@@ -22,3 +22,21 @@ You can increase the timeout or disable them completely with the following confi native: MemCache.new ['server1', 'server2'], { :timeout => 1.0 } # 1 second timeout + +== The new memcache-client is slower than 1.5.0!? + +Yes, in the simplest case, 1.6.x+ is slower than 1.5.0. If you just have a single memcached +server, the latest memcache-client will be significantly slower. This is because 1.5.0 does not +timeout network operations. For reliability purposes, memcache-client 1.6.x+ enables +timeouts by default. + +Unfortunately Ruby's network timeout options are not very performant. If you want timeouts, the +best you can do currently is install the SystemTimer gem, which will approximately halve the +overhead incurred by timeouts. If you need ultimate speed, you can disable timeouts or use Fauna's +memcached library which moves most of the client into native C. (Hint: if you are looking for a fun +tuning project and are good with C, the SystemTimer gem has a lot of room for improvement in +performance.) + +If you are using multiple memcached servers, 1.6.x+ will be much faster than 1.5.0 as 1.5.0 had an +extremely slow hashing function to map a key to a server. Overall, production environments with +multiple servers should see performance and reliability improvements in memcache-client 1.6.x+. \ No newline at end of file FAQ.rdoc f85d34a4fede48fd0f450184505938127476c8a0 Mike Perham mperham@gmail.com http://github.com/bmizerany/memcache-client/commit/d5ae15d362c379c3a6692e2d5b9beae545392cba d5ae15d362c379c3a6692e2d5b9beae545392cba 2009-04-13T20:28:03-07:00 2009-04-13T20:28:03-07:00 Add faq about 1.5.0 performance 6269a48b62bb707f034039c7aed4fd15677a2dc4 Mike Perham mperham@gmail.com