CHANGES.markdown

Version 0.2.4

Minor bugfix release: fixes a few packaging issues and an obnoxious but nonfatal bug in the websocket server, introduced in 0.2.3.

Bugfixes

• Packages generate correct md5sums by default
• Tarball package logs to cwd, not /var/log/riemann.log.
• Aleph 0.3.1: fixes a bug which caused websockets to crash on the first conn

Internals

• Explicit gen-class for riemann.bin; aids in embedding Riemann in Java
• Early work towards testable configs

Version 0.2.3

Riemann continues to expand in scope and adaptability, especially adding support for integration with other monitoring systems. Metrics for riemann internals are now recorded and exposed as events through the standard streams. Packaging improvements and some minor performance/bugfixes round out the mix!

New features

• Comprehensive instrumentation for UDP, TCP, and Websocket servers, plus core; latencies, queue depths, and throughput
• Plugin system for loading external namespaces from the classpath.
• Standard deviation fold
• HipChat client
• Logstash client
• Support for passive Nagios checks
• HTTP server-sent-event transport

Improvements

• Librato adapter can take a sequence of events, e.g. from rollups. Much more efficient
• Improved error handling for Websockets HTTP server for 404 paths
• Custom attributes included in emails and SNS notifications
• config/include can now recursively load all files if given a directory
• Ratios are now formatted as doubles in email

Bugfixes

• Debian package now correctly respects $EXTRA_CLASSPATH
• No longer attempts to register SIGHUP handler on windows
• Index expiry no longer breaks on events with nil ttls
• Riemann.pool no longer sets :block-start true always
• Various docstring fixups
• Tarball now uses /usr/bin/env bash, not /bin/bash
• Fix an issue with start-stop-daemon on older Debian versions
• Load defaults from /etc/default on Debian

Internals

• Additional type hints; improves performance, especially for Graphite.
• mean-over-time is now deprecated
• Tests for graphite server
• Expanded test suite
• clojure 1.5.0 -> 1.5.1
• clj-librato 0.0.3
• riemann-clojure-client 0.2.9
• postal 1.11.1
• clj-time 0.6.0
• clj-http 0.7.7
• cheshire 5.2.0
• clj-wallhack 1.0.1
• clojure-complete 0.2.3
• netty 3.8.0-Final
• slf4j-log4j12 1.7.5
• slingshot 0.10.3
• clj-campfire 2.2.0
• less-awful-ssl 0.1.1
• tools.nrepl 0.2.3
• tools.logging 0.2.6
• org.clojure/java.classpath 0.2.1
• aleph 0.3.0
• incanter-core 1.5.4
• math.numeric-tower 0.0.2
• algo.generic 0.1.1

Version 0.2.2

New features

• HTTP server: PUT /events can take a series of JSON-encoded events
• Graphite server: can also speak Carbon over UDP
• riemann.sns: hooks in to Amazon's Simple Notification Service
• riemann.campfire: sends events to Campfire
• streams/apdex: the fraction of requests which are acceptable
• streams/clock-skew: detects clock skew between hosts
• streams/scale: multiplies metrics by a fixed factor
• streams/stable: passes on events with the same value for at least dt seconds
• Internal instrumentation: measures throughput and latency of streams
• Limited TLS support for tcp-server

Improvements

• Graphite pool: improved logging and saner concurrency defaults
• streams/periodically-until-expired (and dependent streams) now correctly handle their own expiry
• More type hints (reduces several performance bottlenecks in the index, pubsub, and graphite)!
• PID log message logs just the PID, not pid@host
• bin/riemann: easier to add custom jars and JVM options via /etc/defaults/

Bugfixes

• streams/where: tagged-any and tagged-all work correctly
• streams/where*: evaluates child streams only once
• streams/throttle: throttles expired events correctly
• count-string-bytes: fixed an error with multibyte chars
• Debian package: saner java deps, md5s for snapshot versions
• Reaper: reloads correctly when you change :keep-keys

Internals

• Removed need for AOT compilation
• No more gen-class for riemann.config
• Removed dependency on incanter-charts
• Services can declare that they conflict with other services.
• streams/part-time-simple: like part-time-fast, but with a saner API
• index/lookup: looks up an event by host and service
• riemann.email: Cleaned up deprecated formatting functions

Version 0.2.1

This is a small maintenance release to address a few issues with 0.2.0: most notably, an accidental transitive dependency on a snapshot release of Yammer Metrics which is no longer available.

New features

• streams/runs: detects runs of successive events.

Improvements

• Various documentation fixes.
• Riemann.pool uses a LinkedBlockingQueue--reports improved performance.

Bugfixes

• Fix dependencies on Aleph and Lamina which relied on a snapshot variant of Yammer Metrics.
• Debian package init script reports "already running" when appropriate.
• Debian package depends on Java.
• (streams core) is no longer lazy (fixes a possible threading issue).

Internals

• Some utility functions for emails got moved to riemann.common, to facilitate their re-use.

Version 0.2.0

Guess it's time we started a formal changelog. Version 0.2.0 is a fairly major improvement in Riemann's performance and capabilities. Many things have been solidified, expanded, or tuned, and there are a few completely new ideas as well.

There are a few minor API changes, mostly to internal structure--but a few streams are involved as well. Most functions will continue to work normally, but log a deprecation notice when used.

New features

• Arbitrary key-value (string) pairs on events
• Hot config reloading
• Integrated nrepl server
• streams/sdo: bind together multiple streams as one
• streams/split: like (cond), dispatch an event to the first matching stream
• streams/splitp: like split, but on the basis of a specific predicate
• config/delete-from-index: explicitly remove (similar) events from the index
• streams/top: streaming top-k
• streams/tag: add tags to events
• RPM packaging
• Init scripts, proper log dirs, and users for debian and RPM packages. Yeah, this means you can /etc/init.d/riemann reload, and Stuff Just Works (TM).
• folds/difference, product, and quotient.
• Folds come in sloppy and strict variants which should "Do What I Mean" in most contexts.
• Executor Services for asynchronous queued processing of events.
• streams/exception-stream: captures exceptions and converts them to events.

Improvements

• http://riemann.io site
• Lots more documentation and examples
• Config file syntax errors are detected early
• Cleaned up server logging
• Helpful messages (line numbers! filenames!) for configuration errors
• Silence closed channel exceptions
• Cores can preserve services like pubsub, the index, etc through reloads
• Massive speedups in TCP and UDP server throughput
• streams/rate works in real-time: no need for fill-in any more
• Graphite client is faster, more complete
• Config files can include other files by relative path
• streams/coalesce passes on expired events
• riemann.email/mailer can take custom :subject and :body functions
• riemann.config includes some common time/scheduling functions
• streams/where returns whether it matched an event, which means (where) is now re-usable as a predicate in lots of different contexts.
• streams/tagged-any and tagged-all return whether they matched
• streams/counter is resettable to a particular metric, and supports expiry
• Bring back "hyperspace core online"
• Update to netty 3.6.1
• Reduced the number of threadpools used by the servers
• Massive speedup in Netty performance by re-organizing execution handlers
• core/reaper takes a :keep-keys option to specify which fields on an event are preserved
• streams/smap ignores nil values for better use with folds
• Update to aleph 0.3.0-beta15
• Config files ship with emacs modelines, too

Bugfixes

• Fixed a bug in part-time-fast causing undercounting under high contention
• Catch exceptions while processing expired events
• Fix a bug escaping metric names for librato
• riemann.email/mailer can talk to SMTP relays again
• graphite-path-percentiles will convert decimals of three or more places to percentile strings
• streams/rollup is much more efficient; doesn't leak tasks
• streams/rollup aggregates and forwards expired events instead of stopping
• Fixed a threadpool leak from Netty
• streams/coalesce: fixed a bug involving lazy persistence of transients
• streams/ddt: fixed a few edge cases

Internals

• Cleaned up the test suite's logging
• Pluggable transports for netty servers
• Cores are immutable
• Service protocol: provides lifecycle management for internal components
• Tests for riemann.config
• riemann.periodic is gone; replaced by riemann.time
• Tried to clean up some duplicated functions between core, config, and streams
• riemann.common/deprecated
• Cleaned up riemann.streams, removing unused commented-out code
• Lots of anonymous functions have names now, to help with profiling
• Composing netty pipeline factories is much simpler
• Clojure 1.5

Known bugs

• Passing :host to websocket-server does nothing: it binds to * regardless.
• Folds/mean throws when it receives empty lists
• graphite-server has no tests
• Riemann will happily overload browsers via websockets
• streams/rate doesn't stop its internal poller correctly when self-expiring
• When Netty runs out of filehandles, it'll hang new connections