OS:Red Hat Enterprise Linux Server release 6.4 (Santiago) 
GP:greenplum-db-4.3.6.2-build-1-RHEL5-x86_64.zip
JDK:1.7+

192.168.1.100　　bj-gp-node1(segment master)
192.168.1.101　　bj-gp-node2(segment standby)
192.168.1.102　　bj-gp-node3(segment)
192.168.1.103　　bj-gp-node4(segment)

[root@bj-gp-node1 ~]# vi /etc/sysctl.conf
# Kernel sysctl configuration file for Red Hat Linux
#
# For binary values, 0 is disabled, 1 is enabled.  See sysctl(8) and
# sysctl.conf(5) for more details.
#
# Use '/sbin/sysctl -a' to list all possible parameters.

# Controls IP packet forwarding
net.ipv4.ip_forward = 0

# Controls source route verification
net.ipv4.conf.default.rp_filter = 1

# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0

# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 1

# Controls whether core dumps will append the PID to the core filename.
# Useful for debugging multi-threaded applications.
kernel.core_uses_pid = 1

# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1

# Disable netfilter on bridges
#net.bridge.bridge-nf-call-ip6tables = 0
#net.bridge.bridge-nf-call-iptables = 0
#net.bridge.bridge-nf-call-arptables = 0

# Controls the default maxmimum size of a mesage queue
kernel.msgmnb = 65536

# Controls the maximum size of a message, in bytes
kernel.msgmax = 65536
kernel.msgmni = 2048

kernel.sem = 250 512000 100 2048

# Controls the maximum shared segment size, in bytes
#kernel.shmmax = 68719476736
kernel.shmmax = 500000000
kernel.shmmni = 4096

# Controls the maximum number of shared memory segments, in pages
#kernel.shmall = 4294967296
kernel.shmall = 4000000000

net.ipv4.tcp_tw_recycle=1
net.ipv4.tcp_max_syn_backlog=4096
net.ipv4.ip_local_port_range = 1025 65535
net.core.netdev_max_backlog=10000
vm.overcommit_memory=2
net.ipv4.conf.all.arp_filter = 1
net.core.rmem_max = 2097152
net.core.wmem_max = 2097152