Bookmarks for 27 lug 2012 through 30 lug 2012

These are my links for 27 lug 2012 through 30 lug 2012:

  • Rex V: an AJAX Regular EXpression eValuator - – This site is a Regular Expression evaluator for several different regular expression systems:
    PHP PCRE
    PHP Posix
    Perl
    Python
    Javascript
    Node.JS
  • calligrafia.org » il sito dell’Associazione Calligrafica Italiana – [...] Nel settembre 1991 a Milano, un gruppo di calligrafi fonda l'Associazione calligrafica Italiana. Da allora il programma dell'Associazione è cresciuto con successo anche grazie ai contatti mantenuti con altre associazioni calligrafiche all'estero (in Europa e in America) garantendo così scambi di informazioni e soprattutto la possibilità di avvalersi della collaborazione di insegnanti di riconosciuta competenza. In questi anni l'ACI ha sicuramente ottenuto successi e risultati. Oramai la calligrafia è praticata anche in Italia, sono state organizzate mostre e avviati contatti con biblioteche e scuole[...]
  • Rajiv’s blog – I was in charge of scaling Dropbox for a while, from roughly 4,000 to 40,000,000 users. For most of that time we had one to three people working on the backend. Here are some suggestions on scaling, particularly in a resource-constrained, fast-growing environment that can’t always afford to do things “the right way” (i.e., any real-world engineering project ;-). If people find this useful, I’ll try to come up with more tips and write a part 2.

Bookmarks for 25 lug 2012 from 14:52 to 15:47

These are my links for 25 lug 2012 from 14:52 to 15:47:

  • Disaster: LVM Performance in Snapshot Mode – MySQL Performance Blog – In many cases I speculate how things should work based on what they do and in number of cases this lead me forming too good impression about technology and when running in completely unanticipated bug or performance bottleneck. This is exactly the case with LVM
    Number of customers have reported the LVM gives very high penalty when snapshots are enabled (leave along if you try to run backup at this time) and so I decided to look into it.
  • Netexpertise » Mysql Ultra-Fast Backup with LVM – It is generally good practice to respect the two following points when backing up databases. The backup has to be:
    consistent
    fast
    Consistency is easily achieved putting a read lock on all tables beforehands. However, this isn’t always applied, and WILL definately lead to a database integrity problem at some stage.
    Once a lock has been set on the database, the backup has to be as quick as possible, all write instructions being held in the queue.
  • MIME and HTML in Email – How to encapsulate HTML in an email message and send via sendmail

Bookmarks for 24 lug 2012 from 17:16 to 17:32

These are my links for 24 lug 2012 from 17:16 to 17:32:

  • Five Tips for a Better sendmail Configuration – O’Reilly Media – Unix vendors bundle sendmail with the operating system and ship it out preconfigured. It is very easy to install the OS and use the sendmail configuration delivered with the system. Don't be fooled by this apparent simplicity. In the long run, it is better to take charge of your fate. Creating a custom sendmail configuration using current software and features selected for your environment will give you better performance, reliability, security, and maintainability. Here are some tips to get you started on building a better sendmail configuration.
  • Epoch Converter – Unix Timestamp Converter – Epoch & Unix Timestamp Conversion Tools
  • mylvmbackup – mylvmbackup is a tool for quickly creating backups of a MySQL server's data files. To perform a backup, mylvmbackup obtains a read lock on all tables and flushes all server caches to disk, creates a snapshot of the volume containing the MySQL data directory, and unlocks the tables again. The snapshot process takes only a small amount of time. When it is done, the server can continue normal operations, while the actual file backup proceeds.

Bookmarks for 18 lug 2012 through 19 lug 2012

These are my links for 18 lug 2012 through 19 lug 2012:

  • Generate large amount of test data « my two cents – I’m using the dictionary on linux systems to generate test data. The shell script below generates test data for MySQL, but similar concepts can be used for other database systems as well.
  • JQueryin | Switching Apache from Prefork to Worker MPM in RHEL / CentOS 5.x / Fedora 13 – I’m going to outline the process of switching from Apache’s default installation of MPM Prefork to that of MPM Worker. I will also be covering the proper installation of FastCGI (mod_fcgid) to further improve your server performance. This guide is ideally intended for individuals running on low-memory VPS servers as memory consumption will likely be far lower with the Worker MPM because it spawns threads as opposed to forking child processes. If you’re intentionally reading this article, you’re probably aware of the performance benefits gained.
  • Free PDF Reader – Sumatra PDF – Sumatra PDF is a free PDF, eBook (ePub, Mobi), XPS, DjVu, CHM, Comic Book (CBZ and CBR) reader for Windows.

    Sumatra PDF is small, portable and starts up very fast.

    Simplicity of the user interface has a high priority.