lunatechian (lunatech-ian) - geek stuff

gitosis hint: does not appear to be a git repository

nospam@example.com (Raj Shekhar) — Wed, 01 Feb 2012 07:56:54 +0000

You have successfully installed gitosis, and you have been able to add users into gitosis. Now, on a remote computer, you try to checkout.

tearlayneed-lm:tmp rshekhar$ git clone ssh://stormcrow@home:221/gitosis-admin
Cloning into gitosis-admin...
fatal: '/gitosis-admin' does not appear to be a git repository
fatal: The remote end hung up unexpectedly

I am running the ssh server on port 221 and my username is stormcrow. If your reaction is WTF!, then I can sympathise with you. The correct clone command is

git clone ssh://stormcrow@home:221/~/gitosis-admin
Cloning into gitosis-admin...
remote: Counting objects: 24, done.

If you failed to notice, there is a ~ required.

rants by Kapil Sibal, with lolcats

nospam@example.com (Raj Shekhar) — Thu, 08 Dec 2011 08:13:32 +0000

Kapil Sibal, India's Telecoms minister has prompted an uproar after it was revealed he met with executives from Google and Facebook to pressure them into screening 'objectionable' content.

A side effect of Kapil Sibal trying to censor the internet is that he has been given a goldmine of comic quotes. And any quote looks adorable with a kitten. I converted his quotes to lolspeak and put them with pictures of cute kittens. The kittens should countereffect the increased blood pressure caused by his idocacy.

Without further ado, here are the cats with Kapil's quotes

U go and delete information on the Internet that might offend the sensibilities of people in India

We have to take care of the sensibilities of our people. Cultural ethos is very important to us.

There is some content on the Internet.. that any normal human being would be offended by

I have seen subject matter which was so offensive that it hurt religious sentiments of large sections of community

I decline to define what, exactly, is offensive content I am not offensive

Image credits

audit for incorrect engine

nospam@example.com (Raj Shekhar) — Thu, 22 Sep 2011 22:21:32 +0000

If you use innodb engine exclusively, and want to audit your databases for any tables that might have an incorrect engine, use the command below -

mysql -u root -p  information_schema -e \
"select TABLE_SCHEMA,TABLE_NAME, ENGINE from TABLES where\
 ENGINE != 'Innodb' \
 and TABLE_SCHEMA not in ('mysql','information_schema');"

a bag of tips

nospam@example.com (Raj Shekhar) — Wed, 22 Jun 2011 18:57:55 +0000

When you require a fake US address, use the one below. It should clear validity filters
123 Fake Street
Compton, CA - 90222

In linux, to find files modified today, use find . -mtime -1 \! -type d -exec ls -l {} \;

mysql startup debugging tip

nospam@example.com (Raj Shekhar) — Wed, 08 Jun 2011 07:19:03 +0000

If you are not able to start the mysql daemon repeatedly using your linux distribution init scripts and you are ready to pull out your hair in frustration, here is a tip that might help you in finding the problem.

Try running the mysqld_safe from the command line (without using the init scripts). Try running /usr/bin/mysqld_safe -v, which should spit out some debugging information.

If that fails, try calling the mysqld daemon directly from the command line, with the "-v" option . mysqld is usually present under /usr/sbin/mysqld. mysqld can be called with --print-defaults to get the command line options it would be run with.

/usr/sbin/mysqld would have been started with the following arguments: --user=mysql --pid-file=/var/run/mysqld/mysqld.pid ..... --max_binlog_size=100M

Try adding the -v option to these options to get more verbose details. When run from command line, mysqld will not detach from console and will print debugging info that might be useful in finding the cause of the error.

I suggest using 3 terminals to figure out what is going on

one terminal with tail -f /var/log/mysql/mysqld.err
one terminal with tail -f /var/log/messages
one terminal where I ran the mysqld_safe / mysqld command

The init scripts are usually good for day to day work. However, sometimes the init scripts can impede a innodb crash recovery process on a large database. Some init scripts have timeout built into them and they can kill mysql while the innodb is still trying to recover its tables.

happy star wars day!

nospam@example.com (Raj Shekhar) — Wed, 04 May 2011 18:58:27 +0000

MayThe4thBeWithYou

Celebrate the day by blowing up planets and kidnapping Princesses

Hair hacks toolkit

nospam@example.com (moblog) — Tue, 29 Mar 2011 05:30:57 +0000

Got my copy

nospam@example.com (Raj Shekhar) — Wed, 09 Mar 2011 03:21:09 +0000

Look what I got in my mail today . Bought it second hand at amazon. I am so pleased to see this is a hardcover edition. 6 bucks really well spent.

Caching is not a silver bullet

nospam@example.com (Raj Shekhar) — Wed, 16 Feb 2011 15:55:03 +0000

Let us take a this hypothetical situation. You have to serve a web page. You want the whole page to be sent back in 500 ms (milliseconds). If your user has a good network and he is not too far from your webserver, you can further assume that around 50 ms will be spent on the network. This means that you have 450 ms to collect all the data about this web request, do the fancy manipulations (sorting/filtering/updating files etc.) and serve it to the user. You need to make four external calls to get this data - 2 of them to an external web service and 2 of them to your own database.

Now assume that one of your external webservice calls take one second to send back the result 50% of the time and one of your database queries can take upto a second to give back the result 25% of the time. What will you do to make sure none of your users ever have to wait for more than 500 ms to get back the page? (500 ms excludes the time taken to download the images/css/do fancy javascript magic).

Humor in the bookstore

nospam@example.com (moblog) — Sat, 04 Dec 2010 01:00:34 +0000

"Atlas Shrugged" placed in the Humor section in the bookstore. The book on the left is "Undateable" and on the right is "11002 things to be miserable about". I salute the joker who did this - I liked the joke.

Yoda was supposed to be a monkey

nospam@example.com (Raj Shekhar) — Thu, 14 Oct 2010 14:56:47 +0000

When George Lucas and screenwriter Lawrence Kasdan decided to make the ancient Jedi at the heart of Luke's spiritual journey into a two-foot tall, pointy-eared alien, it wasn't clear how the character could actually be realized on screen using 1980 technology. At the time, animatronic technology wasn't thought to be advanced enough to pull off Yoda. .... they decided to try putting a trained monkey in a Yoda costume, including a full Yoda face mask. Rinzler showed a picture of the monkey on set, but he explained this idea was quickly abandoned when one of the people who worked on the primate scenes in 2001: A Space Odyssey pointed out "Look, the monkey's just going to pull off the mask over and over again. It's never going to work."

In the picture, a monkey is outfitted with a cane and a mask and measured. The simian was also briefly considered for walking shots of Minch-Yoda that would have been impossible to execute with a puppet.

Pic taken from Vanity Fair

make apt-get skip some packages in upgrade

nospam@example.com (Raj Shekhar) — Sat, 17 Jul 2010 19:34:26 +0000

When doing an apt-get upgrade on my Debian (Lenny) box yesterday I received this message

Since release 150, udev requires that support for the CONFIG_SYSFS_DEPRECATED feature is disabled in the running kernel. Please upgrade your kernel before or while upgrading udev.

This was holding back the upgrade of all the packages. Looked around a bit and it seems that the solution for this problem is to let apt know that we do not want to upgrade the udev package. The way to do this is echo "udev hold"|dpkg --set-selections and then run apt-get upgrade

today

nospam@example.com (Raj Shekhar) — Thu, 20 May 2010 05:52:39 +0000

I wore a pair of torn jeans to office today. I was trying to look fashionable, but I later saw that I was wearing a torn jacket as well. I hope I did not project an image of someone-who-does-not-get-paid-enough.

I watched the pilot of the X-Files tonight. Memorable quote

What I find fantastic is any notion that there are answers beyond the realm of science. The answers are there. You just have to know where to look.

Higher Order Perl

nospam@example.com (Raj Shekhar) — Sun, 03 Jan 2010 22:25:53 +0000

I am in love with the book Higher-Order Perl, especially the technique in the Chapter 2: Dispatch Tables.

word of the day: proscribe

nospam@example.com (Raj Shekhar) — Wed, 30 Dec 2009 16:40:40 +0000

Proscribe: to denounce or condemn (a thing) as dangerous or harmful; prohibit.

This word seems closely related to the word Prescribe, but I could not find any source which would mark proscribe as the antonym of proscribe.