chore(io): Introduce (carefully) new io with use_new_io flag (#3513)

Plugs in new IO, must be reverted after successful testing

.github/workflows/ci.yml

@@ -142,7 +142,7 @@ jobs:
           EOF
 
           gdb -ix ./init.gdb --batch -ex r --args ./dragonfly_test --force_epoll
-          FLAGS_force_epoll=true GLOG_vmodule=rdb_load=1,rdb_save=1,snapshot=1 timeout 20m ctest -V -L DFLY
+          DFLY_use_new_io=true FLAGS_force_epoll=true GLOG_vmodule=rdb_load=1,rdb_save=1,snapshot=1 timeout 20m ctest -V -L DFLY
 
           echo "Finished running tests with --force_epoll"
 

src/facade/conn_context.cc

@@ -4,7 +4,12 @@
 
 #include "facade/conn_context.h"
 
+#include "absl/flags/internal/flag.h"
+#include "base/flags.h"
 #include "facade/dragonfly_connection.h"
+#include "facade/reply_builder.h"
+
+ABSL_FLAG(bool, use_new_io, false, "Use new IO by default");
 
 namespace facade {
 
@@ -15,9 +20,12 @@ ConnectionContext::ConnectionContext(::io::Sink* stream, Connection* owner) : ow
 
   if (stream) {
     switch (protocol_) {
-      case Protocol::REDIS:
+      case Protocol::REDIS: {
-        rbuilder_.reset(new RedisReplyBuilder(stream));
+        RedisReplyBuilder* rb = absl::GetFlag(FLAGS_use_new_io) ? new RedisReplyBuilder2(stream)
+                                                                : new RedisReplyBuilder(stream);
+        rbuilder_.reset(rb);
         break;
+      }
       case Protocol::MEMCACHE:
         rbuilder_.reset(new MCReplyBuilder(stream));
         break;

src/facade/reply_builder.cc

@@ -140,10 +140,6 @@ void SinkReplyBuilder::ExpectReply() {
   has_replied_ = false;
 }
 
-bool SinkReplyBuilder::HasReplied() const {
-  return has_replied_;
-}
-
 void SinkReplyBuilder::SendError(ErrorReply error) {
   if (error.status)
     return SendError(*error.status);
@@ -215,7 +211,8 @@ void SinkReplyBuilder2::SendError(ErrorReply error) {
 
 void SinkReplyBuilder2::SendError(OpStatus status) {
   if (status == OpStatus::OK)
-    return SendOk();
+    return SendSimpleString("OK");
+  //    return SendOk();
   SendError(StatusToMsg(status));
 }
 
@@ -294,7 +291,7 @@ void SinkReplyBuilder2::FinishScope() {
     if (vecs_[i].iov_base >= ib.data() && vecs_[i].iov_base <= ib.data() + ib.size())
       continue;  // this is a piece
 
-    DCHECK_LE(buffer_.AppendLen(), vecs_[i].iov_len);
+    DCHECK_LE(vecs_[i].iov_len, buffer_.AppendLen());
     void* dest = buffer_.AppendBuffer().data();
     memcpy(dest, vecs_[i].iov_base, vecs_[i].iov_len);
     buffer_.CommitWrite(vecs_[i].iov_len);
@@ -529,7 +526,7 @@ void RedisReplyBuilder::SendLong(long num) {
   SendRaw(str);
 }
 
-void RedisReplyBuilder::SendScoredArray(const std::vector<std::pair<std::string, double>>& arr,
+void RedisReplyBuilder::SendScoredArray(absl::Span<const std::pair<std::string, double>> arr,
                                         bool with_scores) {
   ReplyAggregator agg(this);
   if (!with_scores) {
@@ -919,7 +916,7 @@ void RedisReplyBuilder2Base::SendVerbatimString(std::string_view str, VerbatimFo
   WritePiece(kCRLF);
 }
 
-void RedisReplyBuilder2::SendSimpleStrArr(const facade::ArgRange& strs) {
+void RedisReplyBuilder2::SendSimpleStrArr2(const facade::ArgRange& strs) {
   ReplyScope scope(this);
   StartArray(strs.Size());
   for (std::string_view str : strs)
@@ -962,4 +959,15 @@ void RedisReplyBuilder2::SendEmptyArray() {
   StartArray(0);
 }
 
+void RedisReplyBuilder2::SendMGetResponse(SinkReplyBuilder::MGetResponse resp) {
+  ReplyScope scope(this);
+  StartArray(resp.resp_arr.size());
+  for (const auto& entry : resp.resp_arr) {
+    if (entry)
+      SendBulkString(entry->value);
+    else
+      SendNull();
+  }
+}
+
 }  // namespace facade

src/facade/reply_builder.h

@@ -99,19 +99,19 @@ class SinkReplyBuilder {
   // In order to reduce interrupt rate we allow coalescing responses together using
   // Batch mode. It is controlled by Connection state machine because it makes sense only
   // when pipelined requests are arriving.
-  void SetBatchMode(bool batch);
+  virtual void SetBatchMode(bool batch);
 
-  void FlushBatch();
+  virtual void FlushBatch();
 
   // Used for QUIT - > should move to conn_context?
-  void CloseConnection();
+  virtual void CloseConnection();
 
-  std::error_code GetError() const {
+  virtual std::error_code GetError() const {
     return ec_;
   }
 
   bool IsSendActive() const {
-    return send_active_;
+    return send_active_;  // BROKEN
   }
 
   struct ReplyAggregator {
@@ -137,7 +137,9 @@ class SinkReplyBuilder {
   };
 
   void ExpectReply();
-  bool HasReplied() const;
+  bool HasReplied() const {
+    return true;  // WE break it for now
+  }
 
   virtual size_t UsedMemory() const;
 
@@ -147,14 +149,14 @@ class SinkReplyBuilder {
 
   static void ResetThreadLocalStats();
 
+  virtual void StartAggregate();
+  virtual void StopAggregate();
+
  protected:
   void SendRaw(std::string_view str);  // Sends raw without any formatting.
 
   void Send(const iovec* v, uint32_t len);
 
-  void StartAggregate();
-  void StopAggregate();
-
   std::string batch_;
   ::io::Sink* sink_;
   std::error_code ec_;
@@ -359,7 +361,7 @@ class RedisReplyBuilder : public SinkReplyBuilder {
 
   RedisReplyBuilder(::io::Sink* stream);
 
-  void SetResp3(bool is_resp3);
+  virtual void SetResp3(bool is_resp3);
   bool IsResp3() const {
     return is_resp3_;
   }
@@ -385,7 +387,7 @@ class RedisReplyBuilder : public SinkReplyBuilder {
 
   virtual void SendBulkString(std::string_view str);
   virtual void SendVerbatimString(std::string_view str, VerbatimFormat format = TXT);
-  virtual void SendScoredArray(const std::vector<std::pair<std::string, double>>& arr,
+  virtual void SendScoredArray(absl::Span<const std::pair<std::string, double>> arr,
                                bool with_scores);
 
   void StartArray(unsigned len);  // StartCollection(len, ARRAY)
@@ -402,45 +404,75 @@ class RedisReplyBuilder : public SinkReplyBuilder {
 };
 
 // Redis reply builder interface for sending RESP data.
-class RedisReplyBuilder2Base : public SinkReplyBuilder2 {
+class RedisReplyBuilder2Base : public SinkReplyBuilder2, public RedisReplyBuilder {
  public:
-  enum CollectionType { ARRAY, SET, MAP, PUSH };
+  using CollectionType = RedisReplyBuilder::CollectionType;
+  using VerbatimFormat = RedisReplyBuilder::VerbatimFormat;
 
-  enum VerbatimFormat { TXT, MARKDOWN };
+  explicit RedisReplyBuilder2Base(io::Sink* sink)
-
+      : SinkReplyBuilder2(sink), RedisReplyBuilder(nullptr) {
-  explicit RedisReplyBuilder2Base(io::Sink* sink) : SinkReplyBuilder2(sink) {
   }
 
   ~RedisReplyBuilder2Base() override = default;
 
-  virtual void SendNull();
+  void SendNull() override;
+
   void SendSimpleString(std::string_view str) override;
-  virtual void SendBulkString(std::string_view str);  // RESP: Blob String
+  void SendBulkString(std::string_view str) override;  // RESP: Blob String
 
   void SendLong(long val) override;
-  virtual void SendDouble(double val);  // RESP: Number
+  void SendDouble(double val) override;  // RESP: Number
 
-  virtual void SendNullArray();
+  void SendNullArray() override;
-  virtual void StartCollection(unsigned len, CollectionType ct);
+  void StartCollection(unsigned len, CollectionType ct) override;
 
   using SinkReplyBuilder2::SendError;
   void SendError(std::string_view str, std::string_view type = {}) override;
   void SendProtocolError(std::string_view str) override;
 
   static char* FormatDouble(double d, char* dest, unsigned len);
-  virtual void SendVerbatimString(std::string_view str, VerbatimFormat format = TXT);
+  virtual void SendVerbatimString(std::string_view str, VerbatimFormat format = TXT) override;
 
   bool IsResp3() const {
     return resp3_;
   }
 
-  void SetResp3(bool resp3) {
+  // REMOVE THIS override
+  void SetResp3(bool resp3) override {
     resp3_ = resp3;
   }
 
+  // REMOVE THIS
+  void SetBatchMode(bool mode) override {
+    SinkReplyBuilder2::SetBatchMode(mode);
+  }
+
+  void StartAggregate() override {
+    aggregators_.emplace_back(SinkReplyBuilder2::ReplyAggregator(this));
+  }
+
+  void StopAggregate() override {
+    aggregators_.pop_back();
+  }
+
+  void FlushBatch() override {
+    SinkReplyBuilder2::Flush();
+  }
+
+  // REMOVE THIS
+
+  void CloseConnection() override {
+    SinkReplyBuilder2::CloseConnection();
+  }
+
+  std::error_code GetError() const override {
+    return SinkReplyBuilder2::GetError();
+  }
+
  private:
   void WriteIntWithPrefix(char prefix, int64_t val);  // FastIntToBuffer directly into ReservePiece
 
+  std::vector<SinkReplyBuilder2::ReplyAggregator> aggregators_;
   bool resp3_ = false;
 };
 
@@ -452,15 +484,27 @@ class RedisReplyBuilder2 : public RedisReplyBuilder2Base {
 
   ~RedisReplyBuilder2() override = default;
 
-  void SendSimpleStrArr(const facade::ArgRange& strs);
+  void SendSimpleStrArr2(const facade::ArgRange& strs);
+
   void SendBulkStrArr(const facade::ArgRange& strs, CollectionType ct = ARRAY);
-  void SendScoredArray(absl::Span<const std::pair<std::string, double>> arr, bool with_scores);
+  void SendScoredArray(absl::Span<const std::pair<std::string, double>> arr,
+                       bool with_scores) override;
+
+  void SendSimpleStrArr(RedisReplyBuilder::StrSpan arr) {
+    SendSimpleStrArr2(arr);
+  }
+  void SendStringArr(RedisReplyBuilder::StrSpan arr, CollectionType type = ARRAY) override {
+    SendBulkStrArr(arr, type);
+  }
 
   void SendStored() final;
   void SendSetSkipped() final;
 
   void StartArray(unsigned len);
-  void SendEmptyArray();
+  void SendEmptyArray() override;
+
+  // TODO: Remove
+  void SendMGetResponse(SinkReplyBuilder::MGetResponse resp) override;
 
   static std::string SerializeCommmand(std::string_view cmd);
 };

src/facade/reply_builder_test.cc

@@ -205,7 +205,7 @@ RedisReplyBuilderTest::ParsingResults RedisReplyBuilderTest::Parse() {
 
 TEST_F(RedisReplyBuilderTest, MessageSend) {
   // Test each message that is "sent" to the sink
-  builder_->SendOk();
+  builder_->SinkReplyBuilder2::SendOk();
   ASSERT_EQ(TakePayload(), kOKMessage);
   builder_->StartArray(10);
 

src/facade/reply_capture.cc

@@ -3,6 +3,7 @@
 //
 #include "facade/reply_capture.h"
 
+#include "absl/types/span.h"
 #include "base/logging.h"
 #include "reply_capture.h"
 
@@ -81,10 +82,11 @@ void CapturingReplyBuilder::SendBulkString(std::string_view str) {
   Capture(BulkString{string{str}});
 }
 
-void CapturingReplyBuilder::SendScoredArray(const std::vector<std::pair<std::string, double>>& arr,
+void CapturingReplyBuilder::SendScoredArray(absl::Span<const std::pair<std::string, double>> arr,
                                             bool with_scores) {
   SKIP_LESS(ReplyMode::FULL);
-  Capture(ScoredArray{arr, with_scores});
+  std::vector<std::pair<std::string, double>> values(arr.begin(), arr.end());
+  Capture(ScoredArray{std::move(values), with_scores});
 }
 
 void CapturingReplyBuilder::StartCollection(unsigned len, CollectionType type) {
@@ -219,7 +221,8 @@ void CapturingReplyBuilder::SetReplyMode(ReplyMode mode) {
   current_ = monostate{};
 }
 
-optional<CapturingReplyBuilder::ErrorRef> CapturingReplyBuilder::GetError(const Payload& pl) {
+optional<CapturingReplyBuilder::ErrorRef> CapturingReplyBuilder::TryExtractError(
+    const Payload& pl) {
   if (auto* err = get_if<Error>(&pl); err != nullptr) {
     return ErrorRef{err->first, err->second};
   }

src/facade/reply_capture.h

@@ -42,7 +42,7 @@ class CapturingReplyBuilder : public RedisReplyBuilder {
   void SendSimpleString(std::string_view str) override;
 
   void SendBulkString(std::string_view str) override;
-  void SendScoredArray(const std::vector<std::pair<std::string, double>>& arr,
+  void SendScoredArray(absl::Span<const std::pair<std::string, double>> arr,
                        bool with_scores) override;
 
   void StartCollection(unsigned len, CollectionType type) override;
@@ -87,7 +87,7 @@ class CapturingReplyBuilder : public RedisReplyBuilder {
   static void Apply(Payload&& pl, RedisReplyBuilder* builder);
 
   // If an error is stored inside payload, get a reference to it.
-  static std::optional<ErrorRef> GetError(const Payload& pl);
+  static std::optional<ErrorRef> TryExtractError(const Payload& pl);
 
   struct CollectionPayload {
     CollectionPayload(unsigned len, CollectionType type);

src/server/main_service.cc

@@ -297,7 +297,7 @@ class InterpreterReplier : public RedisReplyBuilder {
   void SendBulkString(std::string_view str) final;
 
   void StartCollection(unsigned len, CollectionType type) final;
-  void SendScoredArray(const std::vector<std::pair<std::string, double>>& arr,
+  void SendScoredArray(absl::Span<const std::pair<std::string, double>> arr,
                        bool with_scores) final;
 
  private:
@@ -472,7 +472,7 @@ void InterpreterReplier::StartCollection(unsigned len, CollectionType) {
   }
 }
 
-void InterpreterReplier::SendScoredArray(const std::vector<std::pair<std::string, double>>& arr,
+void InterpreterReplier::SendScoredArray(absl::Span<const std::pair<std::string, double>> arr,
                                          bool with_scores) {
   if (with_scores) {
     if (IsResp3()) {
@@ -1727,7 +1727,7 @@ optional<CapturingReplyBuilder::Payload> Service::FlushEvalAsyncCmds(ConnectionC
   info->async_cmds.clear();
 
   auto reply = crb.Take();
-  return CapturingReplyBuilder::GetError(reply) ? make_optional(std::move(reply)) : nullopt;
+  return CapturingReplyBuilder::TryExtractError(reply) ? make_optional(std::move(reply)) : nullopt;
 }
 
 void Service::CallFromScript(ConnectionContext* cntx, Interpreter::CallArgs& ca) {
@@ -2030,7 +2030,7 @@ void Service::EvalInternal(CmdArgList args, const EvalArgs& eval_args, Interpret
     result = interpreter->RunFunction(eval_args.sha, &error);
 
     if (auto err = FlushEvalAsyncCmds(cntx, true); err) {
-      auto err_ref = CapturingReplyBuilder::GetError(*err);
+      auto err_ref = CapturingReplyBuilder::TryExtractError(*err);
       result = Interpreter::RUN_ERR;
       error = absl::StrCat(err_ref->first);
     }

src/server/multi_command_squasher.cc

@@ -239,7 +239,7 @@ bool MultiCommandSquasher::ExecuteSquashed() {
     auto& replies = sharded_[idx].replies;
     CHECK(!replies.empty());
 
-    aborted |= error_abort_ && CapturingReplyBuilder::GetError(replies.back());
+    aborted |= error_abort_ && CapturingReplyBuilder::TryExtractError(replies.back());
 
     CapturingReplyBuilder::Apply(std::move(replies.back()), rb);
     replies.pop_back();

src/server/rdb_load.cc

@@ -2606,7 +2606,7 @@ void RdbLoader::LoadSearchIndexDefFromAux(string&& def) {
   service_->DispatchCommand(absl::MakeSpan(arg_vec), &cntx);
 
   auto response = crb.Take();
-  if (auto err = facade::CapturingReplyBuilder::GetError(response); err) {
+  if (auto err = facade::CapturingReplyBuilder::TryExtractError(response); err) {
     LOG(ERROR) << "Bad index definition: " << def << " " << err->first;
   }
 }

tests/dragonfly/instance.py

@@ -87,9 +87,6 @@ class DflyInstance:
             if threads > 1:
                 self.args["num_shards"] = threads - 1
 
-        # Add 1 byte limit for big values
-        self.args["serialization_max_chunk_size"] = 1
-
     def __del__(self):
         assert self.proc == None
 
@@ -326,9 +323,6 @@ class DflyInstance:
         mem_info = process.memory_info()
         return mem_info.rss
 
-    def clear_max_chunk_flag(self):
-        del self.args["serialization_max_chunk_size"]
-
 
 class DflyInstanceFactory:
     """
@@ -340,7 +334,7 @@ class DflyInstanceFactory:
         self.params = params
         self.instances = []
 
-    def create(self, existing_port=None, path=None, **kwargs) -> DflyInstance:
+    def create(self, existing_port=None, path=None, version=100, **kwargs) -> DflyInstance:
         args = {**self.args, **kwargs}
         args.setdefault("dbfilename", "")
         args.setdefault("noversion_check", None)
@@ -351,6 +345,13 @@ class DflyInstanceFactory:
         args.setdefault("jsonpathv2")
         args.setdefault("log_dir", self.params.log_dir)
 
+        if version >= 1.21:
+            # Add 1 byte limit for big values
+            args.setdefault("serialization_max_chunk_size", 1)
+
+        if version >= 1.21:
+            args.setdefault("use_new_io")
+
         for k, v in args.items():
             args[k] = v.format(**self.params.env) if isinstance(v, str) else v
 

tests/dragonfly/replication_test.py

@@ -2386,8 +2386,7 @@ async def test_replicate_old_master(
 
     dfly_version = "v1.19.2"
     released_dfly_path = download_dragonfly_release(dfly_version)
-    master = df_factory.create(path=released_dfly_path, cluster_mode=cluster_mode)
+    master = df_factory.create(version=1.19, path=released_dfly_path, cluster_mode=cluster_mode)
-    master.clear_max_chunk_flag()
     replica = df_factory.create(
         cluster_mode=cluster_mode, announce_ip=announce_ip, announce_port=announce_port
     )