A quick research showed that Mac OS X 10.6 (Snow Leopard) uses 32-bit kernel by default. This limits the applications to use only 4 GB of memory. In order for the applications to use larger memories, one need to use the 64-bit kernel (provided that you are on a 64-bit platform). There is an Apple support page that describes how to select the desired kernel.

I changed the defaults to use 64-bit kernel.

$ sudo systemsetup -setkernelbootarchitecture x86_64

This configuration is stored in the file /Library/Preferences/SystemConfiguration/com.apple.Boot.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
        <key>Kernel Architecture</key>
        <string>x86_64</string>
        <key>Kernel Flags</key>
        <string></string>
</dict>
</plist>

After making this change and rebooting, VirtualBox was able to see the whole memory.

I discovered about Org-Mode a couple of years ago. Since then, I have started using it for various tasks. One of the recent usage is to track my daily weight. This article describes how to use Org-Mode and Gnuplot to plot your weight measurements.

Here is the list of software that I use in my setup.

• Mac OS X 10.6
• GNU Emacs 23.3.1
• Org-Mode 7.5
• Gnuplot 4.4
• Gnuplot mode 0.6.0

For the purpose of this article, it is assumed that you have a similar setup that works for you.

As part of my daily measurement, I track three measurements namely, weight, body fat percentage and body water percentage. This data can be represented in an Org table that has four columns as follows. Please note that the data provided below is hypothetical.

#+PLOT: script:"Weight.plt"
| Date       | Weight |  BF% |  BW% |
|------------+--------+------+------|
| 05/01/2011 |  145.2 | 30.3 | 50.3 |
| 05/02/2011 |  145.1 | 29.4 | 50.7 |
| 05/03/2011 |  144.2 | 30.1 | 50.4 |
| 05/04/2011 |  144.0 | 29.0 | 50.8 |
| 05/05/2011 |  144.1 | 28.7 | 51.0 |
| 05/06/2011 |  144.2 | 29.2 | 50.7 |
| 05/07/2011 |  144.4 | 27.8 | 51.4 |
| 05/08/2011 |  143.7 | 27.6 | 51.5 |
| 05/09/2011 |  143.2 | 28.5 | 51.0 |
| 05/10/2011 |  142.8 | 30.1 | 50.4 |
| 05/11/2011 |  142.2 | 30.1 | 50.4 |
| 05/12/2011 |  142.4 | 29.8 | 50.5 |
| 05/13/2011 |  142.2 | 29.9 | 50.5 |
| 05/14/2011 |  141.2 | 27.4 | 51.6 |
| 05/15/2011 |  141.5 | 27.2 | 51.7 |
|------------+--------+------+------|
| 05/16/2011 |  141.2 | 28.8 | 51.0 |
| 05/17/2011 |  140.8 | 28.9 | 50.9 |
| 05/18/2011 |  140.2 | 29.5 | 50.7 |
| 05/19/2011 |  140.5 | 26.8 | 51.9 |
| 05/20/2011 |  140.4 | 28.1 | 51.3 |
| 05/21/2011 |  139.2 | 26.7 | 51.9 |
| 05/22/2011 |  137.1 | 27.0 | 51.7 |
| 05/23/2011 |  137.5 | 27.0 | 51.7 |
| 05/24/2011 |  137.4 | 28.5 | 51.1 |
| 05/25/2011 |  136.8 | 29.6 | 50.6 |
| 05/26/2011 |  136.3 | 28.8 | 51.0 |
| 05/27/2011 |  136.3 | 28.2 | 51.2 |
| 05/28/2011 |  136.3 | 28.9 | 50.9 |
| 05/29/2011 |  136.2 | 28.0 | 51.3 |
| 05/30/2011 |  135.9 | 28.8 | 50.9 |
| 05/31/2011 |  135.5 | 28.2 | 51.2 |
|------------+--------+------+------|
| 06/01/2011 |  135.1 | 28.2 | 51.2 |
| 06/02/2011 |  135.5 | 28.2 | 51.2 |
| 06/03/2011 |  134.8 | 28.9 | 50.9 |
| 06/04/2011 |  134.4 | 29.6 | 50.6 |
| 06/05/2011 |  134.2 | 27.9 | 51.3 |
| 06/06/2011 |  134.4 | 28.1 | 51.3 |
| 06/07/2011 |  133.2 | 29.2 | 50.8 |
| 06/08/2011 |  133.1 | 28.8 | 51.0 |
| 06/09/2011 |  133.0 | 28.6 | 51.0 |
| 06/10/2011 |  133.2 | 27.8 | 51.4 |
| 06/11/2011 |  132.2 | 27.9 | 51.4 |
| 06/12/2011 |  132.0 | 27.9 | 51.4 |
| 06/13/2011 |  132.1 | 28.9 | 51.0 |
| 06/14/2011 |  131.0 | 29.0 | 50.9 |
| 06/15/2011 |  130.2 | 27.6 | 51.5 |
|------------+--------+------+------|

I use the following Gnuplot script, Weight.plt that plots the weight, body fat percentage, absolute body fat, body water percentage and absolute body water.

# Weight plotter.

set terminal aqua title "Weight plot"
set xdata time
set timefmt '"%m/%d/%Y"'
set xlabel 'Date'

set multiplot

set size 1, 0.33

# Weight.
set origin 0, 0.66
set ylabel 'Weight in lb'
plot '$datafile' using 1:2 title 'Weight' with lines linecolor 2

set size 0.5, 0.33

# Body fat.
# Percentage.
set origin 0, 0.33
set ylabel 'Body fat %'
plot '$datafile' using 1:3 title 'Body fat %' with lines linecolor 1
# Absolute.
set origin 0.5, 0.33
set ylabel 'Body fat in lb'
plot '$datafile' using 1:($3 * $2 / 100) title 'Body fat' with lines linecolor 1

# Body water.
# Percentage.
set origin 0, 0
set ylabel 'Body water %'
plot '$datafile' using 1:4 title 'Body water %' with lines linecolor 3
# Absolute.
set origin 0.5, 0
set ylabel 'Body water in lb'
plot '$datafile' using 1:($4 * $2 / 100) title 'Body water' with lines linecolor 3

unset multiplot

Here is the screenshot of the generated plot. Click the thumbnail to get the actual size.

One of the reasons that I enjoyed this the most was due to the fact that I can totally correlate this comic to my behavior in naming things. I have an obsession of naming my laptops, servers, PCs, gadgets and more based on Greek mythological names. I am not sure how I developed this obsession. I think that it was mainly influenced by the games Zeus: Master of Olympus and Age of Mythology, the two games that I played a lot almost 8 years ago.

Here are some of the names of my stuff and the reason why I picked that name.

Item: Macbook Pro (Mac OS X)
Name: aphrodite – Aphrodite (Ἀφροδίτη (Áphroditē)) is the goddess of love and beauty.
Reason: This is my most favorite name. I use it for the personal machine that I spend time on.

Item: Primary development machine (Solaris 11)
Name: athena – Athena or Athene (Ἀθηνᾶ (Athēnâ)) is the goddess of wisdom, warfare, battle strategy, heroic endeavour, handicrafts and reason.
Reason: I use this name for my primary development machine at work and the primary trait that I care is wisdom.

Item: Messaging Server development server (Solaris 10)
Name: angelia – Angelia (Αγγελία) is the spirit of messages, tidings and proclamations.
Reason: It mainly deals with messages.

Item: Microsoft Windows VM
Name: erebos – Erebos (Ἔρεβος (Érebos)) is the god of darkness and shadow.
Reason: No comments.

Item: Apple iPhone
Name: Dionysus – Dionysus (Διόνυσος) is the god of wine, drunken orgies and wild vegetation.
Reason: It mainly represents the idea of socializing and parties.

Item: Apple iPad
Name: Ananke – Ananke (Ἀνάγκη (Anánkē)) is the goddess of inevitability, compulsion and necessity.
Reason: Well, iPad is a compulsion and necessity of the current generation, especially of magnified amplitude for people in the Valley.

Item: Buffalo wireless router
Name: aether – Aether (Αιθήρ) is the primeval god of the upper air.
Reason: For the power of sending/receiving tons of data over the air.

Item: Apple iPod Nano
Name: Terpsichore – Terpsichore (Τερψιχόρη) “delight of dancing” was one of the nine Muses, ruling over dance and the dramatic chorus.
Reason: Associated with fitness.

Item: Apple TV
Name: Hedone – Hedone (Ἡδονή), is the spirit of pleasure, enjoyment and delight.
Reason: Associated with entertainment/enjoyment.

Item: Canon EOS 50D camera
Name: Hyperion – Hyperion (Ὑπερίων (Hyperíōn)) is the titan of light. With Theia, he is the father of Helios (the sun), Selene (the moon) and Eos (the dawn).
Reason: What suits a camera better than the name of the titan of light!

Item: Honda Civic car
Name: Hermes – Hermes (Ἡρμῆς (Hērmē̂s)) is the god of travel, messengers, trade, thievery, cunning wiles, language, writing, diplomacy, athletics, and animal husbandry.
Reason: If the god of travel is with you, you are the master of roads.

Item: Citizen Skyhawk AT watch
Name: Chronos – Chronos (Χρόνος (Chrónos)) is the Keeper of Time. Not to be confused with the Titan Cronus, the father of Zeus.
Reason: What suits a clock that is so meticulous in keeping the accurate time using atomic time better than this name?

Item: Fuji CCR3 road bike
Name: Aura – Aura (Αὔρα (Aúra)) is the titan of the breeze and the fresh, cool air of early morning.
Reason: Mainly reflects the feeling that I get when I ride.

Item: Predator Sneaky Pete cue
Name: Oupis – Oupis (Ουπις), aiming aspect of archery.
Reason: That was the closest Greek mythological name that I was able to find related to pool.

Item: Atomic Smoke skis
Name: Chione – Chione (Χιόνη) is the goddess of snow and daughter of Boreas.
Reason: Isn’t that obvious?

You decide if I am crazy or not.

As you know, Emacs is highly extensible and it provides compilation-error-regexp-alist for accomplishing this. I have done this a couple of times earlier and I had to do it one more time lately for adding regular expression for Maven error messages. Construction of these regular expressions is not fun for everyone. However, regexp-builder makes it easier to construct the regular expression interactively.

Because the documentation around compilation-error-regexp-alist isn’t very intuitive for most, I have decided to make this screencast that describes how to approach this from scratch. Sorry about the typos! For best quality, watch it in HD.

In summary, here is the customization that has to be added to .emacs.

(add-to-list 'compilation-error-regexp-alist 'maven)
(add-to-list 'compilation-error-regexp-alist-alist
	     '(maven "\\[ERROR\\] \\(.+?\\):\\[\\([0-9]+\\),\\([0-9]+\\)\\].*"
		     1 2 3))

Here is what Emacs’s inbuilt documentation says about compilation-error-regular-expression-alist:

compilation-error-regexp-alist is a variable defined in `compile.el'.
Its value is 
(maven absoft ada aix ant bash borland caml comma edg-1 edg-2 epc ftnchek iar ibm irix java jikes-file jikes-line gnu gcc-include lcc makepp mips-1 mips-2 msft omake oracle perl php rxp sparc-pascal-file sparc-pascal-line sparc-pascal-example sun sun-ada watcom 4bsd gcov-file gcov-header gcov-nomark gcov-called-line gcov-never-called perl--Pod::Checker perl--Test perl--Test2 perl--Test::Harness weblint)
 
 
Documentation:
Alist that specifies how to match errors in compiler output.
On GNU and Unix, any string is a valid filename, so these
matchers must make some common sense assumptions, which catch
normal cases.  A shorter list will be lighter on resource usage.
 
Instead of an alist element, you can use a symbol, which is
looked up in `compilation-error-regexp-alist-alist'.  You can see
the predefined symbols and their effects in the file
`etc/compilation.txt' (linked below if you are customizing this).
 
Each elt has the form (REGEXP FILE [LINE COLUMN TYPE HYPERLINK
HIGHLIGHT...]).  If REGEXP matches, the FILE'th subexpression
gives the file name, and the LINE'th subexpression gives the line
number.  The COLUMN'th subexpression gives the column number on
that line.
 
If FILE, LINE or COLUMN are nil or that index didn't match, that
information is not present on the matched line.  In that case the
file name is assumed to be the same as the previous one in the
buffer, line number defaults to 1 and column defaults to
beginning of line's indentation.
 
FILE can also have the form (FILE FORMAT...), where the FORMATs
(e.g. "%s.c") will be applied in turn to the recognized file
name, until a file of that name is found.  Or FILE can also be a
function that returns (FILENAME) or (RELATIVE-FILENAME . DIRNAME).
In the former case, FILENAME may be relative or absolute.
 
LINE can also be of the form (LINE . END-LINE) meaning a range
of lines.  COLUMN can also be of the form (COLUMN . END-COLUMN)
meaning a range of columns starting on LINE and ending on
END-LINE, if that matched.
 
TYPE is 2 or nil for a real error or 1 for warning or 0 for info.
TYPE can also be of the form (WARNING . INFO).  In that case this
will be equivalent to 1 if the WARNING'th subexpression matched
or else equivalent to 0 if the INFO'th subexpression matched.
See `compilation-error-face', `compilation-warning-face',
`compilation-info-face' and `compilation-skip-threshold'.
 
What matched the HYPERLINK'th subexpression has `mouse-face' and
`compilation-message-face' applied.  If this is nil, the text
matched by the whole REGEXP becomes the hyperlink.
 
Additional HIGHLIGHTs as described under `font-lock-keywords' can
be added.
 
You can customize this variable.

For running the programs that are used in the class, I decided to use MIT/GNU Scheme. I am running GNU Emacs 23 on my Mac OS X. After some research, I figured out the best way of doing this is through xscheme.

First, download the MIT/GNU Scheme binary for Mac OS X and copy it to your Applications directory. Then configure Emacs to use the downloaded binary by adding the following lines to your .emacs.

(setq scheme-program-name
      "/Applications/mit-scheme.app/Contents/Resources/mit-scheme")
(require 'xscheme)

Now write your Scheme program.

; Compute the square root of a given number using successive
; approximation.
 
(define (sqrt value)
  (define (is-good-enough? guess value)
    (< (abs (- (* guess guess) value)) 0.0000001))
 
  (define (try guess value)
    (if (is-good-enough? guess value)
	guess
	(try (/ (+ guess (/ value guess)) 2) value)))
 
  (try 1 value))
 
(sqrt 4.0)

Invoke the Scheme process by 'M-x run-scheme'. Send the Scheme buffer to the Scheme process by 'M-o' and now you are able to run Scheme programs from Emacs.

Below is the screenshot of Scheme running under my Emacs session.

MIT Scheme running under GNU Emacs

When trying to build HBase from source, I noticed that the project was using Subversion for version control. I found it quite odd to see a modern project like HBase not using a distributed version control tool like Mercurial or Git. Soon, I realized that all Apache projects’ source code were maintained in Subversion. Then, I made a comment to my co-worker that, “Maybe Apache Foundation took over Subversion too!”, soon to realize that it was true. We learned that Subversion became an Apache Incubator project in 2009 and became an Apache top-level project in 2010.

I am really amazed by the number of projects that are now part of the Apache Software Foundation. Go Apache!

Here is the map of the ride.

Here is the map.

There were a lot of bicyclists on Foothill Expressway! Apart from some climbing at Arasterado, the ride was very smooth. Alpine is a downhill rideI really enjoyed this ride.

Last night, I created a rough map by hand. After returning from the ride, I spent some time on MapMyRide.com and created a detailed map for this loop.

Here is the map of the loop.

To look at the course fly-by video, continue reading the post.

Here is the course fly-by video.