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diff --git a/weed/mq/README.md b/weed/mq/README.md
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+# SeaweedMQ Message Queue on SeaweedFS (WIP, not ready)
+
+## What are the use cases it is designed for?
+
+Message queues are like water pipes. Messages flow in the pipes to their destinations.
+
+However, what if a flood comes? Of course, you can increase the number of partitions, add more brokers, restart, 
+and watch the traffic level closely.
+
+Sometimes the flood is expected. For example, backfill some old data in batch, and switch to online messages. 
+You may want to ensure enough brokers to handle the data and reduce them later to cut cost.
+
+SeaweedMQ is designed for use cases that need to:
+* Receive and save large number of messages.
+* Handle spike traffic automatically.
+
+## What is special about SeaweedMQ?
+
+* Separate computation and storage nodes that scales independently.
+  * Offline messages can be operated as normal files.
+  * Unlimited storage space by adding volume servers.
+  * Unlimited message brokers.
+* Scale up and down with auto split and merge message topics.
+  * Topics can automatically split into segments when traffic increases, and vice verse.
+  * 
+
+# Design
+
+# How it works?
+
+Brokers are just computation nodes without storage. When a broker starts, it reports itself to masters.
+Among all the brokers, one of them will be selected as the leader by the masters.
+
+A topic needs to define its partition key on its messages.
+
+Messages for a topic are divided into segments. 
+
+During write time, the client will ask the broker leader for a few brokers to process the segment.
+
+The broker leader will check whether the segment already has assigned the brokers. If not, select a few based
+on their loads, save the selection into filer, and tell the client.
+
+The client will write the messages for this segment to the selected brokers.
+
+## Failover
+
+The broker leader does not contain any state. If it fails, the masters will select a different broker.
+
+For a segment, if any one of the selected brokers is down, the remaining brokers should try to write received messages
+to the filer, and close the segment to the clients.
+
+Then the clients should start a new segment. The masters should other healthy brokers to handle the new segment.
+
+So any brokers can go down without losing data.
+
+## Auto Split or Merge
+
+(The idea is learned from Pravega.)
+
+The brokers should report its traffic load to the broker leader periodically.
+
+If any segment has too much load, the broker leader will ask the brokers to tell the client to 
+close current one and create two new segments.
+
+If 2 neighboring segments have the combined load below average load per segment, the broker leader will ask 
+the brokers to tell the client to close this 2 segments and create a new segment.
diff --git a/weed/mq/segment/message_serde.go b/weed/mq/segment/message_serde.go
new file mode 100644
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+++ b/weed/mq/segment/message_serde.go
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+package segment
+
+import (
+	"github.com/chrislusf/seaweedfs/weed/pb/message_fbs"
+	flatbuffers "github.com/google/flatbuffers/go"
+)
+
+func CreateMessage(b *flatbuffers.Builder, producerId int32, producerSeq int64, segmentId int32, segmentSeq int64,
+	eventTsNs int64, recvTsNs int64, properties map[string]string, key []byte, value []byte) {
+	b.Reset()
+
+	var names, values, pairs []flatbuffers.UOffsetT
+	for k, v := range properties {
+		names = append(names, b.CreateString(k))
+		values = append(values, b.CreateString(v))
+	}
+
+	for i, _ := range names {
+		message_fbs.NameValueStart(b)
+		message_fbs.NameValueAddName(b, names[i])
+		message_fbs.NameValueAddValue(b, values[i])
+		pair := message_fbs.NameValueEnd(b)
+		pairs = append(pairs, pair)
+	}
+	message_fbs.MessageStartPropertiesVector(b, len(properties))
+	for i := len(pairs) - 1; i >= 0; i-- {
+		b.PrependUOffsetT(pairs[i])
+	}
+	prop := b.EndVector(len(properties))
+
+	k := b.CreateByteVector(key)
+	v := b.CreateByteVector(value)
+
+	message_fbs.MessageStart(b)
+	message_fbs.MessageAddProducerId(b, producerId)
+	message_fbs.MessageAddProducerSeq(b, producerSeq)
+	message_fbs.MessageAddSegmentId(b, segmentId)
+	message_fbs.MessageAddSegmentSeq(b, segmentSeq)
+	message_fbs.MessageAddEventTsNs(b, eventTsNs)
+	message_fbs.MessageAddRecvTsNs(b, recvTsNs)
+
+	message_fbs.MessageAddProperties(b, prop)
+	message_fbs.MessageAddKey(b, k)
+	message_fbs.MessageAddData(b, v)
+	message := message_fbs.MessageEnd(b)
+
+	b.Finish(message)
+}
diff --git a/weed/mq/segment/message_serde_test.go b/weed/mq/segment/message_serde_test.go
new file mode 100644
index 000000000..7ba0febf0
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+++ b/weed/mq/segment/message_serde_test.go
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+package segment
+
+import (
+	"github.com/chrislusf/seaweedfs/weed/pb/message_fbs"
+	flatbuffers "github.com/google/flatbuffers/go"
+	"github.com/stretchr/testify/assert"
+	"testing"
+)
+
+func TestMessageSerde(t *testing.T) {
+	b := flatbuffers.NewBuilder(1024)
+
+	prop := make(map[string]string)
+	prop["n1"] = "v1"
+	prop["n2"] = "v2"
+
+	CreateMessage(b, 1, 2, 3, 4, 5, 6, prop,
+		[]byte("the primary key"), []byte("body is here"))
+
+	buf := b.FinishedBytes()
+
+	println("serialized size", len(buf))
+
+	m := message_fbs.GetRootAsMessage(buf, 0)
+
+	assert.Equal(t, int32(1), m.ProducerId())
+	assert.Equal(t, int64(2), m.ProducerSeq())
+	assert.Equal(t, int32(3), m.SegmentId())
+	assert.Equal(t, int64(4), m.SegmentSeq())
+	assert.Equal(t, int64(5), m.EventTsNs())
+	assert.Equal(t, int64(6), m.RecvTsNs())
+
+	assert.Equal(t, 2, m.PropertiesLength())
+	nv := &message_fbs.NameValue{}
+	m.Properties(nv, 0)
+	assert.Equal(t, "n1", string(nv.Name()))
+	assert.Equal(t, "v1", string(nv.Value()))
+	m.Properties(nv, 1)
+	assert.Equal(t, "n2", string(nv.Name()))
+	assert.Equal(t, "v2", string(nv.Value()))
+	assert.Equal(t, []byte("the primary key"), m.Key())
+	assert.Equal(t, []byte("body is here"), m.Data())
+
+	m.MutateSegmentSeq(123)
+	assert.Equal(t, int64(123), m.SegmentSeq())
+
+}
diff --git a/weed/mq/segment/segment_serde.go b/weed/mq/segment/segment_serde.go
new file mode 100644
index 000000000..e076271d6
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+++ b/weed/mq/segment/segment_serde.go
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+package segment