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Oracle GlassFish Server 3.1 Performance Tuning Guide |
1. Overview of GlassFish Server Performance Tuning
3. Tuning the GlassFish Server
4. Tuning the Java Runtime System
5. Tuning the Operating System and Platform
To Determine an Optimal UDP Buffer Size
To Set the UDP Buffer Size on Linux Systems
Solaris 10 Platform-Specific Tuning Information
Sizing the Connection Hash Table
Tuning UltraSPARC CMT-Based Systems
To tune for maximum performance on Linux, you need to make adjustments to the following:
The following parameters must be added to the /etc/rc.d/rc.local file that gets executed during system startup.
<-- begin #max file count updated ~256 descriptors per 4Mb. Specify number of file descriptors based on the amount of system RAM. echo "6553" > /proc/sys/fs/file-max #inode-max 3-4 times the file-max #file not present!!!!! #echo"262144" > /proc/sys/fs/inode-max #make more local ports available echo 1024 25000 > /proc/sys/net/ipv4/ip_local_port_range #increase the memory available with socket buffers echo 2621143 > /proc/sys/net/core/rmem_max echo 262143 > /proc/sys/net/core/rmem_default #above configuration for 2.4.X kernels echo 4096 131072 262143 > /proc/sys/net/ipv4/tcp_rmem echo 4096 13107262143 > /proc/sys/net/ipv4/tcp_wmem #disable "RFC2018 TCP Selective Acknowledgements," and "RFC1323 TCP timestamps" echo 0 > /proc/sys/net/ipv4/tcp_sack echo 0 > /proc/sys/net/ipv4/tcp_timestamps #double maximum amount of memory allocated to shm at runtime echo "67108864" > /proc/sys/kernel/shmmax #improve virtual memory VM subsystem of the Linux echo "100 1200 128 512 15 5000 500 1884 2" > /proc/sys/vm/bdflush #we also do a sysctl sysctl -p /etc/sysctl.conf -- end -->
Additionally, create an /etc/sysctl.conf file and append it with the following values:
<-- begin #Disables packet forwarding net.ipv4.ip_forward = 0 #Enables source route verification net.ipv4.conf.default.rp_filter = 1 #Disables the magic-sysrq key kernel.sysrq = 0 fs.file-max=65536 vm.bdflush = 100 1200 128 512 15 5000 500 1884 2 net.ipv4.ip_local_port_range = 1024 65000 net.core.rmem_max= 262143 net.core.rmem_default = 262143 net.ipv4.tcp_rmem = 4096 131072 262143 net.ipv4.tcp_wmem = 4096 131072 262143 net.ipv4.tcp_sack = 0 net.ipv4.tcp_timestamps = 0 kernel.shmmax = 67108864
You may need to increase the number of file descriptors from the default. Having a higher number of file descriptors ensures that the server can open sockets under high load and not abort requests coming in from clients.
Start by checking system limits for file descriptors with this command:
cat /proc/sys/fs/file-max 8192
The current limit shown is 8192. To increase it to 65535, use the following command (as root):
echo "65535" > /proc/sys/fs/file-max
To make this value to survive a system reboot, add it to /etc/sysctl.conf and specify the maximum number of open files permitted:
fs.file-max = 65535
Note that the parameter is not proc.sys.fs.file-max, as one might expect.
To list the available parameters that can be modified using sysctl:
sysctl -a
To load new values from the sysctl.conf file:
sysctl -p /etc/sysctl.conf
To check and modify limits per shell, use the following command:
limit
The output will look something like this:
cputime unlimited filesize unlimited datasize unlimited stacksize 8192 kbytes coredumpsize 0 kbytes memoryuse unlimited descriptors 1024 memorylocked unlimited maxproc 8146 openfiles 1024
The openfiles and descriptors show a limit of 1024. To increase the limit to 65535 for all users, edit /etc/security/limits.conf as root, and modify or add the nofile setting (number of file) entries:
* soft nofile 65535 * hard nofile 65535
The character “*” is a wildcard that identifies all users. You could also specify a user ID instead.
Then edit /etc/pam.d/login and add the line:
session required /lib/security/pam_limits.so
On Red Hat, you also need to edit /etc/pam.d/sshd and add the following line:
session required /lib/security/pam_limits.so
On many systems, this procedure will be sufficient. Log in as a regular user and try it before doing the remaining steps. The remaining steps might not be required, depending on how pluggable authentication modules (PAM) and secure shell (SSH) are configured.
To change virtual memory settings, add the following to /etc/rc.local:
echo 100 1200 128 512 15 5000 500 1884 2 > /proc/sys/vm/bdflush
For more information, view the man pages for bdflush.
To ensure that the network interface is operating in full duplex mode, add the following entry into /etc/rc.local:
mii-tool -F 100baseTx-FD eth0
where eth0 is the name of the network interface card (NIC).
Use this command:
/sbin/hdparm -t /dev/hdX
Use this command:
/sbin/hdparm -d1 /dev/hdX
Given that DMA is not enabled by default, the transfer rate might have improved considerably. In order to do this at every reboot, add the /sbin/hdparm -d1 /dev/hdX line to /etc/conf.d/local.start, /etc/init.d/rc.local, or whatever the startup script is called.
For information on SCSI disks, see: System Tuning for Linux Servers — SCSI.
echo 30 > /proc/sys/net/ipv4/tcp_fin_timeout echo 60000 > /proc/sys/net/ipv4/tcp_keepalive_time echo 15000 > /proc/sys/net/ipv4/tcp_keepalive_intvl echo 0 > /proc/sys/net/ipv4/tcp_window_scaling
# Disables packet forwarding net.ipv4.ip_forward = 0 # Enables source route verification net.ipv4.conf.default.rp_filter = 1 # Disables the magic-sysrq key kernel.sysrq = 0 net.ipv4.ip_local_port_range = 1204 65000 net.core.rmem_max = 262140 net.core.rmem_default = 262140 net.ipv4.tcp_rmem = 4096 131072 262140 net.ipv4.tcp_wmem = 4096 131072 262140 net.ipv4.tcp_sack = 0 net.ipv4.tcp_timestamps = 0 net.ipv4.tcp_window_scaling = 0 net.ipv4.tcp_keepalive_time = 60000 net.ipv4.tcp_keepalive_intvl = 15000 net.ipv4.tcp_fin_timeout = 30
sysctl -p /etc/sysctl.conf
tcp_recv_hiwat ndd /dev/tcp 8129 32768
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