Changes since 5.4.2:
* Build system: Ability to make out-of-tree builds has been fixed.
* Build system, Disk and Users plugins: Detection and use of libstatgrab
>=0.90 has been added.
* Build system, Memory, CPU, TCPConns and Processes plugins: Numerous
fixes related to OpenBSD support have been added.
* Build system: Plugins now only export "module_register()".
* Build system: Various cleanups and improvements have been done.
* collectd: Numerous internal changes and improvements to the daemon and
the plugin API have been make.
* collectd: Numerous spelling mistakes have been corrected in comments
and documentation and several error messages have been improved.
* collectd: Rules/Targets can now be appended to existing Filter Chains.
* collectd: Failing Filter Chains destinations will now log the list of
available write targets.
* collectd: Support for process signaling and management by upstart and
systemd has been implemented for the Linux platform.
* collectd: The "CollectInternalStats" option has been added.
* collectd: The daemon source code and dependencies have moved to the
"src/daemon/" directory.
* collectd: The new "MaxReadInterval" option allows to cap the
exponential retry interval of plugins read errors.
* collectd: The "-P" command-line option now has precedence over the
"PIDFile" option.
* collection.cgi: Various data-source related adjustments have been made.
* libcollectdclient: Now propagates errors when signing / encrypting
network packets.
* Configuration: Support for unquoted IPv6 addresses has been added.
* Documentation: Various improvements have been done.
* Examples: the sample C plugin has been updated to the current plugin API.
* Licensing: The following components have been relicensed to the MIT
license: the Apple Sensors, Ascent, DBI, E-Mail, Entropy, GenericJMX,
gmond, LogFile, nginx, Notify Desktop, NTPd, NUT, olsrd, Perl, Ping,
PostgreSQL, Protocols, RouterOS, RRDCacheD, SNMP, StatsD, SysLog,
Table, Tail, UnixSock, vmem, VServer, Wireless, Write Riemann and XMMS
plugins, the core collectd daemon, the collectdmon, collectd-nagios
and collectd-tg utilities, all the Targets and Matches, liboconfig,
most of the "utils_*" files and the plugin API.
* Tests: A test suite has been added.
* Threshold: The hysteresis calculation has been made more reliable.
* Threshold: Various fixes and improvements have been made.
* AMQP plugin: The "ConnectionRetryDelay" option has been added,
allowing to delay reconnection.
* AMQP plugin: The "QueueDurable" and "QueueAutoDelete" options have
been added, giving control over queue creation and deletion.
* Apache, Ascent, BIND, cURL, cURL-JSON, cURL-XML, nginx and Write HTTP
plugins: Customizing the "User-Agent" field is now possible at
compile-time.
* Apache, Ascent, BIND, cURL, cURL-JSON, cURL-XML, nginx plugins: The
connection will be reset if it hasn't completed within the configured
"Interval". The new "Timeout" option gives control over this behavior.
* Apache, Ascent, cURL, cURL-JSON, cURL-XML, nginx, Write HTTP plugins:
Allow usernames and passwords to contain colons if built against
libcurl >= 7.19.1.
* Apache plugin: The "SSLCiphers" option gives control over the
encryption algorithms to use with TLS connections.
* Barometer plugin: This new plugin reads sensor data from various
Freescale and Bosch digital barometers.
* Battery plugin: Reporting values as percentages and reporting degraded
batteries has been added.
* Battery plugin: Support for reading values from sysfs on Linux has
been added.
* Battery plugin: The value for current is no longer supplied unless the
battery provides this information.
* BIND plugin: Bind's XML v3 API is now supported.
* Ceph plugin: This new plugin collects statistics from the Ceph
distributed storage system.
* ConnTrack plugin: Support for reporting values as percentages as well
as legacy conntrack files in "/proc" has been added.
* CPU plugin: The plugin is now able to report values as percentages and
aggregate values per-state and per-CPU.
* cURL-JSON plugin: Extracting values from complex JSON structures has
been enhanced.
* cURL-JSON plugin: Intervals can now be configured on a per-URL basis.
* cURL-JSON, cURL-XML, Write HTTP plugins: These plugins now also follow
HTTP redirects.
* cURL, cURL-JSON, cURL-XML plugins: HTTP Digest authentication has been
implemented.
* DBI, Oracle, PostgreSQL plugins: A "MetadataFrom" parameter has been
added which allows to set metadata from database columns.
* DBI plugin: Querying several databases in parallel is now possible.
* Disk plugin: On the Linux platform, disk names can now get looked up
in udev with the "UdevNameAttr" option.
* Disk plugin: This plugin now collects several additional I/O-related
metrics on the Linux platform.
* DRBD plugin: This new plugin reads Linux's Distributed Replicated
Block Device (DRBD) statistics.
* Exec, UnixSock plugins: The "PUTNOTIF" command now allows to set
metadata on notifications.
* fhcount plugin: This new plugin reports the number of used file handles.
* GenericJMX plugin: A Class Loader for "JMXConnectorFactory" has been
added, allowing the plugin to work with JBOSS > 7.
* IPC plugin: This new plugin collects information related to shared memory.
* Java plugin: Now uses the hostname defined in the configuration file.
* Load plugin: The plugin is now able to report values as percentages.
* Log Logstash plugin: This new plugin writes collectd logs and events
as Logstash JSON formatted events.
* LVM plugin: The plugin collects thin pool data volumes size, and no
longer reports virtual volumes.
* memcached plugin: "listen_disabled_num" are now also reported.
* Memory plugin: Slab memory reporting on the Linux platform has been added.
* Memory plugin: The plugin is now able to report values as percentages.
* Modbus plugin: Selecting between holding and input registers is now
possible.
* Modbus plugin: Support for accessing devices through an RS-485 serial
port has been added.
* Multimeter plugin: This plugin isn't built by default on the AIX
platform anymore.
* MySQL and PostgreSQL plugins: Passing "127.0.0.1" as a host will now
result in the global Hostname being used in metric names.
* MySQL plugin: InnoDB, Select and Sort statistics collection has been added.
* MySQL plugin: The "Alias" and "ConnectTimeout" options have been added.
* Netlink plugin: Support for 64bit netlink counters has been added.
* Network plugin: The "ReconnectInterval" configuration option has been added.
* NFS plugin: Support for NFSv4.0 has been implemented.
* OneWire plugin: Support for more temperature-providing sensor families
has been added.
* OneWire plugin: Support for full OWFS path and more device families
has been implemented.
* OpenLDAP plugin: This new plugin reads monitoring information from
OpenLDAP's "cn=Monitor" subtree.
* OpenVPN plugin: Support for OpenVPN 2.3.0 has been implemented.
* OpenVZ plugin: Various improvements have been made, making the plugin
report values like the other collectd plugins do.
* Perl plugin: A new "listval_filter" method has been added, various
internal cleanups and improvements have been made and a test suite has
been added.
* PostgreSQL plugin: The new "ExpireDelay" option allows skipping older
values pending write when the database slows down.
* PowerDNS plugin: The plugin was updated for stats from pdns 3.4.3.
* Processes plugin: A memory-usage related optimization for low-profile
systems has been added.
* Python plugin: Support for Python3 has been improved, "ModulePath" is
now prepended to "sys.path", and the "get_dataset()" function has been
added to the Python API.
* Redis and Write_Redis plugins: The support library has been switched
from credis to hiredis.
* Redis plugin: Custom commands can now be used to fetch values stored
in Redis.
* Redis plugin: Support for passwords up to 512 characters long has been added.
* Sensors plugin: Support for lm_sensors' power sensors has been added.
* SMART plugin: This new plugin collects SMART statistics from disk drives.
* SNMP plugin: A blacklist/whitelist feature can now be used to filter
which OIDs to collect.
* SNMP plugin: SNMPv3 authentication and encryption support has been
implemented.
* SNMP plugin: Two error messages have been disambiguated.
* Swap plugin: The plugin is now able to report values as percentages.
* Swap plugin: The plugin no longer fails on Linux systems where
"SwapCached" isn't exposed by the kernel.
* Tail plugin: "GaugeInc" and "GaugeAdd" options have been implemented.
* Tail plugin: Intervals can now be configured on a per-File basis.
* TCPConns plugin: The "AllPortsSummary" option, allowing to summarize
all connections, has been added.
* TCPConns plugin: Three metrics were renamed on the AIX platform, for
the sake of consistency.
* Turbostat plugin: This new plugin reads CPU frequency and C-state
residency on modern Intel turbo-capable processors.
* UnixSock plugin: The "GETTHRESHOLD" command has been re-added.
* Varnish plugin: Varnish 4 support has been added, as well as as
monitoring metrics only available in Varnish 4.
* virt plugin: Guests memory usage is now also collected.
* virt plugin: It is now possible to chose between using guests' name or
UUID as plugin_instance.
* virt plugin: The libvirt plugin has been renamed to virt.
* Write Graphite plugin: When the connection to graphite fails,
reconnection attempts are now limited to once per second.
* Write HTTP plugin: Multi-instance support of this plugin has been
improved. The "<URL "url">" block has been deprecated in favor of
"<Node "identifier">".
* Write HTTP plugin: Several TLS-related configuration options have been
added.
* Write HTTP plugin: The "LowSpeedLimit" and "Timeout" options allow to
reset slow/stalled network connections.
* Write HTTP plugin: The size of the payload posted to the HTTP server
can now be controlled with the "BufferSize" option.
* Write Kafka plugin: This new plugin sends data to Apache Kafka, a
distributed messaging queue.
ciomaire, Vincent Bernat, Marc Fournier. #670, #694, #794, #853, #014
* Write Log plugin: This new plugin dispatches collected values to the
configured log destination(s).
* Write Riemann plugin: Extra meta strings are now added as attributes
in notifications.
* Write Riemann plugin: Notification message are now sent to the Riemann
server via the description field.
* Write Riemann plugin: Support for custom attributes has been added.
* Write Riemann plugin: Support had been implemented for sending events
to Riemann in batches (when using TCP), and is enabled by default.
* Write Riemann plugin: The "EventServicePrefix" option has been added,
which adds a prefix to event service names.
* Write Riemann plugin: Threshold checks can now be passed down to the
Riemann server.
* Write Sensu plugin: This new plugin submits values to Sensu, a stream
processing and monitoring system.
* Write TSDB plugin: This new plugin sends data to OpenTSDB, a scalable
time series database.
* ZFS ARC plugin: Support for ZFS-on-Linux has been added.
* Zookeeper plugin: This new plugin reads data from the Apache Zookeeper
"MNTR" command.
collectd is a daemon which collects system performance statistics periodically
and provides mechanisms to store the values in a variety of ways, for example
in RRD-files.
