OpenTSDB 2.2.0 RC1

• Version 2.2.0 RC1 (2015-09-12)

Noteworthy Changes:

• Add the option to randomly assign UIDs to metrics to improve distribution across
  HBase region servers.
• Introduce salting of data to improve distribution of high cardinality regions
  across region servers.
• Introduce query stats for tracking various timings related to TSD queries.
• Add more stats endpoints including /threads, /jvm and /region_clients
• Allow for deleting UID mappings via CLI or the API
• Name the various threads for easier debugging, particularly for distinguishing
  between TSD and AsyncHBase threads.
• Allow for pre-fetching all of the meta information for the tables to improve
  performance.
• Update to the latest AsyncHBase with support for secure HBase clusters and RPC
  timeouts.
• Allow for overriding metric and tag widths via the config file. (Be careful!)
• URLs from the API are now relative instead of absolute, allowing for easier reverse
  proxy use.
• Allow for percent deviation in the Nagios check
• Let queries skip over unknown tag values that may not exist yet (via config)
• Add various query filters such as case (in)sensitive pipes, wildcards and pipes
  over tag values. Filters do not work over metrics at this time.
• Add support for writing data points using Appends in HBase as a way of writing
  compacted data without having to read and re-write at the top of each hour.
• Introduce an option to emit NaNs or Nulls in the JSON output when downsampling and
  a bucket is missing values.
• Introduce query time flags to show the original query along with some timing stats
  in the response.
• Introduce a storage exception handler plugin that will allow users to spool or
  requeue data points that fail writes to HBase due to various issues.
• Rework the HTTP pipeline to support plugins with RPC implementations.
• Allow for some style options in the Gnuplot graphs.
• Allow for timing out long running HTTP queries.
• Text importer will now log and continue bad rows instead of failing.
• New percentile and count aggregators.
• Add the /api/annotations endpoint to fetch multiple annotations in one call.
• Add a class to support improved bulk imports by batching requests in memory for a
  full hour before writing.

Bug Fixes:

• Modify the .rpm build to allow dashes in the name.
• Allow the Nagios check script to handle 0 values properly in checks.
• Fix FSCK where floating point values were not processed correctly (#430)
• Fix missing information from the /appi/uid/tsmeta calls (#498)
• Fix more issues with the FSCK around deleting columns that were in the list (#436)
• Avoid OOM issues over Telnet when the sending client isn't reading errors off it's
  socket fast enough by blocking writes.