diff --git a/.gitignore b/.gitignore
index 94a8c105..517cce2b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -37,8 +37,12 @@ recommonmark
 recom
 _*
 
+#mpi lib
+mpich/
+mpich-3.2/
+
 # Jetbrain
 .idea
 cmake-build-debug/
-
+.vscode/
 
diff --git a/.travis.yml b/.travis.yml
index ba01f423..a2eff4dc 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,12 @@
-# disable sudo to use container based build
-sudo: false
+sudo: true
+
+os:
+  - linux
+  - osx
+
+osx_image: xcode10.2
+
+dist: xenial
 
 # Use Build Matrix to do lint and build seperately
 env:
@@ -10,15 +17,17 @@ env:
     - TASK=build
     - TASK=mpi-build
     - TASK=cmake-build
-    - TASK=test CXX=g++-4.8
+    - TASK=test CXX=g++
 
 # dependent apt packages
-dist: xenial
 addons:
   apt:
+    sources:
+      - llvm-toolchain-trusty-5.0
+      - ubuntu-toolchain-r-test
+      - george-edison55-precise-backports
     packages:
       - doxygen
-      - libopenmpi-dev
       - wget
       - git
       - libcurl4-openssl-dev
@@ -26,30 +35,43 @@ addons:
       - python-numpy
       - gcc-4.8
       - g++-4.8
-      - openmpi-bin
-      - openmpi-common
       - openssh-client
       - openssh-server
-      - libopenmpi-dev
+      - python3
+      - python3-setuptools
+  homebrew:
+    packages:
+      - gcc49
+      - openssl
+      - libgit2
+      - python3
+    update: true
       
 before_install:
   - export TRAVIS=dmlc-core/scripts/travis/
   - source ${TRAVIS}/travis_setup_env.sh
+  - ${TRAVIS}/travis_osx_install.sh
 
 install:
-  - pip install --user cpplint pylint kubernetes urllib3
+  - if [[ ${TRAVIS_OS_NAME} == "linux" ]]; then sudo apt-get install python3-pip; fi
+  - if [[ ${TRAVIS_OS_NAME} == "osx" ]]; then brew install python3; fi
+  - pip3 install cpplint pylint urllib3 numpy
+  - pip3 install websocket-client kubernetes
 
 script: scripts/travis_script.sh
 
-
-before_cache:
-  - ${TRAVIS}/travis_before_cache.sh
-
-
 cache:
   directories:
     - ${HOME}/.cache/usr
+    - ${HOME}/.cache/pip
+    - mpich
 
+before_cache:
+  - ${TRAVIS}/travis_before_cache.sh
+
+after_success:
+  - tree build
+  - bash <(curl -s https://codecov.io/bash) -a '-o src/ src/*.c'
 
 notifications:
 # Emails are sent to the committer's git-configured email address by default,
@@ -57,4 +79,3 @@ notifications:
     on_success: change
     on_failure: always
 
-
diff --git a/Makefile b/Makefile
index 2af5b9b2..5599d4f3 100644
--- a/Makefile
+++ b/Makefile
@@ -1,23 +1,26 @@
 OS := $(shell uname)
 
-export MPICXX = mpicxx
-export LDFLAGS=  -Llib
+export WARNFLAGS= -Wall -Wextra -Wno-unused-parameter -Wno-unknown-pragmas -std=c++11
+export CFLAGS = -O3 $(WARNFLAGS) -I $(DMLC)/include -I include/
+export LDFLAGS =-Llib
 
-OS := $(shell uname)
+#download mpi
+#echo $(shell scripts/mpi.sh)
+
+MPICXX=./mpich/bin/mpicxx
 
 ifeq ($(OS), Darwin)
     ifndef CC
-        export CC = $(if $(shell which clang), clang, gcc)
+        export CC = gcc-4.9
     endif
     ifndef CXX
-        export CXX = $(if $(shell which clang++), clang++, g++)
+        export CXX = g++-4.9
     endif
 else
     ifeq ($(OS), FreeBSD)
          ifndef CXX
              export CXX = g++6
          endif
-         export MPICXX = /usr/local/mpi/bin/mpicxx
          export LDFLAGS= -Llib -Wl,-rpath=/usr/local/lib/gcc6
     else
         # linux defaults
@@ -27,13 +30,10 @@ else
         ifndef CXX
             export CXX = g++
         endif
-        LDFLAGS += -lrt
+        LDFLAGS +=-lrt
     endif
 endif
 
-export WARNFLAGS= -Wall -Wextra -Wno-unused-parameter -Wno-unknown-pragmas -std=c++11
-export CFLAGS = -O3 $(WARNFLAGS)
-
 #----------------------------
 # Settings for power and arm arch
 #----------------------------
@@ -69,8 +69,10 @@ BPATH=.
 MPIOBJ= $(BPATH)/engine_mpi.o
 OBJ= $(BPATH)/allreduce_base.o $(BPATH)/allreduce_robust.o $(BPATH)/engine.o $(BPATH)/engine_empty.o $(BPATH)/engine_mock.o\
 	$(BPATH)/c_api.o $(BPATH)/engine_base.o
-SLIB= lib/librabit.so lib/librabit_mpi.so lib/librabit_mock.so lib/librabit_base.so
-ALIB= lib/librabit.a lib/librabit_mpi.a lib/librabit_empty.a lib/librabit_mock.a lib/librabit_base.a
+SLIB= lib/librabit.so lib/librabit_mock.so lib/librabit_base.so
+ALIB= lib/librabit.a lib/librabit_empty.a lib/librabit_mock.a lib/librabit_base.a
+MPISLIB= lib/librabit_mpi.so
+MPIALIB= lib/librabit_mpi.a
 HEADERS=src/*.h include/rabit/*.h include/rabit/internal/*.h
 DMLC=dmlc-core
 
@@ -95,10 +97,7 @@ lib/librabit_empty.a: $(BPATH)/engine_empty.o $(BPATH)/c_api.o
 lib/librabit_mpi.a lib/librabit_mpi.so: $(MPIOBJ)
 
 $(OBJ) :
-	$(CXX) -c $(CFLAGS) -o $@ $(firstword $(filter %.cpp %.c %.cc, $^) ) -I include/ -I $(DMLC)/include
-
-$(MPIOBJ) :
-	$(MPICXX) -c $(CFLAGS) -o $@ $(firstword $(filter %.cpp %.c %.cc, $^) ) -I $(DMLC)/include
+	$(CXX) -c $(CFLAGS) -o $@ $(firstword $(filter %.cpp %.c %.cc, $^) )
 
 $(ALIB):
 	ar cr $@ $+
@@ -106,6 +105,16 @@ $(ALIB):
 $(SLIB) :
 	$(CXX) $(CFLAGS) -shared -o $@ $(filter %.cpp %.o %.c %.cc %.a, $^) $(LDFLAGS)
 
+$(MPIOBJ) :
+	$(MPICXX) -c $(CFLAGS) -I./mpich/include -o $@ $(firstword $(filter %.cpp %.c %.cc, $^) )
+
+$(MPIALIB):
+	ar cr $@ $+
+
+$(MPISLIB) :
+	$(MPICXX) $(CFLAGS) -I./mpich/include -shared -o $@ $(filter %.cpp %.o %.c %.cc %.a, $^) \
+	$(LDFLAGS) -L./mpich/lib -Wl,-rpath,./mpich/lib -lmpi
+
 lint:
 	$(DMLC)/scripts/lint.py rabit $(LINT_LANG) src include
 
@@ -113,4 +122,4 @@ doc doxygen:
 	cd include; doxygen ../doc/Doxyfile; cd -
 
 clean:
-	$(RM) $(OBJ) $(MPIOBJ) $(ALIB) $(MPIALIB) $(SLIB) *~ src/*~ include/*~ include/*/*~
+	$(RM)  $(OBJ) $(MPIOBJ) $(ALIB) $(MPIALIB) $(SLIB) *~ src/*~ include/*~ include/*/*~
diff --git a/dmlc-core b/dmlc-core
index 15362f8f..13d5acb8 160000
--- a/dmlc-core
+++ b/dmlc-core
@@ -1 +1 @@
-Subproject commit 15362f8fcc7345d60de13a676a2cbd3ffdc3f064
+Subproject commit 13d5acb8ba7e79550bbf2f730f1a3944ff0fa68b
diff --git a/python/rabit.py b/python/rabit.py
index d57587ba..dccb464c 100644
--- a/python/rabit.py
+++ b/python/rabit.py
@@ -4,7 +4,7 @@
 Author: Tianqi Chen
 """
 # pylint: disable=unused-argument,invalid-name,global-statement,dangerous-default-value,
-import cPickle as pickle
+import pickle
 import ctypes
 import os
 import sys
@@ -99,9 +99,10 @@ def init(args=None, lib='standard', lib_dll=None):
         When this is presented argument lib will be ignored.
     """
     if args is None:
-        args = sys.argv
+        args = []
     _loadlib(lib, lib_dll)
     arr = (ctypes.c_char_p * len(args))()
+
     arr[:] = args
     _LIB.RabitInit(len(args), arr)
 
diff --git a/scripts/mpi_build.sh b/scripts/mpi_build.sh
new file mode 100755
index 00000000..b1e70be9
--- /dev/null
+++ b/scripts/mpi_build.sh
@@ -0,0 +1,27 @@
+#!/usr/bin/env bash
+
+if [ -f mpich/lib/libmpich.so ]; then
+  echo "libmpich.so found -- nothing to build."
+else
+  echo "Downloading mpich source."
+  wget http://www.mpich.org/static/downloads/3.2/mpich-3.2.tar.gz
+  tar xfz mpich-3.2.tar.gz
+  rm mpich-3.2.tar.gz*
+  echo "configuring and building mpich."
+  cd mpich-3.2
+  #CC=gcc CXX=g++ CFLAGS=-m64 CXXFLAGS=-m64 FFLAGS=-m64
+  ./configure \
+          --prefix=`pwd`/../mpich \
+          --enable-static=false \
+          --enable-alloca=true \
+          --disable-long-double \
+          --enable-threads=single \
+          --enable-fortran=no \
+          --enable-fast=all \
+          --enable-g=none \
+          --enable-timing=none \
+          --enable-cxx
+  make -j4
+  make install
+  cd -
+fi
\ No newline at end of file
diff --git a/scripts/travis_runtest.sh b/scripts/travis_runtest.sh
index 4f14ad17..37fc9953 100755
--- a/scripts/travis_runtest.sh
+++ b/scripts/travis_runtest.sh
@@ -7,3 +7,4 @@ make -f test.mk local_recover_10_10k || exit -1
 make -f test.mk lazy_recover_10_10k_die_hard || exit -1
 make -f test.mk lazy_recover_10_10k_die_same || exit -1
 make -f test.mk ringallreduce_10_10k || exit -1
+make -f test.mk pylocal_recover_10_10k || exit -1
diff --git a/scripts/travis_script.sh b/scripts/travis_script.sh
index 12e78f65..ae150487 100755
--- a/scripts/travis_script.sh
+++ b/scripts/travis_script.sh
@@ -15,6 +15,7 @@ if [ ${TASK} == "build" ]; then
 fi
 
 if [ ${TASK} == "mpi-build" ]; then
+    ./scripts/mpi_build.sh
     cd test
     make mpi && make speed_test.mpi || exit -1
 fi
diff --git a/src/allreduce_base.cc b/src/allreduce_base.cc
index 143db6e1..60351699 100644
--- a/src/allreduce_base.cc
+++ b/src/allreduce_base.cc
@@ -131,6 +131,8 @@ void AllreduceBase::Shutdown(void) {
   utils::TCPSocket tracker = this->ConnectTracker();
   tracker.SendStr(std::string("shutdown"));
   tracker.Close();
+  // close listening sockets
+  sock_listen.Close();
   utils::TCPSocket::Finalize();
 }
 void AllreduceBase::TrackerPrint(const std::string &msg) {
@@ -271,12 +273,26 @@ void AllreduceBase::ReConnectLinks(const char *cmd) {
          "ReConnectLink failure 4");
   Assert(tracker.RecvAll(&next_rank, sizeof(next_rank)) == sizeof(next_rank),
          "ReConnectLink failure 4");
-  // create listening socket
-  utils::TCPSocket sock_listen;
-  sock_listen.Create();
-  int port = sock_listen.TryBindHost(slave_port, slave_port + nport_trial);
-  utils::Check(port != -1, "ReConnectLink fail to bind the ports specified");
-  sock_listen.Listen();
+
+  if (sock_listen == INVALID_SOCKET || sock_listen.AtMark()) {
+    if (!sock_listen.IsClosed()) {
+      sock_listen.Close();
+    }
+    // create listening socket
+    sock_listen.Create();
+    sock_listen.SetKeepAlive(true);
+    // http://deepix.github.io/2016/10/21/tcprst.html
+    sock_listen.SetLinger(0);
+    // [slave_port, slave_port+1 .... slave_port + newrank ...slave_port + nport_trial)
+    // work around processes bind to same port without set reuse option,
+    // start explore from slave_port + newrank towards end
+    port = sock_listen.TryBindHost(slave_port+ newrank%nport_trial, slave_port + nport_trial);
+    // if no port bindable, explore first half of range
+    if (port == -1) sock_listen.TryBindHost(slave_port, newrank% nport_trial + slave_port);
+
+    utils::Check(port != -1, "ReConnectLink fail to bind the ports specified");
+    sock_listen.Listen();
+  }
 
   // get number of to connect and number of to accept nodes from tracker
   int num_conn, num_accept, num_error = 1;
@@ -311,6 +327,7 @@ void AllreduceBase::ReConnectLinks(const char *cmd) {
              "ReConnectLink failure 9");
       Assert(tracker.RecvAll(&hrank, sizeof(hrank)) == sizeof(hrank),
              "ReConnectLink failure 10");
+
       r.sock.Create();
       if (!r.sock.Connect(utils::SockAddr(hname.c_str(), hport))) {
         num_error += 1; r.sock.Close(); continue;
@@ -357,8 +374,7 @@ void AllreduceBase::ReConnectLinks(const char *cmd) {
     }
     if (!match) all_links.push_back(r);
   }
-  // close listening sockets
-  sock_listen.Close();
+
   this->parent_index = -1;
   // setup tree links and ring structure
   tree_links.plinks.clear();
diff --git a/src/allreduce_base.h b/src/allreduce_base.h
index 02c76d6f..b83cb0d0 100644
--- a/src/allreduce_base.h
+++ b/src/allreduce_base.h
@@ -521,6 +521,10 @@ class AllreduceBase : public IEngine {
   int world_size;
   // connect retry time
   int connect_retry;
+  // backdoor listening peer connection
+  utils::TCPSocket sock_listen;
+  // backdoor port
+  int port = 0;
 };
 }  // namespace engine
 }  // namespace rabit
diff --git a/src/allreduce_robust.cc b/src/allreduce_robust.cc
index 43871e01..ce5a5616 100644
--- a/src/allreduce_robust.cc
+++ b/src/allreduce_robust.cc
@@ -51,12 +51,10 @@ void AllreduceRobust::Shutdown(void) {
   utils::Assert(RecoverExec(NULL, 0, ActionSummary::kCheckAck, ActionSummary::kSpecialOp),
                 "Shutdown: check ack must return true");
 
-  // one worker shutdowns and closes sockets while rest still run kCheckAck,
-  // seems has something to do with time-wait state in tcp connection,
-  // this cause rest workers checkandrecover and hang inf,
-  // https://github.com/dmlc/xgboost/pull/3818
-  // TODO(Chen Qin): a fundamental fix for this
-  sleep(1);
+#if defined (__APPLE__)
+        sleep(1);
+#endif
+
   AllreduceBase::Shutdown();
 }
 /*!
diff --git a/src/socket.h b/src/socket.h
index d127113a..d6e6f597 100644
--- a/src/socket.h
+++ b/src/socket.h
@@ -276,13 +276,21 @@ class TCPSocket : public Socket{
    * \brief enable/disable TCP keepalive
    * \param keepalive whether to set the keep alive option on
    */
-  inline void SetKeepAlive(bool keepalive) {
+  void SetKeepAlive(bool keepalive) {
     int opt = static_cast<int>(keepalive);
     if (setsockopt(sockfd, SOL_SOCKET, SO_KEEPALIVE,
                    reinterpret_cast<char*>(&opt), sizeof(opt)) < 0) {
       Socket::Error("SetKeepAlive");
     }
   }
+  inline void SetLinger(int timeout = 0) {
+    struct linger sl;
+    sl.l_onoff = 1;    /* non-zero value enables linger option in kernel */
+    sl.l_linger = timeout;    /* timeout interval in seconds */
+    if (setsockopt(sockfd, SOL_SOCKET, SO_LINGER, &sl, sizeof(sl)) == -1) {
+      Socket::Error("SO_LINGER");
+    }
+  }
   /*!
    * \brief create the socket, call this before using socket
    * \param af domain
diff --git a/test/Makefile b/test/Makefile
index 5a6ba2aa..b1c329d3 100644
--- a/test/Makefile
+++ b/test/Makefile
@@ -1,4 +1,4 @@
-export MPICXX = mpicxx
+MPICXX=../mpich/bin/mpicxx
 export LDFLAGS=  -L../lib -pthread -lm
 export CFLAGS = -Wall -O3 -msse2  -Wno-unknown-pragmas -fPIC -I../include -I ../dmlc-core/include -std=c++11
 
@@ -27,11 +27,17 @@ OBJ = $(RABIT_OBJ) speed_test.o model_recover.o local_recover.o lazy_recover.o
 MPIBIN = speed_test.mpi
 .PHONY: clean all lib mpi
 
+.PHONY: lib all
+
 all: $(BIN)
+
 lib:
-	cd ..;make;cd -
+	cd ..;make clean;make;cd -
+
+.PHONY: mpi
 mpi:
 	cd ..;make mpi;cd -
+
 # programs
 speed_test.o: speed_test.cc ../include/rabit/*.h lib mpi
 model_recover.o: model_recover.cc ../include/rabit/*.h lib
@@ -52,7 +58,8 @@ $(OBJ) :
 	$(CXX) -c $(CFLAGS) -o $@ $(firstword $(filter %.cpp %.c %.cc, $^) )
 
 $(MPIBIN) :
-	$(MPICXX) $(CFLAGS) -o $@ $(filter %.cpp %.o %.c %.cc, $^) ../lib/librabit_mpi.so $(LDFLAGS)
+	$(MPICXX) $(CFLAGS) -I../mpich/include -shared -o $@ $(filter %.cpp %.o %.c %.cc, $^) \
+    ../lib/librabit_mpi.so $(LDFLAGS) -L../mpich/lib -Wl,-rpath,../mpich/lib -lmpi
 
 clean:
 	$(RM) $(OBJ) $(BIN) $(MPIBIN) $(MPIOBJ) *~ ../src/*~
diff --git a/test/lazy_recover.cc b/test/lazy_recover.cc
index dd64294b..180e2e4b 100644
--- a/test/lazy_recover.cc
+++ b/test/lazy_recover.cc
@@ -118,7 +118,7 @@ int main(int argc, char *argv[]) {
     TestSum(&model, ntrial, r);
     printf("[%d] !!!TestSum pass, iter=%d\n", rank, r);
     rabit::LazyCheckPoint(&model);
-    printf("[%d] !!!CheckPont pass, iter=%d\n", rank, r);
+    printf("[%d] !!!CheckPoint pass, iter=%d\n", rank, r);
   }
   rabit::Finalize();
   return 0;
diff --git a/test/local_recover.cc b/test/local_recover.cc
index a63bd2f8..1f0b28b3 100644
--- a/test/local_recover.cc
+++ b/test/local_recover.cc
@@ -130,7 +130,7 @@ int main(int argc, char *argv[]) {
     TestSum(&model, &local, ntrial, r);
     printf("[%d] !!!TestSum pass, iter=%d\n", rank, r);
     rabit::CheckPoint(&model, &local);
-    printf("[%d] !!!CheckPont pass, iter=%d\n", rank, r);
+    printf("[%d] !!!CheckPoint pass, iter=%d\n", rank, r);
   }
   rabit::Finalize();
   return 0;
diff --git a/test/local_recover.py b/test/local_recover.py
index 315acbf0..6f7fae84 100755
--- a/test/local_recover.py
+++ b/test/local_recover.py
@@ -1,6 +1,11 @@
-#!/usr/bin/python
+#!/usr/bin/env python3
+
 from __future__ import print_function
 from builtins import range
+
+import sys
+sys.path.append('../python')
+
 import rabit
 import numpy as np
 
diff --git a/test/test.mk b/test/test.mk
index 7b999507..b4b9afc4 100644
--- a/test/test.mk
+++ b/test/test.mk
@@ -1,29 +1,29 @@
 # this is a makefile used to show testcases of rabit
 .PHONY: all
 
-all: model_recover_10_10k  model_recover_10_10k_die_same model_recover_10_10k_die_hard local_recover_10_10k
+all: model_recover_10_10k  model_recover_10_10k_die_same model_recover_10_10k_die_hard local_recover_10_10k lazy_recover_10_10k_die_hard lazy_recover_10_10k_die_same ringallreduce_10_10k pylocal_recover_10_10k
 
 # this experiment test recovery with actually process exit, use keepalive to keep program alive
 model_recover_10_10k:
-	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=10 model_recover 10000 mock=0,0,1,0 mock=1,1,1,0
+	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=20 model_recover 10000 mock=0,0,1,0 mock=1,1,1,0
 
 model_recover_10_10k_die_same:
-	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=10 model_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0
+	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=20 model_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0
 
 model_recover_10_10k_die_hard:
-	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=10 model_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=1,1,1,1 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0 mock=8,1,2,0 mock=4,1,3,0
+	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=20 model_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=1,1,1,1 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0 mock=8,1,2,0 mock=4,1,3,0
 
 local_recover_10_10k:
-	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=10 local_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0 mock=1,1,1,1
+	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=20 local_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0 mock=1,1,1,1
 
 pylocal_recover_10_10k:
-	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 local_recover.py 10000 mock=0,0,1,0 mock=1,1,1,0 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0 mock=1,1,1,1
+	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=20 local_recover.py 10000 mock=0,0,1,0 mock=1,1,1,0 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0 mock=1,1,1,1
 
 lazy_recover_10_10k_die_hard:
-	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=10 lazy_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=1,1,1,1 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0 mock=8,1,2,0 mock=4,1,3,0
+	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=20 lazy_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=1,1,1,1 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0 mock=8,1,2,0 mock=4,1,3,0
 
 lazy_recover_10_10k_die_same:
-	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=10 lazy_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0
+	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 --local-num-attempt=20 lazy_recover 10000 mock=0,0,1,0 mock=1,1,1,0 mock=0,1,1,0 mock=4,1,1,0 mock=9,1,1,0
 
 ringallreduce_10_10k:
-	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 model_recover 100 rabit_reduce_ring_mincount=10
+	../dmlc-core/tracker/dmlc-submit --cluster local --num-workers=10 model_recover 10000 rabit_reduce_ring_mincount=10