A small collection of tools to help monitor your Redis server.
Very tight client that connects to your server and stores the current date in a redistamp key every second. When used in a replicated environment, this allows you to easily check for replication lag.
These use the redis and hiredis gems, and install these via the bundler gem. By default, they install their gems into tools/gems; you can cd to tools and bundle exec ./tool.rb to run them.
Output is in JSON format, for easy integration with log monitoring solutions like Splunk.
Monitors the Redis slow query log and outputs any new entries it sees.
Traverses the Redis keyspace via SCAN and outputs guesstimates on memory usage. It assumes that you use a colon-separated key hierarchy, e.g. "foo:bar:baz"; if a key lacks any colons, it will try separating it by dashes and underscores instead.
If any tree node gets too leafy, it will prune it and just keep stats rather than filling up memory with all the sub-key names; for example, if you have 100,000 keys like a:* and only 50 keys like b:*, you'll see the usage of each individual b:* key, but the a:* keys will be rolled up into a single size for a. (This happens at any level except the root, so if you have too many unique root-level prefixes, you may use a lot of memory and get a lot of output.)
Since this puts a lot of load on Redis, it's meant to be run on a readonly slave rather than the master database, and will abort otherwise.