Oh, and when adding methods to core classes...

There's this neat pattern of checking to see if it's there first. I'm not sure if this really saves any cycles (I would imagine a few), but may aid in avoiding collisions, at the very least. For example thus:

unless String.instance_methods.include? "_sp_clean"
  class String
    def _sp_clean
      str = self.clone
      str = CGI.escape(str) # Turns spaces into '+' rather than '%20'... we expect that, though
                            # URI.escape allows [=&], etc... which we don't want.
    end
  end
end

...Now I hope that formats nicely when this message posts. : \

Built my first gem

...And it was rather easy.  After using the "newgem" gem to create the skeleton, I just followed some bloke's instructions for editing the Rakefile.  Piece of cake.

Just thought I'd mention it.

Text and HTML in Thunderbird

So, I'm using Thunderbird now.

One of the first pains that I've encountered is that, when replying to email, I get a warning that HTML may be unavailable to the recipient.

To turn this warning off (and select whatever you want as a default), look under Tools > Options > Composition > Send Options.  The rest should be self-explanatory.

Learning

Wow, what a blast these past three days have been!  We had a consultant in from MySQL, and I learned hoards of new tricks, tips, and techniques.  Here are a few:

• You can store images on the filesystem based on their PK, to save having a field with the path.  For example, image.id = 15579, image.path = images/1/5/5/7/9.png (or whatever level of separation you find appropriate).
• EXT3--though it can be tuned--is not an ideal filesystem for databases.  XFS is much better.  (He didn't give specific reasons, and I don't particularly care to look into it.)
  
• QCache_hits should be much higher than QCache_inserts.  (show with "show global status like 'qc%'")  If it's not, you need to hard-code which queries use the cache and which don't.  Global status can also tell you about the number of locks that are occurring, which you may also wish to tweak.
  
• query_cache_type values are: 0 = off, 1 = on, 2 = on demand
• QCache hits are never logged.  That would take more time.  So if you want to really see how often queries are running, you have to turn of caches.
• 400M is a reasonable limit for query cache.
• Stop apache from forking: this is what brings so many sites down.  Instead, figure out how many concurrent processes your box can really handle, and then set the number of connections to this limit. If this is exceeded, the OS will queue additional requests, and keep the system from dying.  100 is a reasonable place to start.
• MyISAM tables are fine if you're read-only (or nearly so): they will be faster.  But InnoDB is much, much faster, since they store the table completely in memory.  Of course, this means you have to have enough memory to fit the damned thing.  ; )  ...And, of course, there are caveats about very large fields (like blobs, texts, and varchars with large average size).  Shrinking your data as much as possible is important with large datasets... even one unused byte becomes a Meg with a million rows!
  
• "show innodb status\g" is a tool for checking InnoDB performance.
• strace shows all the system calls used for a command (linux).  Very cool!  Not sure how I hadn't seen this one before...
  
• Sharding is what massive scaling is all about... but that's a topic you'll have to look up on the web, since there's so much to it.  ; )

One more Annoyance with Tiger Terminal

...So, when I moved .bashrc to .bash_profile, I lost my PATH environment variable.  (Rather, it was stripped down to next to nothing.)

To fix this, I moved .bash_profile aside, re-ran terminal, ran env to get the old PATH, and pasted that into my .bash_profile where I used to say "$PATH".  Something like this:

export PATH=/sw/bin:/sw/sbin:$GEM_HOME/bin:/opt/local/bin:/usr/local/bin:/opt/local/sbin:/usr/local/mysql/bin:/Users/cpr4cpu/bin:/bin:/sbin:/usr/bin:/usr/sbin:/usr/X11R6/bin

...Pain in the arse, this.

Bash Profile, not BashRC

Another lesson learned:

In Tiger, the Terminal doesn't used .bashrc.  Why?  Couldn't say.

Just move your .bashrc file to .bash_profile

Problem solved.  Lame.  There's more discussion about this on the Mac site, but I didn't really care to dig past the workaround.

gVIM

I've spent the past couple of days setting up my Mac for Rails development. I'm still running Tiger, which is problematic (to say the least)... I hear that Leopard is all set up correctly, but I'm stuck for the time being.

I finally gave up on Aptana, which was just screwing up left and right.  ...This means that I need to fall back to my old friend, Vim. 

There's a script for calling gvim from a terminal, but I also wanted to change the color scheme on load (because my terminal is dark-on-light and my .vimrc colors are customized for that).  To accomplish this, add to your .gvimrc:

colorscheme desert

(Or whatever other scheme you care for.)

This was surprisingly difficult to find (why?!?), so... I hope you stumbled on this page before too much extra work.  ; )