1 collectd - System information collection daemon
2 =================================================
8 collectd is a small daemon which collects system information periodically
9 and provides mechanisms to store and monitor the values in a variety of
16 * collectd is able to collect the following data:
19 Apache server utilization: Number of bytes transferred, number of
20 requests handled and detailed scoreboard statistics
23 APC UPS Daemon: UPS charge, load, input/output/battery voltage, etc.
26 Sensors in Macs running Mac OS X / Darwin: Temperature, fan speed and
30 Various sensors in the Aquaero 5 water cooling board made by Aquacomputer.
33 Statistics about Ascent, a free server for the game `World of Warcraft'.
36 Reads absolute barometric pressure, air pressure reduced to sea level and
37 temperature. Supported sensors are MPL115A2 and MPL3115 from Freescale
38 and BMP085 from Bosch.
41 Batterycharge, -current and voltage of ACPI and PMU based laptop
45 Name server and resolver statistics from the `statistics-channel'
46 interface of BIND 9.5, 9,6 and later.
49 Statistics from the Ceph distributed storage system.
52 CPU accounting information for process groups under Linux.
55 Number of nf_conntrack entries.
58 Number of context switches done by the operating system.
61 CPU utilization: Time spent in the system, user, nice, idle, and related
65 CPU frequency (For laptops with speed step or a similar technology)
68 Parse statistics from websites using regular expressions.
71 Retrieves JSON data via cURL and parses it according to user
75 Retrieves XML data via cURL and parses it according to user
79 Executes SQL statements on various databases and interprets the returned
83 Mountpoint usage (Basically the values `df(1)' delivers)
86 Disk utilization: Sectors read/written, number of read/write actions,
87 average time an IO-operation took to complete.
90 DNS traffic: Query types, response codes, opcodes and traffic/octets
94 Collect individual drbd resource statistics.
97 Email statistics: Count, traffic, spam scores and checks.
98 See collectd-email(5).
101 Amount of entropy available to the system.
104 Network interface card statistics.
107 Values gathered by a custom program or script.
108 See collectd-exec(5).
111 File handles statistics.
114 Count the number of files in directories.
117 Linux file-system based caching framework statistics.
120 Receive multicast traffic from Ganglia instances.
123 Hard disk temperatures using hddtempd.
126 Interface traffic: Number of octets, packets and errors for each
130 IPC counters: semaphores used, number of allocated segments in shared
134 IPMI (Intelligent Platform Management Interface) sensors information.
137 Iptables' counters: Number of bytes that were matched by a certain
141 IPVS connection statistics (number of connections, octets and packets
142 for each service and destination).
143 See http://www.linuxvirtualserver.org/software/index.html.
146 IRQ counters: Frequency in which certain interrupts occur.
149 Integrates a `Java Virtual Machine' (JVM) to execute plugins in Java
150 bytecode. See “Configuring with libjvm” below.
153 System load average over the last 1, 5 and 15 minutes.
156 Detailed CPU statistics of the “Logical Partitions” virtualization
157 technique built into IBM's POWER processors.
160 Size of “Logical Volumes” (LV) and “Volume Groups” (VG) of Linux'
161 “Logical Volume Manager” (LVM).
164 Queries very detailed usage statistics from wireless LAN adapters and
165 interfaces that use the Atheros chipset and the MadWifi driver.
168 Motherboard sensors: temperature, fan speed and voltage information,
172 Linux software-RAID device information (number of active, failed, spare
176 Query and parse data from a memcache daemon (memcached).
179 Statistics of the memcached distributed caching system.
180 <http://www.danga.com/memcached/>
183 Memory utilization: Memory occupied by running processes, page cache,
184 buffer cache and free.
187 Collects CPU usage, memory usage, temperatures and power consumption from
188 Intel Many Integrated Core (MIC) CPUs.
191 Reads values from Modbus/TCP enabled devices. Supports reading values
192 from multiple "slaves" so gateway devices can be used.
195 Publishes and subscribes to MQTT topics.
198 Information provided by serial multimeters, such as the `Metex
202 MySQL server statistics: Commands issued, handlers triggered, thread
203 usage, query cache utilization and traffic/octets sent and received.
206 Plugin to query performance values from a NetApp storage system using the
207 “Manage ONTAP” SDK provided by NetApp.
210 Very detailed Linux network interface and routing statistics. You can get
211 (detailed) information on interfaces, qdiscs, classes, and, if you can
212 make use of it, filters.
215 Receive values that were collected by other hosts. Large setups will
216 want to collect the data on one dedicated machine, and this is the
217 plugin of choice for that.
220 NFS Procedures: Which NFS command were called how often. Only NFSv2 and
224 Collects statistics from `nginx' (speak: engine X), a HTTP and mail
228 NTP daemon statistics: Local clock drift, offset to peers, etc.
231 Information about Non-Uniform Memory Access (NUMA).
234 Network UPS tools: UPS current, voltage, power, charge, utilisation,
235 temperature, etc. See upsd(8).
238 Queries routing information from the “Optimized Link State Routing”
241 - onewire (EXPERIMENTAL!)
242 Read onewire sensors using the owcapu library of the owfs project.
243 Please read in collectd.conf(5) why this plugin is experimental.
246 Read monitoring information from OpenLDAP's cn=Monitor subtree.
249 RX and TX of each client in openvpn-status.log (status-version 2).
250 <http://openvpn.net/index.php/documentation/howto.html>
253 Query data from an Oracle database.
256 The perl plugin implements a Perl-interpreter into collectd. You can
257 write your own plugins in Perl and return arbitrary values using this
258 API. See collectd-perl(5).
261 Query statistics from BSD's packet filter "pf".
264 Receive and dispatch timing values from Pinba, a profiling extension for
268 Network latency: Time to reach the default gateway or another given
272 PostgreSQL database statistics: active server connections, transaction
273 numbers, block IO, table row manipulations.
276 PowerDNS name server statistics.
279 Process counts: Number of running, sleeping, zombie, ... processes.
282 Counts various aspects of network protocols such as IP, TCP, UDP, etc.
285 The python plugin implements a Python interpreter into collectd. This
286 makes it possible to write plugins in Python which are executed by
287 collectd without the need to start a heavy interpreter every interval.
288 See collectd-python(5) for details.
291 The redis plugin gathers information from a Redis server, including:
292 uptime, used memory, total connections etc.
295 Query interface and wireless registration statistics from RouterOS.
298 RRDtool caching daemon (RRDcacheD) statistics.
301 System sensors, accessed using lm_sensors: Voltages, temperatures and
305 RX and TX of serial interfaces. Linux only; needs root privileges.
308 Uses libsigrok as a backend, allowing any sigrok-supported device
309 to have its measurements fed to collectd. This includes multimeters,
310 sound level meters, thermometers, and much more.
313 Collect SMART statistics, notably load cycle count, temperature
317 Read values from SNMP (Simple Network Management Protocol) enabled
318 network devices such as switches, routers, thermometers, rack monitoring
319 servers, etc. See collectd-snmp(5).
322 Acts as a StatsD server, reading values sent over the network from StatsD
323 clients and calculating rates and other aggregates out of these values.
326 Pages swapped out onto hard disk or whatever is called `swap' by the OS..
329 Parse table-like structured files.
332 Follows (tails) log files, parses them by lines and submits matched
336 Follows (tails) files in CSV format, parses each line and submits
340 Bytes and operations read and written on tape devices. Solaris only.
343 Number of TCP connections to specific local and remote ports.
346 TeamSpeak2 server statistics.
349 Plugin to read values from `The Energy Detective' (TED).
352 Linux ACPI thermal zone information.
355 Reads the number of records and file size from a running Tokyo Tyrant
359 Reads CPU frequency and C-state residency on modern Intel
360 turbo-capable processors.
363 System uptime statistics.
366 Users currently logged in.
369 Various statistics from Varnish, an HTTP accelerator.
372 CPU, memory, disk and network I/O statistics from virtual machines.
375 Virtual memory statistics, e. g. the number of page-ins/-outs or the
376 number of pagefaults.
379 System resources used by Linux VServers.
380 See <http://linux-vserver.org/>.
383 Link quality of wireless cards. Linux only.
386 Bitrate and frequency of music played with XMMS.
389 Statistics for ZFS' “Adaptive Replacement Cache” (ARC).
392 Measures the percentage of cpu load per container (zone) under Solaris 10
396 Read data from Zookeeper's MNTR command.
398 * Output can be written or sent to various destinations by the following
402 Sends JSON-encoded data to an Advanced Message Queuing Protocol (AMQP)
403 server, such as RabbitMQ.
406 Write to comma separated values (CSV) files. This needs lots of
407 diskspace but is extremely portable and can be analysed with almost
408 every program that can analyse anything. Even Microsoft's Excel..
411 Send the data to a remote host to save the data somehow. This is useful
412 for large setups where the data should be saved by a dedicated machine.
415 Of course the values are propagated to plugins written in Perl, too, so
416 you can easily do weird stuff with the plugins we didn't dare think of
417 ;) See collectd-perl(5).
420 It's possible to implement write plugins in Python using the python
421 plugin. See collectd-python(5) for details.
424 Output to round-robin-database (RRD) files using the RRDtool caching
425 daemon (RRDcacheD) - see rrdcached(1). That daemon provides a general
426 implementation of the caching done by the `rrdtool' plugin.
429 Output to round-robin-database (RRD) files using librrd. See rrdtool(1).
430 This is likely the most popular destination for such values. Since
431 updates to RRD-files are somewhat expensive this plugin can cache
432 updates to the files and write a bunch of updates at once, which lessens
436 One can query the values from the unixsock plugin whenever they're
437 needed. Please read collectd-unixsock(5) for a description on how that's
441 Sends data to Carbon, the storage layer of Graphite using TCP or UDP. It
442 can be configured to avoid logging send errors (especially useful when
446 Sends the values collected by collectd to a web-server using HTTP POST
447 requests. The transmitted data is either in a form understood by the
448 Exec plugin or formatted in JSON.
451 Sends data to Apache Kafka, a distributed queue.
454 Writes data to the log
457 Sends data to MongoDB, a NoSQL database.
460 Sends the values to a Redis key-value database server.
463 Sends data to Riemann, a stream processing and monitoring system.
466 Sends data to Sensu, a stream processing and monitoring system, via the
467 Sensu client local TCP socket.
470 Sends data OpenTSDB, a scalable no master, no shared state time series
473 * Logging is, as everything in collectd, provided by plugins. The following
474 plugins keep us informed about what's going on:
477 Writes log messages to a file or STDOUT/STDERR.
480 Log messages are propagated to plugins written in Perl as well.
481 See collectd-perl(5).
484 It's possible to implement log plugins in Python using the python plugin.
485 See collectd-python(5) for details.
488 Logs to the standard UNIX logging mechanism, syslog.
491 Writes log messages formatted as logstash JSON events.
493 * Notifications can be handled by the following plugins:
496 Send a desktop notification to a notification daemon, as defined in
497 the Desktop Notification Specification. To actually display the
498 notifications, notification-daemon is required.
499 See http://www.galago-project.org/specs/notification/.
502 Send an E-mail with the notification message to the configured
506 Execute a program or script to handle the notification.
507 See collectd-exec(5).
510 Writes the notification message to a file or STDOUT/STDERR.
513 Send the notification to a remote host to handle it somehow.
516 Notifications are propagated to plugins written in Perl as well.
517 See collectd-perl(5).
520 It's possible to implement notification plugins in Python using the
521 python plugin. See collectd-python(5) for details.
523 * Value processing can be controlled using the "filter chain" infrastructure
524 and "matches" and "targets". The following plugins are available:
526 - match_empty_counter
527 Match counter values which are currently zero.
530 Match values using a hash function of the hostname.
533 Match values by their identifier based on regular expressions.
536 Match values with an invalid timestamp.
539 Select values by their data sources' values.
541 - target_notification
542 Create and dispatch a notification.
545 Replace parts of an identifier using regular expressions.
548 Scale (multiply) values by an arbitrary value.
551 Set (overwrite) entire parts of an identifier.
553 * Miscellaneous plugins:
556 Selects multiple value lists based on patterns or regular expressions
557 and creates new aggregated values lists from those.
560 Checks values against configured thresholds and creates notifications if
561 values are out of bounds. See collectd-threshold(5) for details.
564 Sets the hostname to a unique identifier. This is meant for setups
565 where each client may migrate to another physical host, possibly going
566 through one or more name changes in the process.
568 * Performance: Since collectd is running as a daemon it doesn't spend much
569 time starting up again and again. With the exception of the exec plugin no
570 processes are forked. Caching in output plugins, such as the rrdtool and
571 network plugins, makes sure your resources are used efficiently. Also,
572 since collectd is programmed multithreaded it benefits from hyper-threading
573 and multicore processors and makes sure that the daemon isn't idle if only
574 one plugin waits for an IO-operation to complete.
576 * Once set up, hardly any maintenance is necessary. Setup is kept as easy
577 as possible and the default values should be okay for most users.
583 * collectd's configuration file can be found at `sysconfdir'/collectd.conf.
584 Run `collectd -h' for a list of built-in defaults. See `collectd.conf(5)'
585 for a list of options and a syntax description.
587 * When the `csv' or `rrdtool' plugins are loaded they'll write the values to
588 files. The usual place for these files is beneath `/var/lib/collectd'.
590 * When using some of the plugins, collectd needs to run as user root, since
591 only root can do certain things, such as craft ICMP packages needed to ping
592 other hosts. collectd should NOT be installed setuid root since it can be
593 used to overwrite valuable files!
595 * Sample scripts to generate graphs reside in `contrib/' in the source
596 package or somewhere near `/usr/share/doc/collectd' in most distributions.
597 Please be aware that those script are meant as a starting point for your
598 own experiments.. Some of them require the `RRDs' Perl module.
599 (`librrds-perl' on Debian) If you have written a more sophisticated
600 solution please share it with us.
602 * The RRAs of the automatically created RRD files depend on the `step'
603 and `heartbeat' settings given. If change these settings you may need to
604 re-create the files, losing all data. Please be aware of that when changing
605 the values and read the rrdtool(1) manpage thoroughly.
608 collectd and chkrootkit
609 -----------------------
611 If you are using the `dns' plugin chkrootkit(1) will report collectd as a
612 packet sniffer ("<iface>: PACKET SNIFFER(/usr/sbin/collectd[<pid>])"). The
613 plugin captures all UDP packets on port 53 to analyze the DNS traffic. In
614 this case, collectd is a legitimate sniffer and the report should be
615 considered to be a false positive. However, you might want to check that
616 this really is collectd and not some other, illegitimate sniffer.
622 To compile collectd from source you will need:
624 * Usual suspects: C compiler, linker, preprocessor, make, ...
626 * A POSIX-threads (pthread) implementation.
627 Since gathering some statistics is slow (network connections, slow devices,
628 etc) collectd is parallelized. The POSIX threads interface is being
629 used and should be found in various implementations for hopefully all
632 * aerotools-ng (optional)
633 Used by the `aquaero' plugin. Currently, the `libaquaero5' library, which
634 is used by the `aerotools-ng' toolkit, is not compiled as a shared object
635 nor does it feature an installation routine. Therefore, you need to point
636 collectd's configure script at the source directory of the `aerotools-ng'
638 <https://github.com/lynix/aerotools-ng>
640 * CoreFoundation.framework and IOKit.framework (optional)
641 For compiling on Darwin in general and the `apple_sensors' plugin in
643 <http://developer.apple.com/corefoundation/>
645 * libatasmart (optional)
646 Used by the `smart' plugin.
647 <http://git.0pointer.de/?p=libatasmart.git>
650 The `turbostat' plugin can optionally build Linux Capabilities support,
651 which avoids full privileges requirement (aka. running as root) to read
653 <http://sites.google.com/site/fullycapable/>
655 * libclntsh (optional)
656 Used by the `oracle' plugin.
658 * libhiredis (optional)
659 Used by the redis plugin. Please note that you require a 0.10.0 version
660 or higher. <https://github.com/redis/hiredis>
663 If you want to use the `apache', `ascent', `bind', `curl', `curl_json',
664 `curl_xml', `nginx', or `write_http' plugin.
665 <http://curl.haxx.se/>
668 Used by the `dbi' plugin to connect to various databases.
669 <http://libdbi.sourceforge.net/>
671 * libesmtp (optional)
672 For the `notify_email' plugin.
673 <http://www.stafford.uklinux.net/libesmtp/>
675 * libganglia (optional)
676 Used by the `gmond' plugin to process data received from Ganglia.
677 <http://ganglia.info/>
679 * libgcrypt (optional)
680 Used by the `network' plugin for encryption and authentication.
681 <http://www.gnupg.org/>
684 If present, the `uuid' plugin will check for UUID from HAL.
685 <http://hal.freedesktop.org/>
687 * libi2c-dev (optional)
688 Used for the plugin `barometer', provides just the i2c-dev.h header file
689 for user space i2c development.
692 For querying iptables counters.
693 <http://netfilter.org/>
696 Library that encapsulates the `Java Virtual Machine' (JVM). This library is
697 used by the `java' plugin to execute Java bytecode. See “Configuring with
699 <http://openjdk.java.net/> (and others)
702 Used by the `openldap' plugin.
703 <http://www.openldap.org/>
706 Used by the `lvm' plugin.
707 <ftp://sources.redhat.com/pub/lvm2/>
709 * libmemcached (optional)
710 Used by the `memcachec' plugin to connect to a memcache daemon.
711 <http://tangent.org/552/libmemcached.html>
714 Used by the `netlink' plugin.
715 <http://www.netfilter.org/projects/libmnl/>
717 * libmodbus (optional)
718 Used by the `modbus' plugin to communicate with Modbus/TCP devices. The
719 `modbus' plugin works with version 2.0.3 of the library – due to frequent
720 API changes other versions may or may not compile cleanly.
721 <http://www.libmodbus.org/>
723 * libmysqlclient (optional)
724 Unsurprisingly used by the `mysql' plugin.
725 <http://dev.mysql.com/>
727 * libnetapp (optional)
728 Required for the `netapp' plugin.
729 This library is part of the “Manage ONTAP SDK” published by NetApp.
731 * libnetsnmp (optional)
732 For the `snmp' plugin.
733 <http://www.net-snmp.org/>
735 * libnotify (optional)
736 For the `notify_desktop' plugin.
737 <http://www.galago-project.org/>
739 * libopenipmi (optional)
740 Used by the `ipmi' plugin to prove IPMI devices.
741 <http://openipmi.sourceforge.net/>
743 * liboping (optional)
744 Used by the `ping' plugin to send and receive ICMP packets.
745 <http://octo.it/liboping/>
747 * libowcapi (optional)
748 Used by the `onewire' plugin to read values from onewire sensors (or the
750 <http://www.owfs.org/>
753 Used to capture packets by the `dns' plugin.
754 <http://www.tcpdump.org/>
756 * libperfstat (optional)
757 Used by various plugins to gather statistics under AIX.
760 Obviously used by the `perl' plugin. The library has to be compiled with
761 ithread support (introduced in Perl 5.6.0).
762 <http://www.perl.org/>
765 The PostgreSQL C client library used by the `postgresql' plugin.
766 <http://www.postgresql.org/>
768 * libprotobuf-c, protoc-c (optional)
769 Used by the `pinba' plugin to generate a parser for the network packets
770 sent by the Pinba PHP extension, and by the `write_riemann' plugin to
771 generate events to be sent to a Riemann server.
772 <http://code.google.com/p/protobuf-c/>
774 * libpython (optional)
775 Used by the `python' plugin. Currently, Python 2.3 and later and Python 3
777 <http://www.python.org/>
779 * librabbitmq (optional; also called “rabbitmq-c”)
780 Used by the `amqp' plugin for AMQP connections, for example to RabbitMQ.
781 <http://hg.rabbitmq.com/rabbitmq-c/>
783 * librdkafka (optional; also called “rdkafka”)
784 Used by the `write_kafka' plugin for producing messages and sending them
786 <https://github.com/edenhill/librdkafka>
788 * librouteros (optional)
789 Used by the `routeros' plugin to connect to a device running `RouterOS'.
790 <http://octo.it/librouteros/>
793 Used by the `rrdtool' and `rrdcached' plugins. The latter requires RRDtool
794 client support which was added after version 1.3 of RRDtool. Versions 1.0,
795 1.2 and 1.3 are known to work with the `rrdtool' plugin.
796 <http://oss.oetiker.ch/rrdtool/>
798 * librt, libsocket, libkstat, libdevinfo (optional)
799 Various standard Solaris libraries which provide system functions.
800 <http://developers.sun.com/solaris/>
802 * libsensors (optional)
803 To read from `lm_sensors', see the `sensors' plugin.
804 <http://www.lm-sensors.org/>
806 * libsigrok (optional)
807 Used by the `sigrok' plugin. In addition, libsigrok depends on glib,
808 libzip, and optionally (depending on which drivers are enabled) on
809 libusb, libftdi and libudev.
811 * libstatgrab (optional)
812 Used by various plugins to collect statistics on systems other than Linux
814 <http://www.i-scream.org/libstatgrab/>
816 * libtokyotyrant (optional)
817 Used by the `tokyotyrant' plugin.
818 <http://1978th.net/tokyotyrant/>
820 * libupsclient/nut (optional)
821 For the `nut' plugin which queries nut's `upsd'.
822 <http://networkupstools.org/>
825 Collect statistics from virtual machines.
826 <http://libvirt.org/>
829 Parse XML data. This is needed for the `ascent', `bind', `curl_xml' and
831 <http://xmlsoft.org/>
834 <http://www.xmms.org/>
837 Parse JSON data. This is needed for the `ceph', `curl_json' and
838 `log_logstash' plugins.
839 <http://github.com/lloyd/yajl>
841 * libvarnish (optional)
842 Fetches statistics from a Varnish instance. This is needed for the
844 <http://varnish-cache.org>
846 Configuring / Compiling / Installing
847 ------------------------------------
849 To configure, build and install collectd with the default settings, run
850 `./configure && make && make install'. For detailed, generic instructions
851 see INSTALL. For a complete list of configure options and their description,
852 run `./configure --help'.
854 By default, the configure script will check for all build dependencies and
855 disable all plugins whose requirements cannot be fulfilled (any other plugin
856 will be enabled). To enable a plugin, install missing dependencies (see
857 section `Prerequisites' above) and rerun `configure'. If you specify the
858 `--enable-<plugin>' configure option, the script will fail if the depen-
859 dencies for the specified plugin are not met. In that case you can force the
860 plugin to be built using the `--enable-<plugin>=force' configure option.
861 This will most likely fail though unless you're working in a very unusual
862 setup and you really know what you're doing. If you specify the
863 `--disable-<plugin>' configure option, the plugin will not be built. If you
864 specify the `--enable-all-plugins' or `--disable-all-plugins' configure
865 options, all plugins will be enabled or disabled respectively by default.
866 Explicitly enabling or disabling a plugin overwrites the default for the
867 specified plugin. These options are meant for package maintainers and should
868 not be used in everyday situations.
870 By default, collectd will be installed into `/opt/collectd'. You can adjust
871 this setting by specifying the `--prefix' configure option - see INSTALL for
872 details. If you pass DESTDIR=<path> to `make install', <path> will be
873 prefixed to all installation directories. This might be useful when creating
874 packages for collectd.
876 Configuring with libjvm
877 -----------------------
879 To determine the location of the required files of a Java installation is not
880 an easy task, because the locations vary with your kernel (Linux, SunOS, …)
881 and with your architecture (x86, SPARC, …) and there is no ‘java-config’
882 script we could use. Configuration of the JVM library is therefore a bit
885 The easiest way to use the `--with-java=$JAVA_HOME' option, where
886 `$JAVA_HOME' is usually something like:
887 /usr/lib/jvm/java-1.5.0-sun-1.5.0.14
889 The configure script will then use find(1) to look for the following files:
895 If found, appropriate CPP-flags and LD-flags are set and the following
896 library checks succeed.
898 If this doesn't work for you, you have the possibility to specify CPP-flags,
899 C-flags and LD-flags for the ‘Java’ plugin by hand, using the following three
900 (environment) variables:
906 For example (shortened for demonstration purposes):
908 ./configure JAVA_CPPFLAGS="-I$JAVA_HOME/include -I$JAVA_HOME/include/linux"
910 Adding "-ljvm" to the JAVA_LDFLAGS is done automatically, you don't have to
913 Generating the configure script
914 -------------------------------
916 Collectd ships with a `build.sh' script to generate the `configure'
917 script shipped with releases.
919 To generate the `configure` script, you'll need the following dependencies:
928 The `build.sh' script takes no arguments.
933 To compile correctly collectd needs to be able to initialize static
934 variables to NAN (Not A Number). Some C libraries, especially the GNU
935 libc, have a problem with that.
937 Luckily, with GCC it's possible to work around that problem: One can define
938 NAN as being (0.0 / 0.0) and `isnan' as `f != f'. However, to test this
939 ``implementation'' the configure script needs to compile and run a short
940 test program. Obviously running a test program when doing a cross-
941 compilation is, well, challenging.
943 If you run into this problem, you can use the `--with-nan-emulation'
944 configure option to force the use of this implementation. We can't promise
945 that the compiled binary actually behaves as it should, but since NANs
946 are likely never passed to the libm you have a good chance to be lucky.
948 Likewise, collectd needs to know the layout of doubles in memory, in order
949 to craft uniform network packets over different architectures. For this, it
950 needs to know how to convert doubles into the memory layout used by x86. The
951 configure script tries to figure this out by compiling and running a few
952 small test programs. This is of course not possible when cross-compiling.
953 You can use the `--with-fp-layout' option to tell the configure script which
954 conversion method to assume. Valid arguments are:
956 * `nothing' (12345678 -> 12345678)
957 * `endianflip' (12345678 -> 87654321)
958 * `intswap' (12345678 -> 56781234)
964 For questions, bug reports, development information and basically all other
965 concerns please send an email to collectd's mailing list at
966 <list at collectd.org>.
968 For live discussion and more personal contact visit us in IRC, we're in
969 channel #collectd on freenode.
975 Florian octo Forster <octo at collectd.org>,
976 Sebastian tokkee Harl <sh at tokkee.org>,
977 and many contributors (see `AUTHORS').
979 Please send bug reports and patches to the mailing list, see `Contact'