clear sendmail mail queue

rm -f /var/spool/mqueue/*

php memcache

1. install memcached

wget http://dag.wieers.com/rpm/packages/rpmforge-release/rpmforge-release-0.3.6-1.el5.rf.x86_64.rpm
rpm --install rpmforge-release-0.3.6-1.el5.rf.x86_64.rpm

Or
http://dag.wieers.com/rpm/packages/rpmforge-release/rpmforge-release-0.3.6-1.el5.rf.i386.rpm
rpm --install rpmforge-release-0.3.6-1.el5.rf.i386.rpm

yum install --enablerepo=rpmforge memcached

2. download memcache.php
wget http://livebookmark.net/memcachephp/memcachephp.zip

3. start memcache

service memcached restart
/usr/local/bin/memcached -d -u root -m 512






Reference:
http://www.howtoforge.com/php_memcache_centos5.0
http://www.nioxiao.com/php-memcached
http://www.ibm.com/developerworks/cn/opensource/os-php-fastapps3/index.html

smtp receive mail error

ERROR:
(reason: 553 5.3.5 system config error)
config error: mail loops back to me (MX problem?)
554 5.3.5 Local configuration error
Diagnostic-Code: SMTP; 553 5.3.5 system config error

SOLUTION:
If it is Sendmail that you're using, then you should be able to just edit the /etc/mail/local-host-names file and add your domain names that the MTA should recognize as being its self.

REFERENCE:
http://www.webdeveloper.com/forum/showthread.php?t=173882
open webmail

check network listen and connect

netstat -anp

config smtp server using sendmail

service saslauthd restart
service sendmail restart

PHPMailer
http://sourceforge.net/projects/phpmailer/files/

redhat下的sendmail+smtp 的配置
http://www.myfaq.com.cn/2005September/2005-09-13/198608.html

用Sendmail配置你的第一台e-mail服务器
http://www.5dmail.net/html/2004-10-26/20041026133839.htm

Configuring Linux Mail Servers
http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch21_:_Configuring_Linux_Mail_Servers

setup Chinese Font in Nokia E75

1. get a cer file and "DOSPY SignTool v2.2.9.0627.exe" from http://cer.dospy.com/
2. get FontRouter.LT.for.v9.Build20071109.unsigned.sis
3. use the cer file sign FontRouter get Administrator_Signed_FontRouter.LT.for.v9.Build20071109.sisx
4. setup FontRouter on E75
5. copy Simsun Nina ZL by Loname.ttf to E:/data/fonts
6. restart E75

http://www.mitbbs.com/clubarticle/smartphone/30994727_0.html
http://www.dospy.com/bbs/thread-4550277-1-1.html

createElement('div').innerHTML

function fnGetId(){
var aa = document.getElementById('aa');
alert(aa.innerHTML);
var bb = document.createElement('div');
bb.innerHTML = '

bb

';
aa.insertBefore(bb, aa.firstChild);
alert(aa.innerHTML);
}

to easy use element.innerHTML, you should document.createElement('div'), but not document.createElement('p');

license server of simics

export LM_LICENSE_FILE=/opt/virtutech/simics-3.0.31/licenses/simics.lic
lmgrd &

gcc keep library path information in binary

-Wl,-rpath -Wl,/op/gcc-4.2.2/lib

coustom sql query on propel

$dbMap = Propel::getDatabaseMap();
$con = Propel::getConnection();
$sql = 'xxx sql query...';
$stmt = $con->prepareStatement($sql);
$rs = $stmt->executeQuery(ResultSet::FETCHMODE_NUM);
return XXXPeer::populateObjects($rs);

get google search result

http://code.google.com/intl/zh-CN/apis/ajaxsearch/documentation/

$url = "http://ajax.googleapis.com/ajax/services/search/web?v=1.0&q=Paris%20Hilton";

// sendRequest
// note how referer is set manually
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_REFERER, "http://www.mysite.com/index.html");
$body = curl_exec($ch);
curl_close($ch);

// now, process the JSON string
$json = json_decode($body);
// now have some fun with the results...

sort links on wordpress

wp_list_bookmarks($args = '') {
$defaults = array(
'orderby' => 'rating'


Change the orderby parameter in function wp_list_bookmarks.

set time and date in Linux

date --set="2 OCT 2006 18:00:00"

bind & named DNS service

http://zh.linuxvirtualserver.org/node/695
http://hi.baidu.com/it0820/blog/item/d37cb7021b7e677f3812bb8e.html
http://blog.csdn.net/orapeasant/archive/2007/09/26/1801395.aspx

SimFlex changing for Sparc+Linux

/opt/virtutech/flexus-3.0.0/components/DecoupledFeeder/SimicsTracer.cpp
line 389
//DBG_Assert(false);

/opt/virtutech/flexus-3.0.0/core/simics/mai_api.hpp
line 386
//DBG_Assert(false);

/opt/virtutech/flexus-3.0.0/core/simics/sparcmmu.cpp
line 1297
FM_COPY_LIST_FROM_SIMICS


/opt/virtutech/flexus-3.0.0/components/uArch/CoreModel/cycle.cpp
line 1321
//DBG_Assert( getTL() + 1 < 5, ( << theName << " Trap when TL == 5. Processor enters RED_state. Unsupported." ) );

host ip file

Windows 95/98/Me c:\windows\hosts

Windows NT/2000/XP Pro c:\winnt\system32\drivers\etc\hosts

Windows XP Home c:\windows\system32\drivers\etc\hosts

Linux (/etc/hosts)

create multiple IP for one net card

ifconfig eth0:0 xx.xx.xx.xx netmask xx.xx.xx.xx

Reference:
http://publish.it168.com/2005/0925/20050925041401.shtml

create a scsi disk on Simics

1. create a image file
craff --decompress -o mydisk.img mydisk.craff

2. edit machine config file

$scsi_disk2 = (create-std-scsi-disk scsi_id = 2 size = $disk_size)

$scsi_bus.connect $scsi_disk2

@image2 = sim.objects[simenv.scsi_disk2].object_list['sd_image']
@image2.files = [["/mnt/sdb1/simics_image/mydisk.img", simenv.disk_perm, 0, simenv.disk_size]]

4. create partition on new disk
fdisk /dev/sdb

5. format new disk
mkfs.ext3 /dev/sdb1

5. mount new disk
mount /dev/sdb1 /mnt/sdb1

simics profiling cache miss

./simics -stall targets/sunfire/walnut-common.simics

list-components
list-modules
list-objects

cache_cpu0.add-profiler type = data-read-miss-per-instruction
cache_cpu0.add-profiler type = data-write-miss-per-instruction

c 10000000
r

cache_cpu0.statistics
cache_cpu0_prof_data_read_miss_per_instruction.address-profile-data



http://youngdean.spaces.live.com/blog/cns!C9DCEEC5C7C0B32F!619.entry
http://youngdean.spaces.live.com/blog/cns!C9DCEEC5C7C0B32F!640.entry
http://youngdean.spaces.live.com/blog/cns!C9DCEEC5C7C0B32F!641.entry

submit and update sitemap.xml to Google

http://www.google.com/support/webmasters/bin/answer.py?answer=34609

To resubmit your Sitemap using an HTTP request:

1. Issue your request to the following URL:

   www.google.com/webmasters/tools/ping?sitemap=sitemap_url

   For example, if your Sitemap is located at http://www.example.com/sitemap.gz, your URL will become:

   www.google.com/webmasters/tools/ping?sitemap=http://www.example.com/sitemap.gz

2. URL encode everything after the /ping?sitemap=:

   www.google.com/webmasters/tools/ping?sitemap=http%3A%2F%2Fwww.yoursite.com%2Fsitemap.gz

3. Issue the HTTP request using wget, curl, or another mechanism of your choosing.

complie tpcw java using gij

javac -classpath /root/setup/apache-tomcat-5.5.27/common/lib/servlet-api.jar:/root/setup/tpc-w/src/servlets/ *.java

gij connect mysql using jdbc

please using mysql-connector-java-3.0.17-ga-bin.jar
mysql jdbc driver version 3.1, 5.0, 5.1 all not available.

java -cp .:/root/setup/mysql-connector-java-3.0.17-ga/mysql-connector-java-3.0.17-ga-bin.jar TPCW_Populate


mysql -V
mysql Ver 14.7 Distrib 4.1.12, for unknown-linux-gnu (sparc) using readline 4.3


gij --version
java version "1.4.2"
gij (GNU libgcj) version 4.1.2

Copyright (C) 2006 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

setup tomcat under sparc linux

1. install gcc, g++, gcj, gij 4.1.2
../gcc-4.1.2/configure --prefix=/opt/gcc-4.1.2 --program-suffix=4.1.2 --host=sparc-redhat-linux --build=sparc-redhat-linux --target=sparc-redhat-linux

2. install java compat

3. export JAVA_HOME=/usr/lib/jvm/java-1.4.2-gcj-1.4.2.0

4. download apache-tomcat-5.5.27.tar.gz and apache-tomcat-5.5.27-compat.tar.gz

5. vi bin/setclasspath.sh
_RUNJAVA='/opt/gcc-4.1.2/bin/gij4.1.2'

6. ./startup.sh

rss feed xml parser

http://rssphp.net/
http://www.phpclasses.org/browse/package/3724.html

URL redirect 301 by .htaccess file

RewriteEngine On

RewriteCond %{HTTP_HOST} ^francetop.net [NC]
RewriteRule ^(.*)$ http://www.francetop.net/$1 [L,R=301]



Reference
http://www.webweaver.nu/html-tips/web-redirection.shtml

mysql slow queries log

1. config start slow query log
vi my.cnf

[mysqld]
set-variable=long_query_time=1
log-slow-queries=/home/www/log/mysql-log-slow-queries.log

2. restart mysql server

3. setup mysqlsla
yum install perl-DBI perl-DBD-MySQL perl-DBD-Pg
wget http://hackmysql.com/scripts/mysqlsla

4. using mysqlsla parse mysql slow query log

./mysqlsla-2.03/bin/mysqlsla --user xxx --password -lt slow --ex mysql-log-slow-queries.log --socke=/tmp/mysql.sock

./mysqlsla-1.8-DEBUG --user xxx --password --slow mysql-log-slow-queries.log --socke=/tmp/mysql.sock

web server performance analysis

1. check system load
w

2. check cpu utilization
ps

3. check memory usage and swap disk usage

eAccelerator log

eAccelerator will write many log on apache error_log, link this:

EACCELERATOR hit:"/usr/local/www/xxxx.php"

To avoid this,
add option 
eaccelerator.debug="0"
to your server php.ini configure.

php 301 redirect

header ('HTTP/1.1 301 Moved Permanently');
header ('Location: '.$location);

HTTP Status Code Definitions

301 Moved Permanently

http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html

tpcw

homepage
http://localhost:8080/tpcw/TPCW_home_interaction

Chinese character UTF8 encoding

http://theorem.ca/~mvcorks/cgi-bin/unicode.pl.cgi?start=4E00&end=9FFF
http://www.zhouhaihe.com/tool/UTF-8.htm
http://www.dc9.cn/post/85.html

ssh

problem:

ssh_exchange_identification: Connection closed by remote host


Check /etc/hosts.allow and /etc/hosts.deny.
/etc/init.d/sshd restart

/etc/ssh/sshd_config

simics usage

• start

./simics targets/x86-440bx/enterprise-common.simics
continue

• copy file into simics
  

mkisofs -r -o setup.iso ./setup/
new-file-cdrom setup.iso
cd0.insert setup
mkdir /mnt/cdrom
mount /dev/cdrom /mnt/cdrom

• network

connect-real-network 10.10.0.12
list-port-forwarding-setup
connect-real-network-port-in ethernet-link=link0 target-ip=10.10.0.12 target-port=8080 host-port=4880 -tcp

ifconfig eth0 10.10.0.12 netmask 255.255.255.0 broadcast 10.10.0.255

• setup new OS

./simics targets/sunfire/walnut-cd-install1.simics
new-file-cdrom install-sparc64-universal-2008.0.iso
cd0.insert install-sparc64-universal-2008
save-persistent-state install-phase1.state

./simics targets/sunfire/walnut-cd-install2.simics
load-persistent-state install-phase1.state
save-persistent-state install-phase2.state

./simics targets/sunfire/walnut-common.simics

bin/craff walnut-install.disk

send mail in linux server

• send a mail

mail -v -s "test of my mail on fr" xxx@gmail.com

• start mail service

service sendmail start

forward ssh server's graphic display to client

• on client:

vi /etc/ssh/ssh_config

ForwardX11 yes

• test

firefox -no-remote

• Reference:

http://www.ixdba.net/article/29/2026.html

website seo

http://www.seomoz.org
http://www.seomoz.org/blog/the-beginners-checklist-for-small-business-seo
http://www.seomoz.org/blog/the-beginners-checklist-for-learning-seo
http://www.seomoz.org/tools

SVN server configure

0. setup svn
mkdir svn_dir
cd svn_dir
svnadmin create xxx_dir
svn import . file:///xxx_dir/
svnserve -d -r svn_dir
svn co svn://domain/xxx_dir/


1. not allow anonymous access
vi conf/svnserve.conf
anon-access = none
auth-access = write
password-db = passwd

2. not cache password
vi ~/.subversion/config
store-passwords = no
store-auth-creds = no

Reference:
http://www.subversion.org.cn/svnbook/1.4/index.html
http://www.subversion.org.cn/?action-viewnews-itemid-1

Cron timer in Linux

timer task in Linux
http://cn.tech.yahoo.com/050531/55/26zxf.html

setup JDK JRE

http://java.sun.com/javase/6/webnotes/install/jdk/install-linux.html

get a setup file such as jdk-6u12-linux-i586.bin
run it directly

character web browser: lynx

get it from http://lynx.isc.org/current/index.html
very cool when you on a console


./configure
make
cp lynx.cfg /usr/local/etc/
cp samples/lynx.lss /usr/local/etc/
./lynx

msn protocol and bot

http://www.hypothetic.org/docs/msn/notification/authentication.php

serve gzip compressed content using apache 2

• enable mod_deflate in httpd.conf

• edit .htaccess file

AddOutputFilterByType DEFLATE text/html text/css text/plain text/xml application/x-javascript application/json
Header append Vary Accept-Encoding


• check


http://www.port80software.com/tools/compresscheck.asp


nginx

Nginx 0.7.x + PHP 5.2.8（FastCGI）搭建胜过Apache十倍的Web服务器（第4版） http://blog.s135.com/post/366/

setup Postgresql

1. download Postgresql (postgresql-8.3.7.tar.gz) from http://www.postgresql.org/download/

2. ./configure --prefix=

3. gmake

4. gmake install

5. adduser postgres

6. mkdir /data

7. chown postgres /data

8. initdb -D /data

9. export PATH=$PATH:/bin/

setup axis2

1. download axis2 from http://ws.apache.org/axis2/
2. unzip axis2-std-0.95-bin.zip
3. jar -xvf ../axis2.war
4. export AXIS2_HOME=....

Geronimo setup

1. download Geronimo (Geronimo 1.0 with Tomcat) from http://geronimo.apache.org/

2. follow the steps in Quick start

3. start the server
java -jar server.jar
then you can see Geronimo's welcome page in http://localhost:8080/

4. mkdir webapps as

5. Deploy an application
java -jar deployer.jar --user system --password manager deploy /HelloWorld.war

6. manage applications
http://localhost:8080/console
default user: system:manager

7. export GERONIMO_HOME=...

DBT4 setup

1. download DBT4 from http://osdldbt.sourceforge.net/

2. setup Germonimo 1.0

3. setup Axis2 version 0.95

4. setup Postgresql

5. vi scripts/pgsql/pgsql_profile.in

6. autoreconf --install

7. ./configure

8. vi src/Lcg64Rng/build.xml


9. cd src/Lcg64Rng/; ant

10. vi src/data/build.xml


11. cd src/data/; ant

12. vi src/app/build.xml


13. cd src/app/; ant

14. vi src/driver/build.xml

15. cd src/driver/; ant

16. ./scripts/pgsql/build_db.sh -e 1 -g

17. unzip axis2.war

18. cp geronimo-1.0/repository/activemq/jars/activemq-core-3.2.1.jar WEB-INF/lib/

19. cp dbt4-0.5/build/lib/Lcg64Rng.jar WEB-INF/lib/

20. cp postgresql-8.3-604.jdbc4.jar WEB-INF/lib/

21. cp dbt4-0.5/build/lib/Dbt4Service.aar WEB-INF/services/

22. jar cvf ~/axis2.war ./*

23. java -jar deployer.jar --user system --password manager deploy ~/axis2.war
now you can see dbt4 service from http://localhost:8080/axis2

24. vi scripts/myjava
JDBC_DRIVER=........./postgresql-8.3-604.jdbc4.jar

24. ./scripts/run_workload.sh -b 1 -d 1

mysql config

connect number

add to my.cnf mysqld part

max_connections=250
tmp_table_size=67108864
sort_buffer_size=4194288
table_cache=128


mysql
show variables; to query config data for mysql

build.xml java

mysql operation

/usr/bin/mysqladmin -u root password 'new-password'

GRANT ALL ON *.* TO 'myuser'@'somehost' IDENTIFIED BY 'mypass';

GRANT ALL PRIVILEGES ON *.* TO msentissi@"192.168.3.10" identified by
"yourpassword";

apache log

log format
http://httpd.apache.org/docs/2.2/mod/mod_log_config.html

apache code read

httpd.h
struct request_rec


mod_log_config.c

static const char *process_item(request_rec *r, request_rec *orig, log_format_item *item)

log_request_time()

web server measurment tool

webstone

linux context switch number query

sar -w 2 5

lxr

/tmp/lxr/bin/genxref /www/lxr/source/httpd-2.2.11
glimpseindex -n -o -H /www/lxr/source/httpd-2.2.11 www/lxr/source/httpd-2.2.11

website speed up

• page analysis tool
  

http://www.websiteoptimization.com/services/analyze/

• tutorial
  

http://www.sitepoint.com/article/web-site-optimization-steps/
http://developer.yahoo.com/performance/rules.html

• SEO

http://www.seomoz.org

msn messager robot

http://flumpcakes.co.uk/php/msn-messenger

http://www.findmysoft.com/scripts/msn_web_messenger_script/

http://www.phpclasses.org/browse/package/1407.html

get contact list from email account

http://drupal.org/node/297877

http://forums.pligg.com/modification-tutorials/9637-contact-import-msn-yahoo-gmail-myspace.html

http://www.e-citizen.com/contacts/libs/

http://www.dominican.eventsworldwide.net/include/contactgrabber/contacts/libs/


http://forums.devarticles.com/php-development-48/import-email-addressess-from-yahoo-gmail-hotmail-86529.html

http://www.phphulp.nl/php/print/4/1355/0/scripts/

configure culture in symfony

./apps/frontend/config/settings.yml: default_culture: fr

./apps/frontend/config/i18n.yml: default_culture: en

./apps/frontend/config/factories.yml:# default_culture: %SF_DEFAULT_CULTURE%

gmail contactor list

setup python
http://code.google.com/support/bin/answer.py?answer=75582

http://code.google.com/apis/contacts/docs/1.0/developers_guide_python.html

http://code.google.com/apis/gdata/articles/php_client_lib.html
http://code.google.com/apis/gdata/samples.html


http://code.google.com/apis/contacts/
http://code.google.com/apis/contacts/docs/2.0/developers_guide_protocol.html

cookie in symfony

http://www.symfony-project.org/cookbook/1_0/en/cookie
http://www.symfony-project.org/book/1_0/06-Inside-the-Controller-Layer
http://us2.php.net/setcookie

html table style

<style>
th{background-color:#bbbbbb;}
td{padding-left:5px;padding-top:5px;}
</style>

svn command

svn log -v
svn revert --recursive .

ssh to remote host without password

ssh-keygen -t dsa
ssh-copy-id -i ~/.ssh/id_dsa.pub user_name@remote_host_name

spin lock perfer same chip core

typedef struct{
int __triger;
volatile int spin;
volatile int flags[800];
volatile int queueLast;
volatile int owner;
volatile int count;
}my_spinlock_t;

int my_spin_init(my_spinlock_t * s, void *);

void my_spin_lock(my_spinlock_t * s);

void my_spin_unlock(my_spinlock_t * s);

void my_spin_dump(my_spinlock_t * s);


#define HAS_LOCK 0
#define MUST_WAIT 1
#define BACKOFF_BASE 100000


inline int g_atomic_int_exchange_and_add (int *atomic, int val)
{
int result;
__asm__ __volatile__ ("lock; xaddl %0,%1"
: "=r" (result), "=m" (*atomic)
: "0" (val), "m" (*atomic));
return result;
}

inline int g_atomic_int_compare_and_exchange (int *atomic, int oldval, int newval)
{
int result;

__asm__ __volatile__ ("lock; cmpxchgl %2, %1"
: "=a" (result), "=m" (*atomic)
: "r" (newval), "m" (*atomic), "0" (oldval));

return result;
}

int my_gettid()
{
int * p = (int*)pthread_self();
return p[18];
}


int my_spin_init(my_spinlock_t * s, void *p)
{
s->spin = HAS_LOCK;
return 0;
}

void my_spin_lock(my_spinlock_t * s)
{
volatile int i;
int b;
int cur_id, my_id = my_gettid();
my_id = my_id%8/2+1;

while( cur_id = g_atomic_int_compare_and_exchange(&s->spin, HAS_LOCK, my_id) ){
b = BACKOFF_BASE;
if(cur_id == my_id) b=0;
while(s->spin != HAS_LOCK)
for(i=b;i;i--);
}
}

void my_spin_unlock(my_spinlock_t * s)
{
s->spin = HAS_LOCK;
}

simple spin lock with backoff delay

typedef struct{
volatile int spin;
}my_spinlock_t;

int my_spin_init(my_spinlock_t * s, void *);

void my_spin_lock(my_spinlock_t * s);

void my_spin_unlock(my_spinlock_t * s);

void my_spin_dump(my_spinlock_t * s);

#define HAS_LOCK 0
#define MUST_WAIT 1
#define BACKOFF_BASE 100000


inline int g_atomic_int_exchange_and_add (int *atomic, int val)
{
int result;
__asm__ __volatile__ ("lock; xaddl %0,%1"
: "=r" (result), "=m" (*atomic)
: "0" (val), "m" (*atomic));
return result;
}

inline int g_atomic_int_compare_and_exchange (int *atomic, int oldval, int newval)
{
int result;

__asm__ __volatile__ ("lock; cmpxchgl %2, %1"
: "=a" (result), "=m" (*atomic)
: "r" (newval), "m" (*atomic), "0" (oldval));

return result == oldval;
}



int my_spin_init(my_spinlock_t * s, void *p)
{
s->spin = HAS_LOCK;
return 0;
}

void my_spin_lock(my_spinlock_t * s)
{
volatile int i;
while( !g_atomic_int_compare_and_exchange(&s->spin, HAS_LOCK, MUST_WAIT) ){
for(i=BACKOFF_BASE;i;i--);
}
}

void my_spin_unlock(my_spinlock_t * s)
{
s->spin = HAS_LOCK;
}

void my_spin_lock(my_spinlock_t * s)
{
volatile int i;
while( !g_atomic_int_compare_and_exchange(&s->spin, HAS_LOCK, MUST_WAIT) ){
while(s->spin == MUST_WAIT)
for(i=BACKOFF_BASE;i;i--);
}
}

simple spin lock

typedef struct{
int spin;
}my_spinlock_t;

int my_spin_init(my_spinlock_t * s, void *);

void my_spin_lock(my_spinlock_t * s);

void my_spin_unlock(my_spinlock_t * s);

void my_spin_dump(my_spinlock_t * s);

#define HAS_LOCK 0
#define MUST_WAIT 1


inline int g_atomic_int_compare_and_exchange (int *atomic, int oldval, int newval)
{
int result;

__asm__ __volatile__ ("lock; cmpxchgl %2, %1"
: "=a" (result), "=m" (*atomic)
: "r" (newval), "m" (*atomic), "0" (oldval));

return result == oldval;
}


int my_spin_init(my_spinlock_t * s, void *p)
{
s->spin = HAS_LOCK;
return 0;
}

void my_spin_lock(my_spinlock_t * s)
{
while( !g_atomic_int_compare_and_exchange(&s->spin, HAS_LOCK, MUST_WAIT) );
}

void my_spin_unlock(my_spinlock_t * s)
{
s->spin = HAS_LOCK;
}

queue-based spin lock

typedef struct{
volatile int flags[80];
volatile int queueLast;
volatile int owner;
}my_spinlock_t;

int my_spin_init(my_spinlock_t * s, void *);

void my_spin_lock(my_spinlock_t * s);

void my_spin_unlock(my_spinlock_t * s);


#define HAS_LOCK 0
#define MUST_WAIT 1


int g_atomic_int_exchange_and_add (int *atomic, int val)
{
int result;
__asm__ __volatile__ ("lock; xaddl %0,%1"
: "=r" (result), "=m" (*atomic)
: "0" (val), "m" (*atomic));
return result;
}

int my_gettid()
{
int * p = (int*)pthread_self();
return p[18];
}


int my_spin_init(my_spinlock_t * s, void *p)
{
int i;
s->flags[0] = HAS_LOCK;
for(i=1;i<8;i++)
s->flags[i*10] = MUST_WAIT;
s->queueLast = 0;
return 0;
}

void my_spin_lock(my_spinlock_t * s)
{
int myPlace, t;
volatile int * p;


myPlace = g_atomic_int_exchange_and_add(&s->queueLast, 1);
//myPlace = my_gettid();

t = myPlace % 8;

p = &s->flags[t*10];
while(*p == MUST_WAIT);
s->flags[t*10] = MUST_WAIT;
s->owner = myPlace;
}

void my_spin_unlock(my_spinlock_t * s)
{
int myPlace = s->owner;
s->flags[((myPlace+1) % 8)*10] = HAS_LOCK;
}



Reference
Thomas E. Anderson, "The Performance of Spin Lock Alternatives for Shared-Memory Multiprocessors", IEEE Transactions on Parallel and Distributed Systems, 1990

atomic operation function in C language

http://gcc.gnu.org/onlinedocs/gcc/Atomic-Builtins.html
http://library.gnome.org/devel/glib/2.16/glib-Atomic-Operations.html
http://java.sun.com/javase/6/docs/api/java/util/concurrent/atomic/AtomicReferenceFieldUpdater.html
https://stage.maemo.org/svn/maemo/projects/haf/branches/glib2.0/2.8.6-1osso5/glib/gatomic.c
http://www.sogou.com/labs/report/4-2.pdf

div's position and overlap

<div style="width: 150px; height: 100px; background-color: blue;">
blue
</div>
<div style="width: 100px; height: 150px; background-color: red;">
red
</div>

blue

red

<div style="width: 150px; height: 100px; background-color: blue;position: absolute;">
blue
</div>
<div style="width: 100px; height: 150px; background-color: red; position: relative;">
red
</div>

blue

red

<div style="width: 150px; height: 100px; background-color: blue;position: absolute;z-index:2;">
blue
</div>
<div style="width: 100px; height: 150px; background-color: red; position: relative;z-index:1;">
red
</div>

blue

red

ext js library

Firfox error message: ext is not defined

<link type="text/css" rel="stylesheet" href="/js/ext-2.2/resources/css/ext-all.css"/>
<script type="text/javascript" src="/js/ext-2.2/adapter/ext/ext-base.js"></script>
<script type="text/javascript" src="/js/ext-2.2/ext-all.js"></script>

vsftpd config

• add user

useradd -d /dir -s /sbin/nologin ftpusername
passwd ftpusername

SQL sample

1. one table join itself
select file.id from history t1, history t2, file where file.id=t1.file_id and t1.id<>t2.id and t1.updated_at=t2.updated_at and t1.ip=t2.ip and t1.file_id<>114 and t2.file_id=114 group by t1.file_id order by count(t1.file_id) desc;

URL rewrite

This summary is not available. Please click here to view the post.

Apache log setting

LogFormat "%h %l %u %t \"%r\" %>s %b" common
CustomLog logs/access_log common

<virtualhost>
ServerName xxxx
ServerAlias xxxx.com
DocumentRoot /home/www/xxxx.com/web
AddType application/x-httpd-php .php
<directory>
AllowOverride All
Order allow,deny
Allow from all
</directory>
RewriteLog /home/www/xxxx.com/log/xxxx.com_rewrite_log
RewriteLogLevel 3
ErrorLog /home/www/xxxx.com/log/xxxx.com_error_log
CustomLog /home/www/xxxx.com/log/xxxx.com_access_log common
</virtualhost>


Reference
http://httpd.apache.org/docs/1.3/logs.html

Linux system call

include/asm/unistd_32.h
arch/x86/kernel/syscall_table_32.S

#include <linux/unistd.h>
#define __NR_my_kernel_init 327

//_syscall1(int, my_kernel_init, int, debug);
int my_kernel_init(int debug)
{
return syscall(__NR_my_kernel_init, debug);
}
int main()
{
int ret = my_kernel_init(1);
printf( "%d\n", ret);
return 0;
}

when I using _syscall1(int, my_kernel_init, int, debug), I got an error:
test.c:6: error: expected declaration specifiers or ‘...’ before ‘my_kernel_init’
test.c:6: error: expected declaration specifiers or ‘...’ before ‘debug’
test.c:6: warning: data definition has no type or storage class


Reference:
Linux system call list

Kernel command using Linux system calls, Explore the SCI and add your own calls

MySql error

• Can't open file: 'xxxx.MYI' (errno: 13)

perror 13
OS error code 13: Permission denied
chmod 777 xxxx.MYI

• Repair MySql database table index file

myisamchk -r -q xxxx.MYI

• MySQL said: Documentation
  #1114 - The table 'xxxx' is full
  

table xxxx is too large

• ERROR 1030 (HY000): Got error 127 from storage engine

perror 127
MySQL error code 127: Record-file is crashed

• repair table xxx USE_FRM;

Reference
http://bbs.ylqonline.net/redirect.php?tid=332&goto=lastpost

set icon for your website

add in head part of page

<link rel="shortcut icon" href="/img/favicon.png">

not only ico file, but also png image work well.

vi config

vi ~/.vimrc

set tabstop=4
set shiftwidth=4
set nu
syntax on
set smartindent
set incsearch
set vb t_vb=

In CentOS, vim doesn't alias to vi for root (see /etc/profile.d/vim.sh)
so root must use vim directly.

set CPU frequency in Linux

• ls /sys/devices/system/cpu/cpu0/
• cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_driver etc.

scaling_available_governors: ondemand userspace performance
scaling_available_frequencies

• modprobe acpi-cpufreq
• cat /proc/cpuinfo | grep 'cpu MHz'
• cpufreq-selector
  -c, --cpu CPU Number
  -g, --governor Governor
  -f, --frequency Frequency in KHz
  
• /usr/sbin/cpuspeed -m 2000000 -M 2000000 -s 7

/etc/sysconfig/cpuspeed, configuration file
/etc/init.d/cpuspeed, initialzation script
/usr/sbin/cpuspeed, cpuspeed program

• cpufreq-set

cpufreq-set -d 2667000 -u 2667000 -c 0

• cpufreq-info
  

linux networking command

• print route table

netstat -r

• add route table entry

route add -net 172.16.2.0 netmask 255.255.255.0 gw 172.16.2.2

• restart network
  

/etc/init.d/networking restart

Build and using a new glibc

1. export LD_LIBRARY_PATH=
2. ../glibc-2.5/configure --prefix=/home/xxxx/nptl/install
3. make
4. make install
5. link to new glibc

gcc test.c -L/home/xxxx/nptl/install/lib -I/home/xxxx/nptl/install/include -static -lpthread

• modify glibc

some definition, include pthread_mutex_t etc.
glibc-2.5/nptl/sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h

some nptl function
glibc-2.5/nptl/pthread_mutex_lock.c
glibc-2.5/nptl/sysdeps/i386/pthread_spin_lock.c

cp glibc-2.5/nptl/sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h install/include/bits/pthreadtypes.h
cp build/nptl/libp* install/lib
rm build/libc.so

Assembly manual

Inline assembly for x86 in Linux

AT&T ASM Syntax

manual

set meta information for a page in Symfony

$response = $this->getResponse();
$response->setTitle($title);
$response->addMeta('keywords', $kws);
$response->addMeta('description', $desc);

get thread id

#include
#include
#include


int my_gettid()
{
int * p = (int*)pthread_self();
int pid = getpid();
assert(pid == p[19]);
return p[18];
}

int my_gettid(pthread_t thread)
{
int *p = (int*)thread;
return p[18];
}

void BusyWork(void* t)
{
int tid = my_gettid();
int pid = getpid();
printf("worker tid %d pid %d\n",tid,pid);
}

int main()
{
int tid = my_gettid();
int pid = getpid();
printf("main tid %d pid %d\n",tid,pid);

pthread_t thread;
pthread_create(&thread, NULL, BusyWork, NULL);

pthread_join(thread,NULL);
return 0;
}

pthread spin lock in glibc nptl

• The Glibc I using is glibc-2.5, computer architecture is i386

• type definition of pthread_spinlock_t
  

nptl/sysdeps/unix/sysv/linux/i386/bits/pthreadtypes.h
/* POSIX spinlock data type. */
typedef volatile int pthread_spinlock_t;

• function pthread_spin_lock

nptl/sysdeps/i386/pthread_spin_lock.c

• my test of spin lock

#include
#include

#define NUM_THREADS 8
long sum;
pthread_spinlock_t sumlock;

int my_sleep(int i)
{
int j,k,n=0;
for(;i>0;i--)
for(j=0;j<100;j++)
for(k=0;k<100;k++)
n++;
return n;
}

void *BusyWork(void *threadid)
{
int i,k;
long tid = (long)threadid;
for(i=0;i<10;i++){
k = my_sleep(3);
pthread_spin_lock (&sumlock);
printf("%d ", tid);
sum += k;
pthread_spin_unlock (&sumlock);
}
pthread_exit((void *) 0);
}

int main (int argc, char *argv[])
{
pthread_t thread[NUM_THREADS];
int rc, t;
void *status;
pthread_spin_init(&sumlock, NULL);
for(t=0; t
rc = pthread_create(&thread[t], NULL, BusyWork, (void*)t);
if (rc){
return 0;
}
}
for(t=0; t
rc = pthread_join(thread[t], &status);
if (rc){
printf("ERROR; return code from pthread_join() is %d\n", rc);
return 0;
}
}
printf("sum = %ld\n", sum);
pthread_spin_destroy(&sumlock);
pthread_exit(NULL);
}

Bind a thread/process to a CPU core

#include <sched.h>

• Bind the invoke thread to a CPU core which id is p

void thread_bind(int p)
{
cpu_set_t mask;
__CPU_ZERO(&mask);
__CPU_SET(p, &mask);
sched_setaffinity(0, sizeof(mask), &mask);
}

• Bind thread which id is tid to a CPU core p
  

void thread_bind(int p, int tid)
{
cpu_set_t mask;
__CPU_ZERO(&mask);
__CPU_SET(p, &mask);
sched_setaffinity(tid, sizeof(mask), &mask);
}

Reference

1. Get thread id

Add a /proc/ file using Linux kernel module

Reference
1. Create a Linux Module
2. http://www.ibm.com/developerworks/linux/library/l-proc.html

vi command

1. full text replacement
:1,$s/tom/David/g
from first line to last line, replace tom with David

Search in Linux

grep -R xxxx .

Create a Linux module

1. vi simple-lmk.c

#include 

/* Defines the license for this LKM */
MODULE_LICENSE("GPL");

/* Init function called on module entry */
int my_module_init( void )
{
printk(KERN_INFO "my_module_init called.  Module is now loaded.\n");
return 0;
}

/* Cleanup function called on module exit */
void my_module_cleanup( void )
{
printk(KERN_INFO "my_module_cleanup called.  Module is now unloaded.\n");
return;
}

/* Declare entry and exit functions */
module_init( my_module_init );
module_exit( my_module_cleanup );

2. vi Makefile

obj-m += simple-lkm.o

3. build

make -C /usr/src/linux-`uname -r` SUBDIRS=$PWD modules

4. insert module
insmod simple-lkm.ko

5. check module
lsmod

6. check print message
dmesg | tail -5

7. remove module
rmmod simple-lkm
 

Connect VMware client from Linux host

I setup a Linux virtual machine on a Linux host, using NAT network.
When connect from virtual machine to host, it is successful. But there is a problem from host connect to virtual machine, the error message of ping is:
ping sendmsg operation not permitted

There need set an port mapping of NAT.
In host Linux, edit configure file /etc/vmware/vmnet8/nat/nat.conf
add one line "2222 = 192.168.27.128:22" under [incomingtcp]
192.168.27.128 is IP of virtual machine.

Then reboot

ssh -l root -p 2222 localhost
will telnet to virtual machine from host Linux.

Reference
1. http://www.vmware.com/support/ws55/doc/ws_net_nat_advanced.html

build and install a new Linux kernel

1. Down load a new linux kernel from http://www.kernel.org/
2. cp /boot/config-xxx .config
3. make
4. make modules_install install
5. reboot