSerialize) {
     auto obj = fromjson("{$telemetry: {}}");
     auto doc = DocumentSourceTelemetry::createFromBson(obj.firstElement(), getExpCtx());
     auto telemetryOp = static_cast<DocumentSourceTelemetry*>(doc.get());
-    auto expected = Document{{"$telemetry", Document{{"clearEntries", false}}}};
+    auto expected = Document{{"$telemetry", Document{}}};
     ASSERT_DOCUMENT_EQ(telemetryOp->serialize().getDocument(), expected);
 }
 
diff --git a/src/mongo/db/query/query_knobs.idl b/src/mongo/db/query/query_knobs.idl
index c247bdabc47..0b743fc94a3 100644
--- a/src/mongo/db/query/query_knobs.idl
+++ b/src/mongo/db/query/query_knobs.idl
@@ -964,11 +964,11 @@ server_parameters:
       cache. This will accept values in either of the following formats:
       1. <number>% indicates a percentage of the physical memory available to the process. E.g.: 15%.
       2. <number>(MB|GB), indicates the amount of memory in MB or GB. E.g.: 1.5GB, 100MB.
-      The default value is 5%, which means 5% of the physical memory available to the process."
+      The default value is 1%, which means 1% of the physical memory available to the process."
     set_at: [ startup, runtime ]
     cpp_varname: "queryTelemetryStoreSize"
     cpp_vartype: synchronized_value<std::string>
-    default: "5%"
+    default: "1%"
     on_update: telemetry_util::onTelemetryStoreSizeUpdate
     validator:
       callback: telemetry_util::validateTelemetryStoreSize