diff --git a/base/associative.jl b/base/associative.jl
index f46378b56d266..8c276ee8dc078 100644
--- a/base/associative.jl
+++ b/base/associative.jl
@@ -441,7 +441,12 @@ function delete!(t::ObjectIdDict, key::ANY)
     t
 end
 
-empty!(t::ObjectIdDict) = (t.ht = Vector{Any}(length(t.ht)); t.ndel = 0; t)
+function empty!(t::ObjectIdDict)
+    resize!(t.ht, 32)
+    ccall(:memset, Ptr{Void}, (Ptr{Void}, Cint, Csize_t), t.ht, 0, sizeof(t.ht))
+    t.ndel = 0
+    return t
+end
 
 _oidd_nextind(a, i) = reinterpret(Int,ccall(:jl_eqtable_nextind, Csize_t, (Any, Csize_t), a, i))
 
diff --git a/base/distributed/Distributed.jl b/base/distributed/Distributed.jl
index 36e4bcba53fc9..73270b0672b3b 100644
--- a/base/distributed/Distributed.jl
+++ b/base/distributed/Distributed.jl
@@ -10,7 +10,7 @@ import Base: getindex, wait, put!, take!, fetch, isready, push!, length,
 using Base: Process, Semaphore, JLOptions, AnyDict, buffer_writes, wait_connected,
             VERSION_STRING, sync_begin, sync_add, sync_end, async_run_thunk,
             binding_module, notify_error, atexit, julia_exename, julia_cmd,
-            AsyncGenerator, display_error, acquire, release
+            AsyncGenerator, display_error, acquire, release, invokelatest
 
 # NOTE: clusterserialize.jl imports additional symbols from Base.Serializer for use
 
diff --git a/base/distributed/messages.jl b/base/distributed/messages.jl
index aee31cec8bf50..17a447a154d1f 100644
--- a/base/distributed/messages.jl
+++ b/base/distributed/messages.jl
@@ -2,10 +2,8 @@
 
 abstract type AbstractMsg end
 
-let REF_ID::Int = 1
-    global next_ref_id
-    next_ref_id() = (id = REF_ID; REF_ID += 1; id)
-end
+const REF_ID = Ref(1)
+next_ref_id() = (id = REF_ID[]; REF_ID[] = id+1; id)
 
 struct RRID
     whence::Int
@@ -80,34 +78,32 @@ end
 # of approximately 10%. Can be removed once module Serializer
 # has been suitably improved.
 
-# replace  CallMsg{Mode} with specific invocations
-const msgtypes = filter!(x->x!=CallMsg, subtypes(AbstractMsg))
-push!(msgtypes, CallMsg{:call}, CallMsg{:call_fetch})
+const msgtypes = Any[CallWaitMsg, IdentifySocketAckMsg, IdentifySocketMsg,
+                     JoinCompleteMsg, JoinPGRPMsg, RemoteDoMsg, ResultMsg,
+                     CallMsg{:call}, CallMsg{:call_fetch}]
 
 for (idx, tname) in enumerate(msgtypes)
-    nflds = length(fieldnames(tname))
-    @eval begin
-        function serialize(s::AbstractSerializer, o::$tname)
-            write(s.io, UInt8($idx))
-            for fld in fieldnames($tname)
-                serialize(s, getfield(o, fld))
-            end
-        end
-
-        function deserialize_msg(s::AbstractSerializer, ::Type{$tname})
-            data=Array{Any,1}($nflds)
-            for i in 1:$nflds
-                data[i] = deserialize(s)
-            end
-            return $tname(data...)
-        end
+    exprs = Any[ :(serialize(s, o.$fld)) for fld in fieldnames(tname) ]
+    @eval function serialize_msg(s::AbstractSerializer, o::$tname)
+        write(s.io, UInt8($idx))
+        $(exprs...)
+        return nothing
     end
 end
 
-function deserialize_msg(s::AbstractSerializer)
-    idx = read(s.io, UInt8)
-    t = msgtypes[idx]
-    return eval(current_module(), Expr(:body, Expr(:return, Expr(:call, deserialize_msg, QuoteNode(s), QuoteNode(t)))))
+let msg_cases = :(assert(false))
+    for i = length(msgtypes):-1:1
+        mti = msgtypes[i]
+        msg_cases = :(if idx == $i
+                          return $(Expr(:call, QuoteNode(mti), fill(:(deserialize(s)), nfields(mti))...))
+                      else
+                          $msg_cases
+                      end)
+    end
+    @eval function deserialize_msg(s::AbstractSerializer)
+        idx = read(s.io, UInt8)
+        $msg_cases
+    end
 end
 
 function send_msg_unknown(s::IO, header, msg)
@@ -171,8 +167,7 @@ function serialize_hdr_raw(io, hdr)
 end
 
 function deserialize_hdr_raw(io)
-    data = Array{Int,1}(4)
-    read!(io, data)
+    data = read(io, Ref{NTuple{4,Int}}())[]
     return MsgHeader(RRID(data[1], data[2]), RRID(data[3], data[4]))
 end
 
@@ -183,7 +178,7 @@ function send_msg_(w::Worker, header, msg, now::Bool)
     try
         reset_state(w.w_serializer)
         serialize_hdr_raw(io, header)
-        eval(current_module(), Expr(:body, Expr(:return, Expr(:call, serialize, QuoteNode(w.w_serializer), QuoteNode(msg)))))  # io is wrapped in w_serializer
+        invokelatest(serialize_msg, w.w_serializer, msg)  # io is wrapped in w_serializer
         write(io, MSG_BOUNDARY)
 
         if !now && w.gcflag
diff --git a/base/distributed/process_messages.jl b/base/distributed/process_messages.jl
index 121467676a64f..1eba6eafd496d 100644
--- a/base/distributed/process_messages.jl
+++ b/base/distributed/process_messages.jl
@@ -158,7 +158,7 @@ function message_handler_loop(r_stream::IO, w_stream::IO, incoming::Bool)
             # println("header: ", header)
 
             try
-                msg = deserialize_msg(serializer)
+                msg = invokelatest(deserialize_msg, serializer)
             catch e
                 # Deserialization error; discard bytes in stream until boundary found
                 boundary_idx = 1
diff --git a/base/distributed/remotecall.jl b/base/distributed/remotecall.jl
index 67d4476d0cc18..e03f1d19a8d9d 100644
--- a/base/distributed/remotecall.jl
+++ b/base/distributed/remotecall.jl
@@ -152,7 +152,7 @@ function lookup_ref(pg, rrid, f)
         rv = get(pg.refs, rrid, false)
         if rv === false
             # first we've heard of this ref
-            rv = RemoteValue(eval(Main, Expr(:body, Expr(:return, Expr(:call, f)))))
+            rv = RemoteValue(invokelatest(f))
             pg.refs[rrid] = rv
             push!(rv.clientset, rrid.whence)
         end
diff --git a/base/precompile.jl b/base/precompile.jl
index 2342279959196..8bc84db37f499 100644
--- a/base/precompile.jl
+++ b/base/precompile.jl
@@ -1405,7 +1405,6 @@ precompile(Tuple{typeof(Base.close), Base.TCPSocket})
 precompile(Tuple{typeof(Base.write), Base.TCPSocket, Array{UInt8, 1}})
 precompile(Tuple{typeof(Base.wait_readnb), Base.PipeEndpoint, Int64})
 precompile(Tuple{typeof(Base.eof), Base.PipeEndpoint})
-precompile(Tuple{typeof(Base.Distributed.deserialize_msg), Base.Distributed.ClusterSerializer{Base.TCPSocket}, Type{Base.Distributed.JoinPGRPMsg}})
 precompile(Tuple{typeof(Base.unsafe_read), Base.TCPSocket, Base.RefValue{Int32}, Int64})
 precompile(Tuple{typeof(Base.unsafe_read), Base.TCPSocket, Base.RefValue{Int64}, Int64})
 precompile(Tuple{typeof(Base.read!), Base.TCPSocket, Array{UInt8, 1}})
@@ -1479,7 +1478,6 @@ precompile(Tuple{typeof(Base.notify), Base.Condition, Base.Distributed.ProcessEx
 precompile(Tuple{typeof(Base.pop!), Base.Dict{Int64, Union{Base.Distributed.Worker, Base.Distributed.LocalProcess}}, Int64, Void})
 precompile(Tuple{typeof(Base.Distributed.deregister_worker), Base.Distributed.ProcessGroup, Int64})
 precompile(Tuple{typeof(Base.Distributed.process_hdr), Base.TCPSocket, Bool})
-precompile(Tuple{typeof(Base.Distributed.deserialize_msg), Base.Distributed.ClusterSerializer{Base.TCPSocket}})
 precompile(Tuple{typeof(Base.Distributed.null_id), Base.Distributed.RRID})
 precompile(Tuple{typeof(Base.Distributed.deliver_result), Base.TCPSocket, Symbol, Base.Distributed.RRID, Base.Distributed.RemoteException})
 precompile(Tuple{typeof(Base.Distributed.disable_nagle), Base.TCPSocket})
@@ -1535,7 +1533,6 @@ precompile(Tuple{typeof(Base.Serializer.serialize), Base.Distributed.ClusterSeri
 precompile(Tuple{typeof(Base.unsafe_write), Base.TCPSocket, Base.RefValue{UInt8}, Int64})
 precompile(Tuple{typeof(Base.Serializer.serialize), Base.Distributed.ClusterSerializer{Base.TCPSocket}, Int64})
 precompile(Tuple{typeof(Base.write), Base.TCPSocket, Array{UInt8, 1}})
-precompile(Tuple{typeof(Base.Distributed.deserialize_msg), Base.Distributed.ClusterSerializer{Base.TCPSocket}, Type{Base.Distributed.JoinCompleteMsg}})
 precompile(Tuple{typeof(Base.unsafe_read), Base.TCPSocket, Base.RefValue{Int32}, Int64})
 precompile(Tuple{typeof(Base.unsafe_read), Base.TCPSocket, Base.RefValue{Int64}, Int64})
 precompile(Tuple{typeof(Base.read!), Base.TCPSocket, Array{UInt8, 1}})
diff --git a/base/serialize.jl b/base/serialize.jl
index 55df21d7c201e..4b309489226c9 100644
--- a/base/serialize.jl
+++ b/base/serialize.jl
@@ -157,7 +157,7 @@ end
 
 function reset_state(s::AbstractSerializer)
     s.counter = 0
-    s.table = ObjectIdDict()
+    empty!(s.table)
     empty!(s.pending_refs)
     s
 end
diff --git a/base/stream.jl b/base/stream.jl
index 4c0d931e72282..4bd1f4c070d88 100644
--- a/base/stream.jl
+++ b/base/stream.jl
@@ -863,7 +863,15 @@ buffer_writes(s::LibuvStream, bufsize) = (s.sendbuf=PipeBuffer(bufsize); s)
 
 ## low-level calls to libuv ##
 
-write(s::LibuvStream, b::UInt8) = write(s, Ref{UInt8}(b))
+function write(s::LibuvStream, b::UInt8)
+    if !isnull(s.sendbuf)
+        buf = get(s.sendbuf)
+        if nb_available(buf) + 1 < buf.maxsize
+            return write(buf, b)
+        end
+    end
+    return write(s, Ref{UInt8}(b))
+end
 
 function uv_writecb_task(req::Ptr{Void}, status::Cint)
     d = uv_req_data(req)