add compression for log

config/config.go

@@ -34,6 +34,7 @@ type ReplicationConfig struct {
 	ExpiredLogDays int    `toml:"expired_log_days"`
 	Sync           bool   `toml:"sync"`
 	WaitSyncTime   int    `toml:"wait_sync_time"`
+	Compression    bool   `toml:"compression"`
 }
 
 type Config struct {
@@ -98,6 +99,7 @@ func NewConfigDefault() *Config {
 	cfg.LMDB.NoSync = true
 
 	cfg.Replication.WaitSyncTime = 1
+	cfg.Replication.Compression = true
 
 	return cfg
 }

config/config.toml

@@ -54,9 +54,11 @@ path = ""
 expired_log_days = 7
 
 # If sync is true, the new log must be sent to some slaves, and then commit. 
-# It may affect performance. 
+# It will reduce performance but have better high availability. 
 sync = true
 
-# If sync is true, wait at last wait_sync_time seconds to check whether slave sync this log
+# If sync is true, wait at last wait_sync_time seconds for slave syncing this log
 wait_sync_time = 1
 
+# Compress the log or not
+compression = true