This is a great question, something I have pondered over quite a bit. I will summarize my lessons learned: You can easily use Lucene/Solr in lieu of MongoDB for pretty much all situations, but not vice versa. Grant Ingersoll’s post sums it up here. MongoDB etc. seem to serve a purpose where there is no … Read more
Memcached client library was just recently released as stable. It is being used by digg ( was developed for digg by Andrei Zmievski, now no longer with digg) and implements much more of the memcached protocol than the older memcache client. The most important features that memcached has are: Cas tokens. This made my life … Read more
Summary (TL;DR) Updated June 3rd, 2017 Redis is more powerful, more popular, and better supported than memcached. Memcached can only do a small fraction of the things Redis can do. Redis is better even where their features overlap. For anything new, use Redis. Memcached vs Redis: Direct Comparison Both tools are powerful, fast, in-memory data … Read more