PostgreSQL, Rails and Heroku

rails new blog -d postgresql

The performance of SAMSUNG 830 Series 2.5-Inch 256GB on Mountain Lion

Here is the result from Xbench:


Results 565.10
System Info
Xbench Version 1.3
System Version 10.8 (12A269)
Physical RAM 8192 MB
Model MacBookPro8,2
Drive Type SAMSUNG SSD 830 Series
Disk Test 565.10
Sequential 374.59
Uncached Write 593.36 364.31 MB/sec [4K blocks]
Uncached Write 598.18 338.45 MB/sec [256K blocks]
Uncached Read 164.58 48.17 MB/sec [4K blocks]
Uncached Read 803.01 403.59 MB/sec [256K blocks]
Random 1149.93
Uncached Write 847.69 89.74 MB/sec [4K blocks]
Uncached Write 967.11 309.61 MB/sec [256K blocks]
Uncached Read 2547.83 18.05 MB/sec [4K blocks]
Uncached Read 1146.40 212.72 MB/sec [256K blocks]

After trim enabler:


Results 563.27
System Info
Xbench Version 1.3
System Version 10.8 (12A269)
Physical RAM 8192 MB
Model MacBookPro8,2
Drive Type SAMSUNG SSD 830 Series
Disk Test 563.27
Sequential 373.48
Uncached Write 583.23 358.09 MB/sec [4K blocks]
Uncached Write 596.24 337.35 MB/sec [256K blocks]
Uncached Read 164.58 48.17 MB/sec [4K blocks]
Uncached Read 804.85 404.51 MB/sec [256K blocks]
Random 1145.28
Uncached Write 1268.14 134.25 MB/sec [4K blocks]
Uncached Write 705.85 225.97 MB/sec [256K blocks]
Uncached Read 2562.21 18.16 MB/sec [4K blocks]
Uncached Read 1114.80 206.86 MB/sec [256K blocks]


Almost the same, as expected.

HOWTO: use pathogen to manage vim plugins

I am now using pathogen and GitHub to manage my vim plugins.
They are not difficult to use, but you need a few git commands to set it up, which I found very annoying.

To init .vim folder in Linux (or vimfiles for Windows), type:


mkdir .vim
cd .vim
git init
wget https://raw.github.com/tpope/vim-pathogen/HEAD/autoload/pathogen.vim -P ~/.vim/autoload
git add .
git commit -m 'initial commit'


To install each vim plugin, type: (here I use neocomplcache-snippets-complete as an example)


git submodule add https://github.com/Shougo/neocomplcache-snippets-complete.git bundle/neocomplacahe-snippets-complete
git add .gitmodules bundle/neocomplcache-snippets-complete
git submodule init


iOS errors

/* FoundationErrors.h

Copyright (c) 2004-2011, Apple Inc. All rights reserved.

*/

#import <Foundation/NSObject.h>

/* NSError codes in NSCocoaErrorDomain. Note that other frameworks (such as AppKit and CoreData) also provide additional NSCocoaErrorDomain error codes.

*/

enum {

    // File system and file I/O related errors, with NSFilePathErrorKey or NSURLErrorKey containing path or URL

    NSFileNoSuchFileError = 4,     // Attempt to do a file system operation on a non-existent file

    NSFileLockingError = 255,     // Couldn't get a lock on file

    NSFileReadUnknownError = 256,                           // Read error (reason unknown)

    NSFileReadNoPermissionError = 257,                      // Read error (permission problem)

    NSFileReadInvalidFileNameError = 258,                   // Read error (invalid file name)

    NSFileReadCorruptFileError = 259,                       // Read error (file corrupt, bad format, etc)

    NSFileReadNoSuchFileError = 260,                        // Read error (no such file)

    NSFileReadInapplicableStringEncodingError = 261,        // Read error (string encoding not applicable) also NSStringEncodingErrorKey

    NSFileReadUnsupportedSchemeError = 262,     // Read error (unsupported URL scheme)

#if MAC_OS_X_VERSION_10_5 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_2_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED

    NSFileReadTooLargeError = 263,     // Read error (file too large)

    NSFileReadUnknownStringEncodingError = 264,     // Read error (string encoding of file contents could not be determined)

#endif /* MAC_OS_X_VERSION_10_5 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_2_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED */

    NSFileWriteUnknownError = 512,     // Write error (reason unknown)

    NSFileWriteNoPermissionError = 513,                     // Write error (permission problem)

    NSFileWriteInvalidFileNameError = 514,                  // Write error (invalid file name)

#if MAC_OS_X_VERSION_10_7 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_5_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED

    NSFileWriteFileExistsError = 516,     // Write error (file exists)

#endif

    NSFileWriteInapplicableStringEncodingError = 517,       // Write error (string encoding not applicable) also NSStringEncodingErrorKey

    NSFileWriteUnsupportedSchemeError = 518,     // Write error (unsupported URL scheme)

    NSFileWriteOutOfSpaceError = 640,                       // Write error (out of disk space)

#if MAC_OS_X_VERSION_10_6 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_4_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED

    NSFileWriteVolumeReadOnlyError = 642,     // Write error (readonly volume)

#endif

    // Other errors

    NSKeyValueValidationError = 1024,                       // KVC validation error

    NSFormattingError = 2048,                               // Formatting error

    NSUserCancelledError = 3072,     // User cancelled operation (this one often doesn't deserve a panel and might be a good one to special case)

    

#if MAC_OS_X_VERSION_10_5 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_2_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED

    // Executable loading errors

    NSExecutableNotLoadableError = 3584,                    // Executable is of a type that is not loadable in the current process

    NSExecutableArchitectureMismatchError = 3585,           // Executable does not provide an architecture compatible with the current process

    NSExecutableRuntimeMismatchError = 3586,                // Executable has Objective C runtime information incompatible with the current process

    NSExecutableLoadError = 3587,                           // Executable cannot be loaded for some other reason, such as a problem with a library it depends on

    NSExecutableLinkError = 3588,                           // Executable fails due to linking issues

#endif /* MAC_OS_X_VERSION_10_5 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_2_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED */

    

    // Inclusive error range definitions, for checking future error codes

    NSFileErrorMinimum = 0,

    NSFileErrorMaximum = 1023,

    

    NSValidationErrorMinimum = 1024,

    NSValidationErrorMaximum = 2047,

#if MAC_OS_X_VERSION_10_5 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_2_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED

    NSExecutableErrorMinimum = 3584,

    NSExecutableErrorMaximum = 3839,

#endif /* MAC_OS_X_VERSION_10_5 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_2_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED */

    NSFormattingErrorMinimum = 2048,

    NSFormattingErrorMaximum = 2559,

    

#if MAC_OS_X_VERSION_10_6 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_4_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED

    NSPropertyListReadCorruptError = 3840,                  // Error parsing a property list

    NSPropertyListReadUnknownVersionError = 3841,           // The version number in the property list is unknown

    NSPropertyListReadStreamError = 3842,                   // Stream error reading a property list

    NSPropertyListWriteStreamError = 3851,                  // Stream error writing a property list

    NSPropertyListErrorMinimum = 3840,

    NSPropertyListErrorMaximum = 4095

#endif /* MAC_OS_X_VERSION_10_6 <= MAC_OS_X_VERSION_MAX_ALLOWED || __IPHONE_4_0 <= __IPHONE_OS_VERSION_MAX_ALLOWED */

    

};

How To: Install TouchXML for ios

1. download TouchXML from github
2. add the sources to your project
3. In project->build settings->header search paths:
add /usr/include/libxml2
4. In project->targets->build phases->link library with binaries:
add "libxml2.2.7.3.dylib"

How To: Install lxml on Ubuntu

sudo apt-get install libxml2-dev
sudo apt-get install libxslt1-dev
sudo apt-get install python2.6-dev
easy_install --allow-hosts=lxml.de,*.python.org lxml

List of commands for MySql and Django

mysqladmin.exe -u root -p create myapp
python manage.py syncdb
mysql -u root -p
sudo /etc/init.d/apache2 restart

OpenSSH configuration file

Putty is a lovely ssh program, but I love console2 even more.

To use ssh to connect to Amazon EC2 server, you need cygwin to run openssh in Windows environment.
The command is (under cygwin):

ssh -i MySite.pem ubuntu@xxx.amazonaws.com
To make the command shorter, create "~/.ssh/config"
and add:

Host MySite
User ubuntu
Port 22
IdentityFile ~/.ssh/MySite.pem
HostName xxx.amazonaws.com
To connect, just type:

ssh MySite

Setting selective sync of Dropbox on Amazon EC2 server

Dropbox provides an easy to backup the server. However, the default setting synchronizes all of the files to the server, which is very annoying.
I don't want all of my personal stuff to be stored in a public server.

In order to select the file which you would like to sync, download dropbox.py
and type the following commands in the terminal:
python dropbox.py exclude add ~/Dropbox/*
python dropbox.py exclude remove ~/Dropbox/<folder-to-sync> 
The first command excludes all of files from your dropbox.
The second one adds the folder which is going to be synchronized.

Setting up Django on ubuntu

Here are the steps to setup Django on Amazon EC2 server:

The image is ubuntu-maverick-10.10-amd64-server-20101225

Choose the ebs one, otherwise you will lose everything after you shutdown your server

1. sudo apt-get update
2. sudo apt-get install apache2
3. wget http://www.djangoproject.com/download/1.3/tarball/
4. mv index.html Django-1.3.tar.gz
5. tar xzvf Django-1.3.tar.gz
6. cd Django-1.3
7. sudo python setup.py install
8. sudo  apt-get install libapache2-mod-wsgi
9. create "/home/ubuntu/mysite/django-server.wsgi"
import os, sys
sys.path.append('/home/ubuntu/')
sys.path.append('/home/ubuntu/mysite')
os.environ['DJANGO_SETTINGS_MODULE'] = 'mysite.settings'
import django.core.handlers.wsgi
application = django.core.handlers.wsgi.WSGIHandler()

10. sudo /etc/init.d/apache2 start
11. cd  /etc/apache2/sites-available
12. sudo cp  default mysite
13. edit "mysite"
Listen 8000
<VirtualHost *:8000>
        WSGIScriptAlias / /home/ubuntu/mysite/django-server.wsgi
        WSGIDaemonProcess server1piece user=www-data group=www-data processes=1 threads=10
        ServerAdmin webmaster@localhost
        DocumentRoot /home/ubuntu/
        Alias /static/admin/ /home/ubuntu/Django-1.3/django/contrib/admin/media/
14. a2ensite mysite
15. sudo /etc/init.d/apache2 reload
16. sudo /etc/init.d/apache2 restart
17. cd ~
18. django-admin startproject mysite
19. cd ~/mysite
20. django-admin startapp myapp 
21. python manage.py runserver 0.0.0.0:8000