X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=doc%2Fman%2Flttng-sessiond.8.txt;h=deda68c6471d63cfa378671b814c8c81e9b6e817;hp=df119e78beff0d79f3b70415536cb92bdce7066d;hb=6a0e3480d14f8691ea30855d1895e073bffc57d0;hpb=ee717bf064ade68f47c763d60c2d534fd9fd0b96 diff --git a/doc/man/lttng-sessiond.8.txt b/doc/man/lttng-sessiond.8.txt index df119e78b..deda68c64 100644 --- a/doc/man/lttng-sessiond.8.txt +++ b/doc/man/lttng-sessiond.8.txt @@ -1,5 +1,6 @@ lttng-sessiond(8) ================= +:revdate: 17 September 2018 NAME @@ -29,7 +30,7 @@ SYNOPSIS DESCRIPTION ----------- -The http://lttng.org/[_Linux Trace Toolkit: next generation_] is an open +The https://lttng.org/[_Linux Trace Toolkit: next generation_] is an open source software package used for correlated tracing of the Linux kernel, user applications, and user libraries. @@ -40,8 +41,8 @@ The _LTTng session daemon_ is a tracing registry which allows the user to interact with multiple tracers (kernel and user space) within the same container, a _tracing session_. Traces can be gathered from the Linux kernel and/or from instrumented applications (see -linklttng:lttng-ust(3)). You can aggregate and read the events of LTTng -traces using linklttng:babeltrace(1). +man:lttng-ust(3)). You can aggregate and read the events of LTTng +traces using man:babeltrace2(1). To trace the Linux kernel, the session daemon needs to be running as `root`. LTTng uses a _tracing group_ to allow specific users to interact @@ -61,19 +62,32 @@ NOTE: It is highly recommended to start the session daemon at boot time for stable and long-term tracing. -Loading tracing session configurations -~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -By default, the LTTng session daemon tries to load tracing session -configurations located in the user default directory -`$HOME/.lttng/sessions` and in the system one, `/etc/lttng/sessions`. +Automatic loading of tracing session configurations +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +When the session daemon starts, it automatically loads session +configuration files. + +The following directories are searched, non-recursively, in this order +for configuration files to load on launch: + +. `$LTTNG_HOME/.lttng/sessions/auto` (`$LTTNG_HOME` defaults to `$HOME`) +. +{system_sessions_auto_dir}+ + Note that both the directory containing the tracing session -configurations and the session daemon binary _must_ have the same UID +configurations _and_ the session daemon binary _must_ share the same UID for the configurations to be automatically loaded. -Specifying a path with the option:--load option overrides the default -directory _and_ the UID check. The session daemon simply checks if the -path is accessible and tries to load every tracing session configuration -in it. +The option:--load option overrides the default directories _and_ the UID +check. The session daemon simply checks if the path is accessible and +tries to load every tracing session configuration in it. When this +option is specified, the default directories are :not: searched for +configuration files. When the option is not specified, _both_ default +directories are searched for configuration files. + +If the option:--load option's argument is a directory, then all the +tracing session configurations found in all the files in this directory +are loaded. If the argument is a file, then all the tracing session +configurations found in this file are loaded. OPTIONS @@ -85,24 +99,26 @@ option:-b, option:--background:: Use the option:--daemonize option instead to close the file descriptors. +option:-f, option:--config='PATH':: + Load session daemon configuration from path 'PATH'. + option:-d, option:--daemonize:: Start as Unix daemon, and close file descriptors (console). Use the option:--background option instead to keep the file descriptors open. -option:-f, option:--config='PATH':: - Load session daemon configuration from path 'PATH'. - option:-g, option:--group='GROUP':: Use 'GROUP' as Unix tracing group (default: `tracing`). option:-l, option:--load='PATH':: - Automatically load tracing session configurations from path 'PATH'. + Automatically load tracing session configurations from 'PATH', + either a directory or a file, instead of loading them from the + default search directories. option:-S, option:--sig-parent:: Send `SIGUSR1` to parent process to notify readiness. + -NOTE: This is used by linklttng:lttng(1) to get notified when the +NOTE: This is used by man:lttng(1) to get notified when the session daemon is ready to accept commands. When building a third party tool on liblttng-ctl, this option can be very handy to synchronize the control tool and the session daemon. @@ -137,12 +153,13 @@ Paths and ports ~~~~~~~~~~~~~~~ option:--agent-tcp-port='PORT':: Listen on TCP port 'PORT' for agent application registrations - (default: 5345). + (default: a port within the range + [{default_agent_tcp_port_range_begin},{nbsp}{default_agent_tcp_port_range_end}]). -option:-a, option:--apps-sock='PATH':: +option:-a 'PATH', option:--apps-sock='PATH':: Set application Unix socket path to 'PATH'. -option:-c, option:--client-sock='PATH':: +option:-c 'PATH', option:--client-sock='PATH':: Set client Unix socket path to 'PATH'. option:--consumerd32-libdir='PATH':: @@ -209,11 +226,14 @@ ENVIRONMENT VARIABLES Note that command-line options override their equivalent environment variable. +`LTTNG_ABORT_ON_ERROR`:: + Set to 1 to abort the process after the first error is encountered. + `LTTNG_APP_SOCKET_TIMEOUT`:: Application socket's timeout (seconds) when sending/receiving commands. After this period of time, the application is unregistered by the session daemon. A value of 0 or -1 means an infinite timeout. - Default value: 5. + Default value: {default_app_socket_rw_timeout}. `LTTNG_CONSUMERD32_BIN`:: 32-bit consumer daemon binary path. @@ -261,6 +281,39 @@ The option:--kmod-probes option overrides this variable. Tracing session configuration XML schema definition (XSD) path. +FILES +----- +`$LTTNG_HOME/.lttng`:: + User LTTng runtime and configuration directory. + +`$LTTNG_HOME/lttng-traces`:: + Default output directory of LTTng traces. This can be overridden + with the nloption:--output option of the man:lttng-create(1) + command. + +`$LTTNG_HOME/.lttng/sessions/auto`:: + Directory from which user tracing configuration files are + automatically loaded when the session daemon starts (see + man:lttng-save(1) and man:lttng-load(1) for saving + and loading tracing sessions). + ++{system_sessions_auto_dir}+:: + Directory from which system-wide tracing configuration files are + automatically loaded when the session daemon starts (see + man:lttng-save(1) and man:lttng-load(1) for saving + and loading tracing sessions). + +`$LTTNG_HOME/.lttng/lttng.conf`:: + Default location of the session daemon configuration file (see the + option:--config option). + ++{system_lttng_conf}+:: + System-wide location of the session daemon configuration file (see + the option:--config option). + +NOTE: `$LTTNG_HOME` defaults to `$HOME` when not explicitly set. + + EXIT STATUS ----------- *0*:: @@ -290,8 +343,8 @@ include::common-footer.txt[] SEE ALSO -------- -linklttng:lttng(1), -linklttng:lttng-relayd(8), -linklttng:lttng-crash(1), -linklttng:lttng-ust(3), -linklttng:babeltrace(1) +man:lttng(1), +man:lttng-relayd(8), +man:lttng-crash(1), +man:lttng-ust(3), +man:babeltrace2(1)