diff --git a/core/schemas/com.github.shadowsocks.database.PrivateDatabase/29.json b/core/schemas/com.github.shadowsocks.database.PrivateDatabase/29.json
index 5a695600e7..8251c64540 100644
--- a/core/schemas/com.github.shadowsocks.database.PrivateDatabase/29.json
+++ b/core/schemas/com.github.shadowsocks.database.PrivateDatabase/29.json
@@ -2,11 +2,11 @@
   "formatVersion": 1,
   "database": {
     "version": 29,
-    "identityHash": "5b5c55a1277c63e14416316f9198ed43",
+    "identityHash": "edf35c5851b4cb55bb5dbbf278199450",
     "entities": [
       {
         "tableName": "Profile",
-        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `name` TEXT, `host` TEXT NOT NULL, `remotePort` INTEGER NOT NULL, `password` TEXT NOT NULL, `method` TEXT NOT NULL, `route` TEXT NOT NULL, `remoteDns` TEXT NOT NULL, `proxyApps` INTEGER NOT NULL, `bypass` INTEGER NOT NULL, `udpdns` INTEGER NOT NULL, `ipv6` INTEGER NOT NULL, `metered` INTEGER NOT NULL, `individual` TEXT NOT NULL, `plugin` TEXT, `udpFallback` INTEGER, `subscription` INTEGER NOT NULL, `tx` INTEGER NOT NULL, `rx` INTEGER NOT NULL, `userOrder` INTEGER NOT NULL)",
+        "createSql": "CREATE TABLE IF NOT EXISTS `${TABLE_NAME}` (`id` INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, `name` TEXT, `host` TEXT NOT NULL, `remotePort` INTEGER NOT NULL, `password` TEXT NOT NULL, `method` TEXT NOT NULL, `route` TEXT NOT NULL, `remoteDns` TEXT NOT NULL, `proxyApps` INTEGER NOT NULL, `bypass` INTEGER NOT NULL, `udpdns` INTEGER NOT NULL, `ipv6` INTEGER NOT NULL, `metered` INTEGER NOT NULL, `individual` TEXT NOT NULL, `plugin` TEXT, `udpFallback` INTEGER, `optimizeBuffers` INTEGER NOT NULL, `subscription` INTEGER NOT NULL, `tx` INTEGER NOT NULL, `rx` INTEGER NOT NULL, `userOrder` INTEGER NOT NULL)",
         "fields": [
           {
             "fieldPath": "id",
@@ -104,6 +104,12 @@
             "affinity": "INTEGER",
             "notNull": false
           },
+          {
+            "fieldPath": "optimizeBuffers",
+            "columnName": "optimizeBuffers",
+            "affinity": "INTEGER",
+            "notNull": true
+          },
           {
             "fieldPath": "subscription",
             "columnName": "subscription",
@@ -130,10 +136,10 @@
           }
         ],
         "primaryKey": {
+          "autoGenerate": true,
           "columnNames": [
             "id"
-          ],
-          "autoGenerate": true
+          ]
         },
         "indices": [],
         "foreignKeys": []
@@ -162,10 +168,10 @@
           }
         ],
         "primaryKey": {
+          "autoGenerate": false,
           "columnNames": [
             "key"
-          ],
-          "autoGenerate": false
+          ]
         },
         "indices": [],
         "foreignKeys": []
@@ -174,7 +180,7 @@
     "views": [],
     "setupQueries": [
       "CREATE TABLE IF NOT EXISTS room_master_table (id INTEGER PRIMARY KEY,identity_hash TEXT)",
-      "INSERT OR REPLACE INTO room_master_table (id,identity_hash) VALUES(42, '5b5c55a1277c63e14416316f9198ed43')"
+      "INSERT OR REPLACE INTO room_master_table (id,identity_hash) VALUES(42, 'edf35c5851b4cb55bb5dbbf278199450')"
     ]
   }
 }
\ No newline at end of file
diff --git a/core/src/main/java/com/github/shadowsocks/bg/ProxyInstance.kt b/core/src/main/java/com/github/shadowsocks/bg/ProxyInstance.kt
index 05f834707b..41dcdaaea3 100644
--- a/core/src/main/java/com/github/shadowsocks/bg/ProxyInstance.kt
+++ b/core/src/main/java/com/github/shadowsocks/bg/ProxyInstance.kt
@@ -117,10 +117,22 @@ class ProxyInstance(val profile: Profile, private val route: String = profile.ro
         val cmd = arrayListOf(
                 File((service as Context).applicationInfo.nativeLibraryDir, Executable.SS_LOCAL).absolutePath,
                 "--stat-path", stat.absolutePath,
-                "-c", configFile.absolutePath,
+                "-c", configFile.absolutePath
         )
 
-        if (service.isVpnService) cmd += "--vpn"
+        if (profile.optimizeBuffers) {
+            cmd += "--inbound-send-buffer-size=16384"
+            cmd += "--inbound-recv-buffer-size=16384"
+
+            if (profile.plugin?.isNotBlank() == true) {
+                cmd += "--outbound-send-buffer-size=16384"
+                cmd += "--outbound-recv-buffer-size=16384"
+            }
+        }
+
+        if (service.isVpnService) {
+            cmd += "--vpn"
+        }
 
         if (route != Acl.ALL) {
             cmd += "--acl"
diff --git a/core/src/main/java/com/github/shadowsocks/database/Profile.kt b/core/src/main/java/com/github/shadowsocks/database/Profile.kt
index bae60e1066..d1f95a1836 100644
--- a/core/src/main/java/com/github/shadowsocks/database/Profile.kt
+++ b/core/src/main/java/com/github/shadowsocks/database/Profile.kt
@@ -70,6 +70,7 @@ data class Profile(
         var individual: String = "",
         var plugin: String? = null,
         var udpFallback: Long? = null,
+        var optimizeBuffers: Boolean = true,
 
         // managed fields
         var subscription: SubscriptionStatus = SubscriptionStatus.UserConfigured,
@@ -355,6 +356,7 @@ data class Profile(
         DataStore.individual = individual
         DataStore.plugin = plugin ?: ""
         DataStore.udpFallback = udpFallback
+        DataStore.optimizeBuffers = optimizeBuffers
         DataStore.privateStore.remove(Key.dirty)
     }
 
@@ -378,5 +380,6 @@ data class Profile(
         individual = DataStore.individual
         plugin = DataStore.plugin
         udpFallback = DataStore.udpFallback
+        optimizeBuffers = DataStore.optimizeBuffers
     }
 }
diff --git a/core/src/main/java/com/github/shadowsocks/preference/DataStore.kt b/core/src/main/java/com/github/shadowsocks/preference/DataStore.kt
index a523681f74..c6fd940c5c 100644
--- a/core/src/main/java/com/github/shadowsocks/preference/DataStore.kt
+++ b/core/src/main/java/com/github/shadowsocks/preference/DataStore.kt
@@ -104,6 +104,9 @@ object DataStore : OnPreferenceDataStoreChangeListener {
     var udpFallback: Long?
         get() = privateStore.getLong(Key.udpFallback)
         set(value) = privateStore.putLong(Key.udpFallback, value)
+    var optimizeBuffers: Boolean
+        get() = privateStore.getBoolean(Key.optimizeBuffers) ?: true
+        set(value) = privateStore.putBoolean(Key.optimizeBuffers, value)
     var dirty: Boolean
         get() = privateStore.getBoolean(Key.dirty) ?: false
         set(value) = privateStore.putBoolean(Key.dirty, value)
diff --git a/core/src/main/java/com/github/shadowsocks/utils/Constants.kt b/core/src/main/java/com/github/shadowsocks/utils/Constants.kt
index 52b6de20ec..b48f54bbd8 100644
--- a/core/src/main/java/com/github/shadowsocks/utils/Constants.kt
+++ b/core/src/main/java/com/github/shadowsocks/utils/Constants.kt
@@ -61,6 +61,7 @@ object Key {
     const val plugin = "plugin"
     const val pluginConfigure = "plugin.configure"
     const val udpFallback = "udpFallback"
+    const val optimizeBuffers = "optimizeBuffers";
 
     const val dirty = "profileDirty"
 
diff --git a/core/src/main/res/values/strings.xml b/core/src/main/res/values/strings.xml
index 04ed7d9d67..8fb5180a50 100644
--- a/core/src/main/res/values/strings.xml
+++ b/core/src/main/res/values/strings.xml
@@ -32,6 +32,8 @@
   <string name="remote_port">Remote Port</string>
   <string name="sitekey">Password</string>
   <string name="enc_method">Encrypt Method</string>
+  <string name="optimize_buffers">Optimize TCP Buffers</string>
+  <string name="optimize_buffers_summary">Fix upload timeout (bufferbloat)</string>
 
   <!-- feature category -->
   <string name="ipv6">IPv6 Route</string>
diff --git a/mobile/src/main/java/com/github/shadowsocks/ProfileConfigFragment.kt b/mobile/src/main/java/com/github/shadowsocks/ProfileConfigFragment.kt
index 8ca2d21c4d..f238097ec1 100644
--- a/mobile/src/main/java/com/github/shadowsocks/ProfileConfigFragment.kt
+++ b/mobile/src/main/java/com/github/shadowsocks/ProfileConfigFragment.kt
@@ -79,6 +79,7 @@ class ProfileConfigFragment : PreferenceFragmentCompat(),
     private lateinit var pluginConfiguration: PluginConfiguration
     private lateinit var receiver: BroadcastReceiver
     private lateinit var udpFallback: Preference
+    private lateinit var optimizeBuffers: SwitchPreference
 
     private fun makeDirt() {
         DataStore.dirty = true
@@ -115,6 +116,8 @@ class ProfileConfigFragment : PreferenceFragmentCompat(),
         pluginConfiguration = PluginConfiguration(DataStore.plugin)
         initPlugins()
         udpFallback = findPreference(Key.udpFallback)!!
+        optimizeBuffers = findPreference(Key.optimizeBuffers)!!
+        optimizeBuffers.isChecked = DataStore.optimizeBuffers
         DataStore.privateStore.registerChangeListener(this)
 
         val profile = ProfileManager.getProfile(profileId) ?: Profile()
diff --git a/mobile/src/main/res/xml/pref_profile.xml b/mobile/src/main/res/xml/pref_profile.xml
index 5db0dd19a3..64f2891d83 100644
--- a/mobile/src/main/res/xml/pref_profile.xml
+++ b/mobile/src/main/res/xml/pref_profile.xml
@@ -65,8 +65,11 @@
                 app:key="remoteDns"
                 app:icon="@drawable/ic_action_dns"
                 app:title="@string/remote_dns"
-                app:useSimpleSummaryProvider="true"/>
-
+                app:useSimpleSummaryProvider="true" />
+        <SwitchPreference
+                app:key="optimizeBuffers"
+                app:title="@string/optimize_buffers"
+                app:summary="@string/optimize_buffers_summary" />
     </PreferenceCategory>
 
     <PreferenceCategory