2008年7月 Archives
tcpping是一个shell脚本，运行需要 tcptraceroute 的支持，所以真正起作用的是tcptraceroute
整体安装比较简单，具体顺序是先安装tcptraceroute，然后创建tcpping脚本。
注意： Tcptraceroute需要libcap和libnet的支持，这里暂不介绍。
假定已经编译好libcap和libnet
1.编译tcptraceroute
./configure --prefix=/usr/local/tcptraceroute --with-libpcap=/usr/local/libpcap --with-libnet=/usr/local/libnet --enable-static
安装好以后把tcptraceroute放到PATH路径，这样tcpping脚本可以找到tcptraceroute。
2.使用、语法
./tcptraceroute
tcptraceroute 1.5beta7
Copyright (c) 2001-2006 Michael C. Toren <mct@toren.net>
Updates are available from http://michael.toren.net/code/tcptraceroute/
Usage: tcptraceroute [-nNFSAE] [-i <interface>] [-f <first ttl>]
[-l <packet length>] [-q <number of queries>] [-t <tos>]
[-m <max ttl>] [-pP] <source port>] [-s <source address>]
[-w <wait time>] <host> [destination port] [packet length]
#tcptraceroute www.google.com
Selected device eth0, address 212.106.15.83, port 40479 for outgoing packets
Tracing the path to www.google.com (64.233.189.99) on TCP port 80 (http), 30 hops max
...
5 219.158.4.82 44.330 ms 44.258 ms 44.032 ms
6 219.158.3.246 54.812 ms 54.760 ms 54.739 ms
7 219.158.3.130 60.441 ms 60.436 ms 60.365 ms
8 219.158.32.230 51.775 ms 49.505 ms 49.407 ms
9 64.233.175.207 60.484 ms 60.637 ms 77.707 ms
10 66.249.94.34 49.639 ms 61.653 ms 54.145 ms
11 hk-in-f99.google.com (64.233.189.99) [open] 50.267 ms 50.059 ms 50.111 ms
和traceroute的区别
#traceroute www.google.com
traceroute: Warning: www.google.com has multiple addresses; using 64.233.189.104
traceroute to www-china.l.google.com (64.233.189.104), 30 hops max, 38 byte packets
...
5 219.158.4.38 (219.158.4.38) 42.247 ms 42.551 ms 42.519 ms
6 219.158.3.58 (219.158.3.58) 42.140 ms 42.107 ms 42.118 ms
7 219.158.3.130 (219.158.3.130) 47.976 ms 47.900 ms 48.013 ms
8 219.158.32.230 (219.158.32.230) 37.038 ms 36.947 ms 37.058 ms
9 64.233.175.207 (64.233.175.207) 48.005 ms 47.987 ms 48.022 ms
10 66.249.94.6 (66.249.94.6) 50.673 ms 66.249.94.34 (66.249.94.34) 46.763 ms 37.104 ms
11 hk-in-f104.google.com (64.233.189.104) 47.841 ms 47.878 ms 47.826 ms
tcpping的使用：
./tcpping
tcpping v1.6 Richard van den Berg <richard@vdberg.org>
Usage: tcpping [-d] [-c] [-C] [-w sec] [-q num] [-x count] ipaddress [port]
-d print timestamp before every result
-c print a columned result line
-C print in the same format as fping's -C option
-w wait time in seconds (defaults to 3)
-r repeat every n seconds (defaults to 1)
-x repeat n times (defaults to unlimited)
See also: man tcptraceroute
http://michael.toren.net/code/tcptraceroute/
使用tcpping
#tcpping -c www.google.com
0 1217065416 50.126 hk-in-f99.google.com (64.233.189.99)
1 1217065417 50.170 hk-in-f99.google.com (64.233.189.99)
2 1217065418 48.035 hk-in-f104.google.com (64.233.189.104)
3 1217065419 47.858 hk-in-f104.google.com (64.233.189.104)
4 1217065420 50.024 hk-in-f99.google.com (64.233.189.99)
5 1217065421 49.756 hk-in-f147.google.com (64.233.189.147)
6 1217065422 50.155 hk-in-f99.google.com (64.233.189.99)
7 1217065423 49.688 hk-in-f147.google.com (64.233.189.147)
可以看到google的几个不同IP。
使用ping
#ping www.google.com
PING www-china.l.google.com (64.233.189.147) 56(84) bytes of data.
64 bytes from hk-in-f147.google.com (64.233.189.147): icmp_seq=0 ttl=244 time=49.5 ms
64 bytes from hk-in-f147.google.com (64.233.189.147): icmp_seq=1 ttl=244 time=49.5 ms
64 bytes from hk-in-f147.google.com (64.233.189.147): icmp_seq=2 ttl=244 time=49.5 ms
64 bytes from hk-in-f147.google.com (64.233.189.147): icmp_seq=3 ttl=244 time=49.4 ms
64 bytes from hk-in-f147.google.com (64.233.189.147): icmp_seq=4 ttl=244 time=49.5 ms
其他具体的使用方法可以查看脚本的参数
# tcptraceroute --help
tcptraceroute 1.5beta7
Copyright (c) 2001-2006 Michael C. Toren <mct@toren.net>
Updates are available from http://michael.toren.net/code/tcptraceroute/
Usage: tcptraceroute [-nNFSAE] [-i <interface>] [-f <first ttl>]
[-l <packet length>] [-q <number of queries>] [-t <tos>]
[-m <max ttl>] [-pP] <source port>] [-s <source address>]
[-w <wait time>] <host> [destination port] [packet length]
-n
Display numeric output, rather than doing a reverse DNS lookup for each hop. By default, reverse lookups are never attempted on RFC1918
address space, regardless of the -n flag.
-N
Perform a reverse DNS lookup for each hop, including RFC1918 addresses.
-f
Set the initial TTL used in the first outgoing packet. The default is 1.
-m
Set the maximum TTL used in outgoing packets. The default is 30.
-p
Use the specified local TCP port in outgoing packets. The default is to obtain a free port from the kernel using bind(2). Unlike with traditional
traceroute(8), this number will not increase with each hop.
-s
Set the source address for outgoing packets. See also the -i flag.
-i
Use the specified interface for outgoing packets.
-q
Set the number of probes to be sent to each hop. The default is 3.
-w
Set the timeout, in seconds, to wait for a response for each probe. The default is 3.
-S
Set the TCP SYN flag in outgoing packets. This is the default, if neither -S or -A is specified.
-A
Set the TCP ACK flag in outgoing packets. By doing so, it is possible to trace through stateless firewalls which permit outgoing TCP connections.
-E
Send ECN SYN packets, as described in RFC2481.
-t
Set the IP TOS (type of service) to be used in outgoing packets. The default is not to set any TOS.
-F
Set the IP "don't fragment" bit in outgoing packets.
-l
Set the total packet length to be used in outgoing packets. If the length is greater than the minimum size required to assemble the necessary probe
packet headers, this value is automatically increased.
-d
Enable debugging, which may or may not be useful.
下面是tcpping的脚本：
tcpping
习惯总是使用su来切换用户，但是今天在修改了新用户的环境变量后发现su 和su - 还存在些许区别。
su newuser保留原来用户(olduser)的环境变量，新用户下的环境bash设置无效。
而 su - newuser 则使用newuser的环境变量，新用户的~/.bash_profile生效。
使用Volano对jvm性能测试
网络测试报告：
http://www.volano.com/report/index.html
一、以下是2hei的测试情况：
原理：
启动volano server 会根据jdk的版本来设定默认的jvm值，然后启动简化版的Tomcat，并部署VolanoChat聊天系统；
启动客户端对VolanoChat进行连接，客户端模拟聊天者并发发送大量的消息，来测试jvm的性能。
使用JDK1.6
设定1.6的环境变量
export JAVA_HOME=/home/jdk1.6.0_06
export PATH=$JAVA_HOME/bin:$PATH
启动server：
./loopserver.sh sun16
java version "1.6.0_06"
Java(TM) SE Runtime Environment (build 1.6.0_06-b02)
Java HotSpot(TM) Server VM (build 10.0-b22, mixed mode)
/home/jdk1.6.0_06/bin/java -server -Xmx64m -Dinstall.root=. -Dcatalina.home=. -cp .:lib/bootstrap.jar:lib/catalina.jar:lib/naming-common.jar:lib/naming-resources.jar:lib/servlet.jar:lib/servlets-common.jar:lib/servlets-default.jar:lib/volanochat-server.jar:lib/xerces.jar COM.volano.Main
VolanoChat(TM) Server Version 2.5.0.9
Copyright (C) 1996-2002 Volano LLC. All rights reserved.
Loading server properties from "/home/www.2hei.net/soft/voooo/conf/properties.txt".
www.2hei.net:8000 VolanoChatPro - unlimited connections.
Apache Tomcat/4.0.3
启动client，对server进行压力测试
./loopclient.sh sun16
ulimit -Sn = 1024
java version "1.6.0_06"
Java(TM) SE Runtime Environment (build 1.6.0_06-b02)
Java HotSpot(TM) Server VM (build 10.0-b22, mixed mode)
/home/jdk1.6.0_06/bin/java -server -Xmx64m -Dinstall.root=. -Dcatalina.home=. -cp .:lib/bootstrap.jar:lib/catalina.jar:lib/naming-common.jar:lib/naming-resources.jar:lib/servlet.jar:lib/servlets-common.jar:lib/servlets-default.jar:lib/volanochat-server.jar:lib/xerces.jar COM.volano.Mark -run
执行结果：
java.vendor = Sun Microsystems Inc.
java.vendor.url = http://java.sun.com/
java.version = 1.6.0_06
java.class.version = 50.0
java.compiler = null
os.name = Linux
os.version = 2.6.9-67.0.15.ELsmp
os.arch = i386
VolanoMark version = 2.5.0.9
Messages sent = 20000
Messages received = 380000
Total messages = 400000
Elapsed time = 12.862 seconds
Average throughput = 31099 messages per second
使用JDK1.4：
设定1.4的环境变量
export JAVA_HOME=/home/j2sdk1.4.2_17
export PATH=$JAVA_HOME/bin:$PATH
./loopserver.sh sun14
ulimit -Sn = 1024
java version "1.4.2_17"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_17-b06)
Java HotSpot(TM) Server VM (build 1.4.2_17-b06, mixed mode)
/home/j2sdk1.4.2_17/bin/java -server -Xmx64m -Dinstall.root=. -Dcatalina.home=. -cp .:lib/bootstrap.jar:lib/catalina.jar:lib/naming-common.jar:lib/naming-resources.jar:lib/servlet.jar:lib/servlets-common.jar:lib/servlets-default.jar:lib/volanochat-server.jar:lib/xerces.jar COM.volano.Main
VolanoChat(TM) Server Version 2.5.0.9
Copyright (C) 1996-2002 Volano LLC. All rights reserved.
Loading server properties from "/home/www.2hei.net/soft/voooo/conf/properties.txt".
www.2hei.net:8000 VolanoChatPro - unlimited connections.
Apache Tomcat/4.0.3
./loopclient.sh sun14
ulimit -Sn = 1024
java version "1.4.2_17"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_17-b06)
Java HotSpot(TM) Server VM (build 1.4.2_17-b06, mixed mode)
/home/j2sdk1.4.2_17/bin/java -server -Xmx64m -Dinstall.root=. -Dcatalina.home=. -cp .:lib/bootstrap.jar:lib/catalina.jar:lib/naming-common.jar:lib/naming-resources.jar:lib/servlet.jar:lib/servlets-common.jar:lib/servlets-default.jar:lib/volanochat-server.jar:lib/xerces.jar COM.volano.Mark -run
执行结果：
java.vendor = Sun Microsystems Inc.
java.vendor.url = http://java.sun.com/
java.version = 1.4.2_17
java.class.version = 48.0
java.compiler = null
os.name = Linux
os.version = 2.6.9-67.0.15.ELsmp
os.arch = i386
VolanoMark version = 2.5.0.9
Messages sent = 20000
Messages received = 380000
Total messages = 400000
Elapsed time = 15.739 seconds
Average throughput = 25415 messages per second
二、测试结论：
在同等的硬件配置及操作系统下，测试每次都发送400000条数据，从执行时间和吞吐量上看jdk1.6的性能要比jdk1.4的高一些，
如吞吐量分别是每秒31099，25415。
网上其他的关于jdk性能的比较
下面是sun对与J2SE 1.4.2 和J2SE 5.0的性能比较
http://java.sun.com/performance/reference/whitepapers/5.0_performance.html
sun五个升级到jdk1.5的原因。 比如性能优化，稳定性优化，还有64位的支持等等
http://java.sun.com/developer/technicalArticles/J2SE/5reasons.html
siege是一个开源的压力测试用具，有点类似apache的ab
http://www.joedog.org/Siege/Manual
download from ftp://ftp.joedog.org/pub/siege
./configure --prefix=/home/siege && make && make install
[root@ bin]# ./siege
SIEGE 2.67
Usage: siege [options]
siege [options] URL
siege -g URL
Options:
-V, --version VERSION, prints version number to screen.
-h, --help HELP, prints this section.
-C, --config CONFIGURATION, show the current configuration.
-v, --verbose VERBOSE, prints notification to screen.
-g, --get GET, pull down headers from the server and display HTTP
transaction. Great for web application debugging.
-c, --concurrent=NUM CONCURRENT users, default is 10
-u, --url="URL" Deprecated. Set URL as the last argument.
-i, --internet INTERNET user simulation, hits the URLs randomly.
-b, --benchmark BENCHMARK, signifies no delay for time testing.
-t, --time=NUMm TIME based testing where "m" is the modifier S, M, or H
no space between NUM and "m", ex: --time=1H, one hour test.
-r, --reps=NUM REPS, number of times to run the test, default is 25
-f, --file=FILE FILE, change the configuration file to file.
-R, --rc=FILE RC, change the siegerc file to file. Overrides
the SIEGERC environmental variable.
-l, --log LOG, logs the transaction to PREFIX/var/siege.log
-m, --mark="text" MARK, mark the log file with a string separator.
-d, --delay=NUM Time DELAY, random delay between 1 and num designed
to simulate human activity. Default value is 3
-H, --header="text" Add a header to request (can be many)
-A, --user-agent="text" Sets User-Agent in request
siege 的使用方法
$ ./siege -u www.google.com -d1 -r10 -c25
-u has been deprecated.
提示-u参数已经不推荐了
也可以使用url列表的方式：
./siege -c 20 -r 30 -f url.txt
vi url.txt
http://www.google.com
运行的结果如下：
** SIEGE 2.67
** Preparing 20 concurrent users for battle.
The server is now under siege...
HTTP/1.1 200 0.17 secs: 6385 bytes ==> /
HTTP/1.1 200 0.17 secs: 6385 bytes ==> /
HTTP/1.1 200 0.17 secs: 6385 bytes ==> /
HTTP/1.1 200 0.17 secs: 6385 bytes ==> /
HTTP/1.1 200 0.17 secs: 6375 bytes ==> /
HTTP/1.1 200 0.17 secs: 6375 bytes ==> /
HTTP/1.1 200 0.18 secs: 6385 bytes ==> /
HTTP/1.1 200 0.18 secs: 6375 bytes ==> /
HTTP/1.1 200 0.33 secs: 6385 bytes ==> /
done.
Transactions: 600 hits
Availability: 100.00 %
Elapsed time: 24.53 secs
Data transferred: 3.66 MB
Response time: 0.18 secs
Transaction rate: 24.46 trans/sec
Throughput: 0.15 MB/sec
Concurrency: 4.46
Successful transactions: 600
Failed transactions: 0
Longest transaction: 3.40
Shortest transaction: 0.17
FILE: /home/siege/var/siege.log
You can disable this annoying message by editing
the .siegerc file in your home directory; change
the directive 'show-logfile' to false.
JDK1.5提供JMX remote的管理工具Jconsole，可以监控Java运行程序的内存使用情况、活动线程数量、类装载的数量、MBeans的状态、虚拟机的各种信息等，还可以执行MBean公开的方法或强制进行垃圾回收。因为Apusic应用服务器实现标准的JMX接口，因此也可以使用Jconsole进行监控。
下面是在windows端对Linux的java应用（Resin）的JVM进行监控。
windows： 安装 jdk1.6.0_06 http://java.sun.com/javase/downloads/index.jsp
Linux：Resin2.1.x + jdk1.6
启动resin ，增加jvm监控的指令：
可以在java启动参数添加，
如： httpd.sh 或者 wrapper.pl 里面
vi http.sh
args="***" 把 需要启动jvm选项加入。
#指定远程服务器的端口
-Dcom.sun.management.jmxremote.port=12345
#指定远程服务器的用户认证
-Dcom.sun.management.jmxremote.password.file=$JRE_HOME/lib/management/password.properties
-Dcom.sun.management.jmxremote.access.file=$JRE_HOME/lib/management/access.properties
使用密码：
#JRE_HOME/lib/management/jmxremote.password.template
cp jmxremote.password.template password.properties
chmod 600 password.properties
#默认用户名 密码为：
monitorRole QED
controlRole R&D
#默认权限
#cp jmxremote.access access.properties
#设置权限
monitorRole readonly
controlRole readwrite
#也可以使用禁止用户认证
com.sun.management.jmxremote.authenticate=false
也可以使用ssl连接
这里先不用
com.sun.management.jmxremote.ssl=false
说明： 如果没有启动com.sun.management.jmxremote 的配置 ， 远程连接会提示：
error during jrmp connection establishment ; nested exception is
如果无法连接有可能是linux服务器的hostname存在问题
#修改hostname
/etc/hosts 把127.0.0.1修改为外网卡IP，如192.168.1.100
还有
/etc/sysconfig/network
#启动resin
$RESIN_HOME/bin/http.sh start
#查看是否已经启动
#ps -x
8681 pts/0 S 0:00 perl bin/wrapper.pl -chdir -name httpd -class com.caucho.server.http.HttpServer -J-server -verbose -Dcom.
8683 pts/0 Sl 0:04 /home/2hei.net/jdk1.6.0_06/bin/java -server -Dcom.sun.management.jmxremote.port=12345 -Dcom.sun.management.jmxremo
#查看端口
#netstat -an
tcp 0 0 127.0.0.1:35844 127.0.0.1:35848 ESTABLISHED
tcp 0 0 :::8080 :::* LISTEN
tcp 0 0 :::12345 :::* LISTEN
-Dcom.sun.management.jmxremote.authenticate=false
#是否使用ssl
-Dcom.sun.management.jmxremote.ssl=false"
windows下
jconsole命令在 $JAVA_HOME/bin 下
cmd:\>jconsole
#启动
连接远程
192.168.1.100:12345
controlRole R&D
参考：
http://java.sun.com/javase/6/docs/technotes/guides/management/jconsole.html
http://java.sun.com/javase/6/docs/technotes/tools/solaris/keytool.html
shell变量的作用域
while read line
do
str[$i]=$line1
echo $i
echo ${str[i]}
let i=i+1
done < data
len=${#str[@]}
echo $len
$len长度为实际data文件的行数
str[]变量的作用域一直有效
===================
cat data|while read line
do
str[$i]=$line1
echo $i
echo ${str[i]}
let i=i+1
done
len=${#str[@]}
echo $len
$len长度为0
说明str[]变量的作用域到done结束即失效。
原因是局部变量是普通的变量，仅在创建它的Shell中有效。
cat data|while read line 使用了管道符 "|"
表明父shell中的局部变量不会传递到子shell中
kernel panic 主要有以下几个出错提示：
kernel panic - not syncing: Attempted to kill the idle task!
kernel panic - not syncing: killing interrupt handler!
Kernel Panic - not syncing：Attempted to kill init !
查看了一下 linux的源码文件，找到相关位置
kernel/panic.c
NORET_TYPE void panic(const char * fmt, ...)
{
static char buf[1024];
va_list args;
bust_spinlocks(1);
va_start(args, fmt);
vsnprintf(buf, sizeof(buf), fmt, args);
va_end(args);
printk(KERN_EMERG "Kernel panic - not syncing: %s\n",buf);
bust_spinlocks(0);
kernel/exit.c
if (unlikely(in_interrupt()))
panic("Aiee, killing interrupt handler!"); #中断处理
if (unlikely(!tsk->pid))
panic("Attempted to kill the idle task!"); #空任务
if (unlikely(tsk->pid == 1))
panic("Attempted to kill init!"); #初始化
从其他源文件和相关文档看到应该有几种原因：
1、硬件问题
使用了 SCSI-device 并且使用了未知命令
#WDIOS_TEMPPANIC Kernel panic on temperature trip
#
# The SETOPTIONS call can be used to enable and disable the card
# and to ask the driver to call panic if the system overheats.
#
# If one uses a SCSI-device of unsupported type/commands, one
# immediately runs into a kernel-panic caused by Command Error. To better
# understand which SCSI-command caused the problem, I extended this
# specific panic-message slightly.
#
#read/write causes a command error from
# the subsystem and this causes kernel-panic
2、系统过热
如果系统过热会调用panci，系统挂起
#WDIOS_TEMPPANIC Kernel panic on temperature trip
#
# The SETOPTIONS call can be used to enable and disable the card
# and to ask the driver to call panic if the system overheats.
3、文件系统引起
#A variety of panics and hangs with /tmp on a reiserfs filesystem
#Any other panic, hang, or strange behavior
#
# It turns out that there's a limit of six environment variables on the
# kernel command line. When that limit is reached or exceeded, argument
# processing stops, which means that the 'root=' argument that UML
# usually adds is not seen. So, the filesystem has no idea what the
# root device is, so it panics.
# The fix is to put less stuff on the command line. Glomming all your
# setup variables into one is probably the best way to go.
Linux内核命令行有6个环境变量。如果即将达到或者已经超过了的话 root= 参数会没有传进去
启动时会引发panics错误。
vi grub.conf
#####################
title Red Hat Enterprise Linux AS (2.6.9-67.0.15.ELsmp)
root (hd0,0)
kernel /boot/vmlinuz-2.6.9-67.0.15.ELsmp ro root=LABEL=/
initrd /boot/initrd-2.6.9-67.0.15.ELsmp.img
title Red Hat Enterprise Linux AS-up (2.6.9-67.EL)
root (hd0,0)
kernel /boot/vmlinuz-2.6.9-67.EL ro root=LABEL=/
initrd /boot/initrd-2.6.9-67.EL.img
应该是 其中的 root=LABEL=/ 没有起作用。
4、内核更新
网上相关文档多半是因为升级内核引起的，建议使用官方标准版、稳定版
另外还有使用磁盘的lvm 逻辑卷，添加CPU和内存。可在BIOS中禁掉声卡驱动等不必要的设备。
也有报是ext3文件系统的问题。
解决： 手工编译内核，把 ext3相关的模块都编译进去，
5、处理panic后的系统自动重启
panic.c源文件有个方法，当panic挂起后，指定超时时间，可以重新启动机器
if (panic_timeout > 0)
{
int i;
/*
* Delay timeout seconds before rebooting the machine.
* We can't use the "normal" timers since we just panicked..
*/
printk(KERN_EMERG "Rebooting in %d seconds..",panic_timeout);
for (i = 0; i < panic_timeout; i++) {
touch_nmi_watchdog();
mdelay(1000);
}
修改方法：
/etc/sysctl.conf文件中加入
kernel.panic = 30 #panic错误中自动重启，等待时间为30秒
kernel.sysrq=1 #激活Magic SysRq！ 否则，键盘鼠标没有响应
