seastar::scollectd Namespace Reference

Detailed Description

Implementation of rudimentary collectd data gathering.

Usage is hopefully straight forward. Though, feel free to read https://collectd.org/wiki/index.php/Naming_schema for an explanation on the naming model.

Typically, you'll add values something like:

            scollectd::type_instance_id typ("<pluginname>", "<instance_name>", "<type_name>", "<instance_name>");
    scollectd::add_polled_metric(typ, [<metric var> | scollectd::make_typed(<data_type>, <metric_var>) [, ...]);

Where <pluginname> would be the overall 'module', e.g. "cpu" <instance_name> -> optional distinguisher between plugin instances. For cpu, the built-in scollectd::per_cpu_plugin_instance constant is a good choice, i.e. 0->N cpu. If there are no instances (e.g. only one), empty constant is appropriate (none) <type_name> is the 'type' of metric collected, for ex. "usage" (cpu/0/usage) <type_instance> is a distinguisher for metric parts of the type, e.g. "idle", "user", "kernel" -> cpu/0/usage/idle | cpu/0/usage/user | cpu/0/usage/kernel

Each type instance can bind an arbitrary number of values, ech representing some aspect in turn of the instance. The structure and interpretation is up to the producer/consumer

There is a single "scollectd" instance per cpu, and values should be bound locally to this cpu. Polling is done at a frequency set in the seastar config (def once per s), and all registered values will be sent via UDP packages to the destination host(s)

Note that the tuple { plugin, plugin_instance, type, type_instance } is considered a unique ID for a value registration, so using the same tuple twice will remove the previously registered values.

Values can be unregistered at any time, though they must be so on the same thread/cpu as they we're registered. The "registration" achor type provides RAII style value unregistration semantics.

Classes
struct	typed
class	type_instance_id
struct	options
struct	registration
class	registrations
struct	typed_value
class	plugin_instance_metrics
class	percpu_plugin_instance_metrics
struct	typed_value_impl
struct	data_type_for
struct	is_callable
struct	is_callable< T, std::enable_if_t<!std::is_void_v< std::invoke_result_t< T > >, void > >
struct	is_callable< T, std::enable_if_t< std::is_fundamental_v< T >, void > >
struct	data_type_for< T, std::enable_if_t< std::is_integral_v< T > &&std::is_unsigned_v< T >, void > >
struct	data_type_for< T, std::enable_if_t< std::is_floating_point_v< T >, void > >
struct	data_type_for< T, std::enable_if_t< is_callable< T >::value, void > >
struct	data_type_for< typed< T > >
class	value
class	value< typed< T > >
class	value_list
class	values_impl

Typedefs
using	data_type = seastar::metrics::impl::data_type
using	plugin_id = seastar::metrics::group_name_type
using	plugin_instance_id = seastar::metrics::instance_id_type
using	type_id = seastar::metrics::metric_type_def
using	type_instance = seastar::metrics::metric_name_type
using	description = seastar::metrics::description
typedef typed_value_impl< known_type::total_bytes >	total_bytes
typedef typed_value_impl< known_type::total_connections >	total_connections
typedef typed_value_impl< known_type::total_objects >	total_objects
typedef typed_value_impl< known_type::total_operations >	total_operations
typedef typed_value_impl< known_type::total_requests >	total_requests
typedef typed_value_impl< known_type::total_sessions >	total_sessions
typedef typed_value_impl< known_type::total_threads >	total_threads
typedef typed_value_impl< known_type::total_time_in_ms >	total_time_in_ms
typedef typed_value_impl< known_type::total_values >	total_values
typedef typed_value_impl< known_type::queue_length >	queue_length
typedef typed_value_impl< known_type::counter >	counter
typedef typed_value_impl< known_type::count >	count
typedef typed_value_impl< known_type::gauge >	gauge
typedef std::function< void()>	notify_function
using	collectd_value = seastar::metrics::impl::metric_value

Enumerations
enum class	known_type {   absolute , backends , bitrate , blocked_clients ,   bytes , cache_eviction , cache_operation , cache_ratio ,   cache_result , cache_size , capacity , changes_since_last_save ,   charge , clock_last_meas , clock_last_update , clock_mode ,   clock_reachability , clock_skew_ppm , clock_state , clock_stratum ,   compression , compression_ratio , connections , conntrack ,   contextswitch , count , counter , cpu ,   cpufreq , current , current_connections , current_sessions ,   delay , derive , df , df_complex ,   df_inodes , disk_io_time , disk_latency , disk_merged ,   disk_octets , disk_ops , disk_ops_complex , disk_time ,   dns_answer , dns_notify , dns_octets , dns_opcode ,   dns_qtype , dns_qtype_cached , dns_query , dns_question ,   dns_rcode , dns_reject , dns_request , dns_resolver ,   dns_response , dns_transfer , dns_update , dns_zops ,   drbd_resource , duration , email_check , email_count ,   email_size , entropy , evicted_keys , expired_keys ,   fanspeed , file_handles , file_size , files ,   flow , fork_rate , frequency , frequency_error ,   frequency_offset , fscache_stat , gauge , hash_collisions ,   http_request_methods , http_requests , http_response_codes , humidity ,   if_collisions , if_dropped , if_errors , if_multicast ,   if_octets , if_packets , if_rx_errors , if_rx_octets ,   if_tx_errors , if_tx_octets , invocations , io_octets ,   io_packets , ipt_bytes , ipt_packets , irq ,   latency , links , load , md_disks ,   memory , memory_lua , memory_throttle_count , multimeter ,   mutex_operations , objects , operations , packets ,   pending_operations , percent , percent_bytes , percent_inodes ,   ping , ping_droprate , ping_stddev , players ,   power , pressure , protocol_counter , pubsub ,   queue_length , records , requests , response_code ,   response_time , root_delay , root_dispersion , route_etx ,   route_metric , routes , segments , serial_octets ,   signal_noise , signal_power , signal_quality , snr ,   spl , swap , swap_io , tcp_connections ,   temperature , threads , time_dispersion , time_offset ,   time_offset_ntp , time_offset_rms , time_ref , timeleft ,   total_bytes , total_connections , total_objects , total_operations ,   total_requests , total_sessions , total_threads , total_time_in_ms ,   total_values , uptime , users , vcl ,   vcpu , virt_cpu_total , virt_vcpu , vmpage_action ,   vmpage_faults , vmpage_io , vmpage_number , volatile_changes ,   voltage , voltage_threshold , vs_memory , vs_processes ,   vs_threads }

Functions
template<typename T >
typed< T >	make_typed (data_type type, T &&t)
type_id	type_id_for (known_type)
void	configure (const options &)
void	remove_polled_metric (const type_instance_id &)
void	add_polled (const type_instance_id &, const shared_ptr< value_list > &, bool enabled=true)
template<typename... _Args>
static auto	make_type_instance (description d, _Args &&... args) -> values_impl< decltype(value< _Args >(std::forward< _Args >(args)))... >
template<typename ... _Args>
static type_instance_id	add_polled_metric (const plugin_id &plugin, const plugin_instance_id &plugin_instance, const type_id &type, const scollectd::type_instance &type_instance, _Args &&... args)
template<typename ... _Args>
static type_instance_id	add_polled_metric (const plugin_id &plugin, const plugin_instance_id &plugin_instance, const type_id &type, const scollectd::type_instance &type_instance, description d, _Args &&... args)
template<typename ... _Args>
static future	send_explicit_metric (const plugin_id &plugin, const plugin_instance_id &plugin_instance, const type_id &type, const scollectd::type_instance &type_instance, _Args &&... args)
template<typename ... _Args>
static notify_function	create_explicit_metric (const plugin_id &plugin, const plugin_instance_id &plugin_instance, const type_id &type, const scollectd::type_instance &type_instance, _Args &&... args)
seastar::metrics::impl::metric_id	to_metrics_id (const type_instance_id &id)
template<typename Arg >
static type_instance_id	add_polled_metric (const type_instance_id &id, description d, Arg &&arg, bool enabled=true)
template<typename Arg >
static type_instance_id	add_polled_metric (const type_instance_id &id, Arg &&arg)
template<typename Args >
static type_instance_id	add_disabled_polled_metric (const type_instance_id &id, description d, Args &&arg)
template<typename Args >
static type_instance_id	add_disabled_polled_metric (const type_instance_id &id, Args &&args)
template<typename ... Args>
static type_instance_id	add_disabled_polled_metric (const type_instance_id &id, Args &&... args)
template<typename ... _Args>
static future	send_explicit_metric (const type_instance_id &id, _Args &&... args)
template<typename ... _Args>
static notify_function	create_explicit_metric (const type_instance_id &id, _Args &&... args)
future	send_notification (const type_instance_id &id, const sstring &msg)
std::vector< collectd_value >	get_collectd_value (const scollectd::type_instance_id &id)
std::vector< scollectd::type_instance_id >	get_collectd_ids ()
sstring	get_collectd_description_str (const scollectd::type_instance_id &)
bool	is_enabled (const scollectd::type_instance_id &id)
void	enable (const scollectd::type_instance_id &id, bool enable)
metrics::impl::value_map	get_value_map ()

Variables
seastar::logger	logger
static constexpr unsigned	max_collectd_field_text_len = 63
const plugin_instance_id	per_cpu_plugin_instance

---

Class Documentation

seastar::scollectd::is_callable

struct seastar::scollectd::is_callable

Typedef Documentation

total_bytes

typedef typed_value_impl<known_type::total_bytes> seastar::scollectd::total_bytes

Deprecated:

metrics registration should be done using the metrics layer

Some typedefs for common used types. Feel free to add.

Function Documentation

add_disabled_polled_metric()

template<typename Args >

static type_instance_id seastar::scollectd::add_disabled_polled_metric ( const type_instance_id &  id, description  d, Args &&  arg  )

static

Deprecated:

metrics registration should be done using the metrics layer

add_polled_metric() [1/4]

template<typename ... _Args>

static type_instance_id seastar::scollectd::add_polled_metric ( const plugin_id &  plugin, const plugin_instance_id &  plugin_instance, const type_id &  type, const scollectd::type_instance &  type_instance, _Args &&...  args  )

static

Deprecated:

metrics registration should be done using the metrics layer

add_polled_metric() [2/4]

template<typename ... _Args>

static type_instance_id seastar::scollectd::add_polled_metric ( const plugin_id &  plugin, const plugin_instance_id &  plugin_instance, const type_id &  type, const scollectd::type_instance &  type_instance, description  d, _Args &&...  args  )

static

Deprecated:

metrics registration should be done using the metrics layer

add_polled_metric() [3/4]

template<typename Arg >

static type_instance_id seastar::scollectd::add_polled_metric ( const type_instance_id &  id, Arg &&  arg  )

static

Deprecated:

metrics registration should be done using the metrics layer

add_polled_metric() [4/4]

template<typename Arg >

static type_instance_id seastar::scollectd::add_polled_metric ( const type_instance_id &  id, description  d, Arg &&  arg, bool  enabled = true  )

static

Deprecated:

metrics registration should be done using the metrics layer

enable()

void seastar::scollectd::enable	(	const scollectd::type_instance_id &	id,
		bool	enable
	)

Enable or disable collectd metrics on local instance

Parameters

id	- the metric to enable or disable
enable	- should the collectd metrics be enable or disable