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Google Sorts 1 Petabyte In 6 Hours
krewemaynard writes "Google has announced that they were able to sort one petabyte of data in 6 hours and 2 minutes across 4,000 computers. According to the Google Blog, '... to put this amount in perspective, it is 12 times the amount of archived web data in the US Library of Congress as of May 2008. In comparison, consider that the aggregate size of data processed by all instances of MapReduce at Google was on average 20PB per day in January 2008.' The technology making this possible is MapReduce 'a programming model and an associated implementation for processing and generating large data sets.' We discussed it a few months ago. Google has also posted a video from their Technology RoundTable discussing MapReduce."
Consider a data set of two numbers, each .5 petabyte big. It should only take a few minutes to sort them and there's even a 50% chance the data is already sorted.
It's not enough to sort by blond, black, gay, scat, etc. Some categories are a combination that don't belong in a hierarchy.
That is where tagging comes in. Sorting can be done on-the-fly, with no one category intrinsically more important.
I suggest you read Slashdot
Exactly. It's unclear if their better time was a software engineering or algorithmic feat, though. Hadoop was able to finish sorting the 1 TB benchmark dataset in 209 s; TFA states Google pulled the same event off in 68 s. The Yahoo blog post you linked to says their compute nodes each sported 4 SATA HDDs. Note TFA mentions Google's 1 PB dataset sort used 48,000 HDDs split between 4,000 machines, or 12 HDDs to a machine. If Google used the same machines to perform their 1 TB sort, then they had 3 times as many HDDs on each compute node, and could probably pull data from storage 3 times as fast. 209 s / 68 s ~ 3.1 -- coincidence, or not? =)