Updated: June 11th, 2015

In the past few weeks I've been implementing advanced search at Plaxo, working quite closely with Solr enterprise search server. Today, I saw this relatively detailed comparison between Solr and its main competitor Sphinx (full credit goes to StackOverflow user mausch who had been using Solr for the past 2 years). For those still confused, Solr and Sphinx are similar to MySQL FULLTEXT search, or for those even more confused, think Google (yeah, this is a bit of a stretch, I know).


  • Both Solr and Sphinx satisfy all of your requirements. They're fast and designed to index and search large bodies of data efficiently.
  • Both have a long list of high-traffic sites using them (Solr, Sphinx

Updated: June 1st, 2008

Recently I ran into major problems using GNU diff. It would crash with "diff: memory exhausted" after only a few minutes trying to process the differences between a couple 4.5GB files. Even a beefy box with 9GB of RAM would run out of it in minutes.

There is a different solution, however, that is not dependent on file sizes. Enter rdiff – rsync's backbone. You can read about it here: http://en.wikipedia.org/wiki/Rsync (search for rdiff).

The upsides of rdiff are:

  • with the same 4.5GB files, rdiff only ate about 66MB of RAM and scaled very well. It never crashed to date.
  • it is also MUCH faster than diff.
  • rdiff itself combines both diff and patch capabilities, so you can create deltas