• http://ui-patterns.com/collection/fat-footer
• http://www.seopher.com/articles/the_7_best_fat_footers_used_on_high_profile_sites
• http://bluhalo.wordpress.com/2008/01/17/our-top-ten-fat-footer-sites-revealed/
• http://www.onethingnew.com/category/weekend-web-developer/

Feed your footers away!!

• multi-Layered storage – ability to support layers of slower to faster disks and move data at block and/or file level between them atomically, keeping the most frequently read data on the fastest disks. If there is block level support for this it would be a boon for databases, where frequently accessed pages could be kept in faster SSDs and less frequently accessed pages would be stored on slower SATA drives
• Distributed – ability to have multiple clients participate and access a single virtual storage device
• Replicated – each file (or block) is replicated ‘n’ times using master-master sync/async replication
• No FSCK
• Self-healing
• Compression – native support for compression at file or block level (ideally the former)
  • Ability to access the file in its compressed form (useful where we can send out a compressed byte stream to the client and the uncompression is handled at the client)
• Snapshot capability
• Parity based RAID without write penalties (like Raid-Z)

ZFS supports many of the above features.

I never really got a handle on how one can judge humility of an individual, until it struck me recently. A technique that has actually effectively worked in the past, but I have never paid attention to it. Humble individuals are always respectful, and do not have an air about them. One of the ways I have been able to distinguish individuals who are not humble are those who feel specific interview questions are beneath them to answer. We have all seen this category. Often I will fire an extremely easy or fundamental or theoretical question in my interview to a candidate – and they will respond with a short answer – accompanied by negative body language or verbal cues or in some cases a direct rebuke that essentially states – “Are you kidding me? Why are you asking me such a question at my level. I am above this type of questioning.”

There are only two reasons (not mutually exclusive) for this type of a response – (1) Ignorance – the candidate does not know the answer to the question and instead of acknowledging it he prefers to go down the path of “this question is beneath me”, (2) Lack of Humility

At Directi -

• no question is ever beneath someone
• all of us know that we have a lot to learn
• none of us feel uncomfortable in acknowledging something we don’t know
• all of us are respectful

So if you want to judge the humility of an individual during an interview – ask a couple of really easy questions – and see how they respond

Do you feel you would fit into our work culture? Apply at http://careers.directi.com

• Start off by reading – Writing a Plugin – it lays down the framework of creating a plugin and defines what your plugin should be called, file names, structure and even a header for your plugin
• Next review – Plugin API – which describes the simple yet powerful Hooks, Filters and Actions mechanism provided by Wordpress to plugin developers
• Hooks are provided by WordPress to allow your plugin to ‘hook into’ the rest of WordPress; that is, to call functions in your plugin at specific times, and thereby set your plugin in motion.
• There are two kinds of hooks – Actions and Filters
• Actions are the hooks that the WordPress core launches at specific points during execution, or when specific events occur. Your plugin can specify that one or more of its PHP functions are executed at these points, using the Action API.
• Filters are the hooks that WordPress launches to modify text of various types before adding it to the database or sending it to the browser screen. Your plugin can specify that one or more of its PHP functions is executed to modify specific types of text at these times, using the Filter API.

I like the architecture – it allows any plugin developer to modify pretty much any functionality provided within Wordpress. Many application platforms can be modeled around this same event-based plugin architecture providing powerful extensibility to plugin developers.

I have gone through several iterations to remedy this situation – including carrying a projector (uncomfortable), buying a head-visor (resolution became an issue amongst other things), and researching foldable monitors, until I finally realized the only way was to lug my 22″ screen and keyboard/mouse assembly alongwith me.

I figured there are likely others like me – and there must be a product that makes this easy. Given my travel schedule for the next few weeks, I figured it is high time I took a look around, and sure enough, within a few minutes of Googling I came across this baby -

http://www.casesbypelican.com/monitorlcd.htm

They also have a 24″ version that carries just the LCD – http://www.casesbypelican.com/1690-30-lcdmonitor.htm

I am getting mine as we speak. Meanwhile, a few other links I came across are -

http://www.tenba.com/Categories/Air-Cases.aspx

http://www.casefoam.com/Flat%20Monitor%20Case.htm

Google

• April-June 2009 Revenue: $5.5 billion
• 97% of above revenues are from advertising
• April-June Revenue from Google Properties: $3.6 billion
• Total US revenue April-June Revenue from Google Properties: $2.6 billion
• Number of searches performed by Americans on Google Apr-June: 27.5 billion (approx) (source comscore)
• Revenue per search: 9.5 cents
• Revenue per 1000 searches: $95

Sources

• http://investor.google.com/documents/20090630_google_10Q.html#tx66132_2
• http://www.comscore.com/Press_Events/Press_Releases/2009/7/comScore_Releases_June_2009_U.S._Search_Engine_Rankings

Ask

• IAC total April-June Revenue: $340 million
• Revenue from Media and Ads (Ask.com, Citysearch, Dictionary.com etc): $168 million
• 84% of this is from US: $141
• 72% of this is proprietary properties => $101 million
• Bulk of this can be assumed to come from Ask.com (lets say $90 million)
• Number of searches performed by Americans on Google Apr-June: 1.5 billion (approx) (source comscore)
• Revenue per search: 6 cents
• Revenue per 1000 searches: $60

Sources

• http://investor.google.com/documents/20090630_google_10Q.html#tx66132_2
• http://www.comscore.com/Press_Events/Press_Releases/2009/7/comScore_Releases_June_2009_U.S._Search_Engine_Rankings

Facebook

• Dec 2008: 80 billion pageviews
• Registered users: 222 million
• Page views per user: 360 pageviews per user per month (or 12 pageviews per day avg)
• June 2009: 340 million unique visitors (77 million from US)
• May 2009: 87 billion page views (20 billion from US)
• Expected to generate over $500 million in revenue in 2009
• Rough total pageviews in 2009 => 1000 billion
• Rough Revenue per 1000 pageviews: 50 cents
• Breakup of their $550 million revenue – 125 – brand ads, 150 – deal with Msft, 75 – virtual goods, 200 – self service ads

Sources

• http://www.techcrunch.com/2009/01/22/facebook-now-nearly-twice-the-size-of-myspace-worldwide/
• http://www.techcrunch.com/2009/05/18/myspace-is-in-real-trouble-if-these-page-view-declines-dont-reverse/
• http://www.techcrunch.com/2009/08/04/facebook-is-now-the-fourth-largest-site-in-the-world/
• http://news.cnet.com/8301-13577_3-9973826-36.html
• http://www.reuters.com/article/ousiv/idUSTRE56531X20090706
• http://www.businessinsider.com/breaking-down-facebooks-revenues-2009-7
• http://www.insidefacebook.com/2009/07/06/andreessen-facebook-revenues-to-pass-500-million-in-2009-wouldnt-sell-shares-yet/

Baidu

• April-June 2009 revenue: $160 million
• Revenue per advertising customer: $791
• July 2008 Searches: 7.4 billion
• July 2008 quarter extrapolated: 22.2 billion searches
• Revenue in quarter of July 2008: $135.4 million
• Revenue per search: 0.6 cents
• Revenue per 1000 searches: $6

Sources

• http://www.comscore.com/Press_Events/Press_Releases/2008/09/Top_Asia-Pacific_Search_Engines
• http://ir.baidu.com/phoenix.zhtml?c=188488&p=irol-reportsAnnual

Linkedin

• Projected revenues in 2008: $100 million
• Revenue from Advertising: 25%
• Funding so far: $103 million
• Unique users as of 2009: 45 million
• March 2008 monthly visitors: 11 million
• March 2008 monthly pageviews: 115 million
• March 2008 avg minutes per visitor: 7.8 min

Sources

• http://www.marketingshift.com/2009/3/linkedins-financial-advantage-over-facebook.cfm
• http://www.techcrunch.com/2008/05/05/allen-co-pitching-linkedin-at-1-billion/
• http://www.readwriteweb.com/archives/online_business_networking_linkedin_xing.php

Ebay, Skype and Paypal

• April-June 2009 Revenue: $2 billion
• Marketplaces revenue (ebay.com, shopping.com etc): $1 billion (transaction) + $200 million (advertising)
• Marketplace Gross volume: $13.4 billion (ebay made around 10% of this in its revenues which is impressive)
• Payments revenue (paypal.com, bill-me-later): $630 million (transaction) + $39 million (advertising)
• International component of Payments revenue: $286.2 million (45%)
• Payments Total volume: $16.7 billion (ebay made around 3.9% here – which is surprising considering their paypal rates are much lower)
• Communications revenue (skype): $155 million (transaction) + $14 million (advertising)
• International component of Communications revenue: $128.5 million (83%)
• Skype registered users – 480 million
• Skypeout minutes – 2.9 billion
• Per user revenue – 32 cents per registered user per quarter
• Per user minutes – 6 minutes per user per quarter
• US revenue: $959 million
• International revenue: $1.1 billion
• Skype Q3 2007: 10 million concurrent online users at peak. 4 million at trough.

Sources

• http://ikeelliott.typepad.com/telecosm/2008/03/what-are-skypes.html
• http://investor.ebay.com/sec.cfm
• http://smallbiztrends.com/2009/04/skype-free-business-model-drives-revenue.html
• http://skypenumerology.blogspot.com/2007/10/skype-revenue.html

Apple

• Apr-June 2009 sales: $8.3 billion
• Geo distribution – America – 3.8, Europe – 2, others – remaining
• Product distribution – Mac – 3.3, ipod – 1.5, other music products – 1, iphone and related services – 1.6
• Units of product sold – Desktops – 0.8m, Portables – 1.7m, ipod – 10.2m, iphone – 5.2m

Sources

• http://www.apple.com/investor/

This week we visited 5 colleges. The process – an online test at CodeChef.com, a personal interview,a telephonic interview, and then a visit to our uber cool HQ at Mumbai for the final rounds. We hade several hundred students compete across multiple cities and institutions for the top spot in a fast-paced, fun hackfest at 5 different venues. So far 2 offers have been made. Our talent scouts – Ankush, Nishant, Anup and Anirban had fun, met a ton of interesting people and generally spread the word. Here are some pictures  and trivia -

Created with Admarket’s flickrSLiDR.

We (me and Div) went to Lake Tahoe for an evening, took off from San Carlos airport, had dinner at Lake Tahoe, won some money playing Poker and flew back. Cant wait till we get this baby shipped back to Mumbai – weekend trips to Goa whenever I want

Requirements

• Inifinite Scalability
• High Availability (0% downtime)
• Data Redundancy
• High Performance
• Storage Flexibility – ability to store any type of data
• Query Flexibility – ability to perform simple gets, range based gets, range based updates, and possibly complex joins

Features that a solution must have to deliver the above Requirements

• Replication – Each unit of data should be copied to multiple nodes so that if an underlying node crashes there is no data loss
• Partitioning – Data should be divided across multiple nodes based on specific keys so that the data layer is infinitely scalable
• Online node addition – Solution should support adding new nodes online, with automated data distribution upon new node addition
• Load Balancing – Queries should be load balanced between nodes
• Persistence – Should have a data persistence layer so that data is not volatile
• Caching – Should support flexible in-memory caching for increased retrieval speeds
• Tree based Indexing – To support range based queries ideally one may need tree type indexes for keys on which range queries maybe made

The holy grail of scalability is to be able to scale your data store. And as data stores go, RDBMSes seem to be the predominant choice (though that is changing – refer http://bit.ly/2lnRet). RDBMSes by their very nature, due to the features they provide (ACID compliance, Transaction safety etc) tend to be difficult to easily scale. This has resulted in the recent mushrooming of data storage options that are feature-poor but scalable out of the box (eg Voldemort, HyperTable etc)

I wanted to chronicle the list of features that a standard RDBMS provides, that we take for granted, so that I have a reference of the features that one may have to compromise on w.r.t application development in favor of easier scalability -

• Range based selects and updates – Being able to fire queries on a table specifying a range of values (eg where age >35). Typically RDBMSes use B+ Tree based indexes which support range based row selection. This in turn allows one to fire range based queries.
• Transactions – In an RDBMS one can perform multiple operations within a transaction and ensure that all of them or none of them go through. This ensures data integrity
• B+ tree indexes
• Foreign key relationships and referential integrity
• Joins and nested selects
• Aggregations (sum, avg etc)
• Advanced scripting using non-native languages (java etc)
• Stored procedures (allow encapsulation of business logic in the database layer)
• Triggers

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