Author: admin

Able to display the qemu screen in GKD

I use Tightvnc java library to display the qemu screen in GKD. The tightvnc java library is able to display in a JFrame/JApplet, but not in a JPanel, so I modified it to make it work in a JPanel, all the code is in , take a look the function initVNCPanel() read count : 363


2013/05/21 0

example launch the vnc by tightvnc java library

After a few hours hack into the tightvnc code, i can display the vnc onto a JPanel, i will replace the buggy novnc with my own vnc proxy server, so user don’t need to setup the novnc for openstack but able to remote to every instance using openstack. PeterIPasswordRetriever.java: read count : 1066


2013/05/20 0

tightvnc java viewer, cancel connection dialog popup

when running tightvnc java viewer, add parameter “-password=mypassword myhost:9401” change line 181 in Viewer.java, from to read count : 475


2013/05/19 0

The script i use to restart the devstack

This is the script i use to restart the devstack, i am using it with ubuntu 12.10 64 bits and devstack restart_devstack.sh read count : 705


2013/05/17 0

Samsung galaxy s4, charging the battery, using samsung USB cable is much faster

Samsung galaxy s4, charging the battery, using samsung USB cable is much faster than third-party usb cable, here is my test 1) samsung power adapter + samsung usb cable, charge from 10% to 30% takes 20 minutes 2) samsung power adapter + third-party 3M-long usb cable, charge from 10% to 30% takes 1 hour and 15…
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2013/05/13 1

converted LibGKD to maven project

converted LibGKD to maven project, because peter-swing is now a maven project, better to convert it too read count : 386


2013/05/12 0

openstack token expiry date

my colleague Thomas discovered that if we send two commands to openstack using the curl to get the same token, the expiry will keep changing to later time. This will cause the token never expire. read count : 645


2013/05/07 0

peter-dwarf can support 32 bits elf only

There is a western friend told me he can’t use peter-dwarf to parse his 64 bits elf file, after i trace my code, i finally found my peter-dwarf library only support 32 bits elf. I need some time to enhance it and make it 64 bits. read count : 486


2013/04/26 2

something need to care when you use devstack

I have a ubuntu 12.10 64 bits, i can easily install devstack, but there are some points still need to care about the devstack 1. Devstack installation script is to git clone the latest version from the openstack source repository, if the repository’s code contain bug, your openstack will fail. If you use devstack in…
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2013/04/24 1

steps to reinstall devstack

steps to reinstall devstack 1) Remove all the openstack;s databases from mysql, glance, keystone, nova, etc… 2) Delete the install directory of devstack, default is /opt/stack 3) Remove your old devstack git clone directory, because we want to check out the latest code 4) You *don’t* need to delete /usr/local/lib/python2.7/distpackages/openstack* , but if you did…
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2013/04/22 4

let’s beat vSphere using openstack

Let’s beat vSphere using openstack, first step is to learn everything from it o VMware vSphere 5 Evaluation Guide – Volume1 VMware-vSphere-Evaluation-Guide-1 o VMware vSphere 5 Evaluation Guide – Volume 2 – Advance Storage Features VMware-vSphere-Evaluation-Guide-2-Advanced-Storage o VMware vSphere 5 Evaluation Guide – Volume 3 – Advance Networking Features VMware-vSphere-Evaluation-Guide-3-Advanced-Networking o VMware vSphere 5 Evaluation…
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2013/04/17 0

A very professional ppt that talk about system performance tuning

A very professional ppt that talk about system performance tuning download : scalelinuxperformance-130224171331-phpapp01 read count : 559


2013/04/17 0

development openstack dashboard

I and my colleague are currently develop some modules on openstack dashboard. Here is the list for you to know : when you modify a page in dashboard, which files you need to deal with, this will save you some time: download : openstack_dashboard read count : 1325


2013/04/12 0

openstack – restart error : Max retries exceeded with url

If you install openstack by devstack, when you reboot your server and restart the openstack by this script http://www.scalegrid.net/blog/?p=52, when you browse to the dashboard and you will see this error message “HTTPConnectionPool(host=’192.168.100.170′, port=8776): Max retries exceeded with url: /v1/b721f5b1f7cd43dd83ee573f6d4e6c74/os-quota-sets/b721f5b1f7cd43dd83ee573f6d4e6c74 (Caused by <class ‘socket.error’>: [Errno 111] Connection refused)” You should check with your endpoints server…
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2013/04/09 0

Openstack architecture diagram (kvm, qemu-kvm, libvirt, nova, cinder)a

Correct me if i am wrong. Openstack components (nova, cinder, glance) controls libvirt to provide visualization and libvirt use qemu-kvm as the hypervisor. The reason openstack don’t control the qemu-kvm directly is because libvirt provides better cross VM functionality (it can adopt to xen, vmware, etc…) and it provides high-end function such pool management and…
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2013/03/29 0

put python+django to apache through virtualhost

to put python+django to apache through virtualhost 1) edit /etc/httpd/conf/httpd.conf 2) edit /root/workspace/MyDjangoProject/P1/wsgi.py, change it to read count : 537


2013/03/26 0

error in manage.py createsuperuser

error in manage.py createsuperuser To solve the above issues, type in read count : 479


2013/03/26 0

GDB will remove all breakpoint and set it back repeatly

When you set the breakpoint by input the “b” command, the gdb will not set it immediately, it will wait until the user pressed “c” to cont execute the program. After you pressed “c”, gdb will set all the breakpoints for you. The most funny thing is : when gdb hit a breakpoint and gain…
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2013/03/23 0

qemu debug server hang after breakpoint is hit

If you are developing a debug server for qemu, after qemu hit a breakpoint, your server have to remove the breakpoint manually and re-insert it after the cpu passed that EIP, otherwise the cpu will forever stay in the EIP and can’t single-step/cont to the next instruction. If you take a look the gdbstub.c, gdb…
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2013/03/21 0

QEMU migration via QMP / Monitor command

I just tested the qemu-kvm with QMP, when i send out the qmp command for migration, it takes 20 seconds, it is much slower than type in the command in qemu monitor. read count : 451


2013/03/21 0

How to use QMP, send command remotely to qemu

To use qmp and send command to qemu from another process, start qemu by This will create a file /tmp/test.gmp for interchange the command. Then you can start another terminal and invoke command.txt: !!! remark, must invoke { “execute”: “qmp_capabilities” } before invoke any qmp command read count : 1358


2013/03/20 1

openstack conflict with virtualbox

When you are running vm in virtual box, and try to start any vm in openstack. The vm that are running in virtualbox will crash immediately, you need to do the follow command to shut it down. If you want to restart that VM, please rmmod the kvm module. I guess is that the kvm…
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2013/03/17 0

OOM has trouble to KVM, it can’t shot down the kvm

In Linux, if the system is out of memory, OOM will pick one process to kill. But someone reported the OOM can’t kill the qemu-kvm, that mean if you are running many VMs that eat up all the memory, the Linux will hang because OOM can’t kill them In tried to run 64 VMs using…
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2013/03/17 0

Restructuring the debugger

At the moment, i am facing 2 big problems of bochs, the first one is unsolvable, bochs running too slow. It is ok if you are doing a hobby OS development, but if you are trying to use bochs to run a full feature Linux kernel or a windows 7, it is just so slow.…
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2013/03/13 0

add 1440×900 resolution to vnc

read count : 7108


2013/03/07 0

qemu single step will fail if current EIP hit a breakpoint

I use the following code to insert a breakpoint in physical address 0x1600000 qemu successfully hit the breakpoint and stop, then i try to single-step by the following code: Nothing happened, the EIP still stay in 0x1600000, but if i delete the breakpoint, the single step just work again. Am I missed something? read count…
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2013/02/14 0

when you debugging qemu, it will keep firing SIGUSR1 so gdb will always catched in some breakpooints that are not defined by you

when you debugging qemu, it will keep firing SIGUSR1 so gdb will always catched in some breakpooints that are not defined by you, to turn off the SIGUSR1, you have to: (gdb) info signal SIGUSR1 Signal Stop Print Pass to program Description SIGUSR1 Yes Yes Yes User defined signal 1 And if deemed to not…
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2013/02/12 0

linker script offset seems crazy

linker script offset seems crazy, take a look the following two pictures   read count : 525


2013/02/09 0

compile grub2 : error: ‘gets’ undeclared here

if you compile grub2 , you may get “error: ‘gets’ undeclared here yum”, to fix it, run the following command: sed -i -e ‘/gets is a security/d’ grub-core/gnulib/stdio.in.h   read count : 1194


2013/02/09 0

compile 64 bits newlib on 64 bits linux host

If you compile newlib in x86-64 host and want to have 64-bits newlib, you have to add “–disable-multilib“, otherwise you will get the following error: read count : 731


2013/02/03 0

PSI probe for tomcat can’t generate chart

Add this “CATALINA_OPTS=-Djava.awt.headless=true” to catalina.sh read count : 275


2013/01/31 0

newlib compile error in Fedora 18 64 bits

when you meet the following error, add “.code32” can fix it. ../../../../../../newlib-1.19.0/newlib/libc/machine/i386/memcmp.S: Assembler messages: ../../../../../../newlib-1.19.0/newlib/libc/machine/i386/memcmp.S:18: Error: invalid instruction suffix for `push’ ../../../../../../newlib-1.19.0/newlib/libc/machine/i386/memcmp.S:21: Error: invalid instruction suffix for `push’ ../../../../../../newlib-1.19.0/newlib/libc/machine/i386/memcmp.S:22: Error: invalid instruction suffix for `push’ ../../../../../../newlib-1.19.0/newlib/libc/machine/i386/memcmp.S:23: Error: invalid instruction suffix for `push’ ../../../../../../newlib-1.19.0/newlib/libc/machine/i386/memcmp.S:72: Error: invalid instruction suffix for `pop’ ../../../../../../newlib-1.19.0/newlib/libc/machine/i386/memcmp.S:73: Error: invalid instruction suffix for…
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2013/01/30 0

10 places where anyone can learn to code

Teens, tweens and kids are often referred to as “digital natives.” Having grown up with the Internet, smartphones and tablets, they’re often extraordinarily adept at interacting with digital technology. But Mitch Resnick, who spoke at TEDxBeaconStreet in November, is skeptical of this descriptor. Sure, young people can text and chat and play games, he says, “but that…
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2013/01/30 1

In search of the anti-ddos device

http://dev.esl.eu/blog/2010/09/10/in-search-of-the-anti-ddos-device/ Preamble The following text describes the evaluation of the most reasonable solution in order to achieve the goal of protecting our infrastructure from DDoS attacks. All collected values and impressions do not lay claim to being correct nor complete. This article only reflects our experiences and data and therefore should be used to help…
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2013/01/21 0

Fix the PermGen error in tomcat

Fix the PermGen error in tomcat, execute this before startup.sh: export JAVA_OPTS=”-XX:PermSize=2048m” read count : 256


2013/01/15 0

Ported ubuntu theme to fedora

Ported ubuntu theme to fedora, tested on FC17, unzip themes.tar.bz2 in /usr/share/themes read count : 260


2013/01/04 0

A x86 java disassembler from Maxine Project

I have been asking for a java x86 disassembler library for a long time, i finally found “Maxine” project from oracle, it is a VM project with built-in a x86 assembler written Java. I git-ed the source and compile them in eclipse, it works!, here is the source and screenshot. source : maxine_disassembler read count…
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2012/12/27 0

Lowest 7 levels of /lib, /bin, /usr/bin, /usr/lib

No recursive /bin /lib /usr/bin /usr/lib read count : 368


2012/12/24 0

Peter-bochs – State chart diagram

read count : 380


2012/12/22 0

How to change Fedora’s font rendering to get an Ubuntu-like result

Font rendering is a matter of taste. However, I personally think Ubuntu’s default font rendering is the most eye-pleasing one of the whole Linux eco-system. And if a website’s CSS font stack is looking good on Ubuntu, you can be relatively sure that it also works for Mac or MS Windows as long as the used fonts are available on these…
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2012/12/13 4