libwebsockets/lib/system/metrics/private-lib-system-metrics.h
Andy Green 3f4623bb36 lws_metrics
There are a few build options that are trying to keep and report
various statistics

 - DETAILED_LATENCY
 - SERVER_STATUS
 - WITH_STATS

remove all those and establish a generic rplacement, lws_metrics.

lws_metrics makes its stats available via an lws_system ops function
pointer that the user code can set.

Openmetrics export is supported, for, eg, prometheus scraping.
2021-03-08 21:47:28 +00:00

125 lines
4.2 KiB
C

/*
* lws System Metrics
*
* Copyright (C) 2021 Andy Green <andy@warmcat.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to
* deal in the Software without restriction, including without limitation the
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
* sell copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
* IN THE SOFTWARE.
*/
/*
* Const struct that describes a policy for processing raw metrics to turn them
* into events.
*
* Typically although we want to monitor every event, the data produced can be
* too large, and many events that are "normal" just need to be counted as such;
* outliers or change-to-continuous outliers may deserve closer recording as
* events in their own right.
*
* Mean computation must "decay" as it ages, we do this by halving the sum and
* count after .us_decay_unit us.
*
* We don't acknowledge outliers until there are at least .min_contributors
* in the current mean (which is subject to decaying)
*
* We decide something is an outlier event if it deviates from the mean by
* .pc_outlier_deviation %.
*/
/*
* The dynamic counterpart for each static metric policy, this is on heap
* one per const lws_metric_policy_t. It's listed in context->owner_mtr_dynpol
*/
typedef struct lws_metric_policy_dyn {
const lws_metric_policy_t *policy;
/**< the static part of the policy we belong to... can be NULL if no
* policy matches or the policy was invalidated */
lws_dll2_owner_t owner;
/**< list of metrics that are using this policy */
lws_dll2_t list;
/**< context owns us */
lws_sorted_usec_list_t sul;
/**< schedule periodic reports for metrics using this policy */
} lws_metric_policy_dyn_t;
/*
* A metrics private part, encapsulating the public part
*/
typedef struct lws_metric {
lws_dll2_t list;
/**< owned by either 1) ctx.lws_metric_policy_dyn_t.owner, or
* 2) ctx.owner_mtr_no_pol */
struct lws_context *ctx;
/* public part overallocated */
} lws_metric_t;
#if defined(LWS_WITH_SYS_METRICS)
#define lws_metrics_hist_bump_priv(_mt, _name) \
lws_metrics_hist_bump_(lws_metrics_priv_to_pub(_mt), _name)
#define lws_metrics_hist_bump_priv_wsi(_wsi, _hist, _name) \
lws_metrics_hist_bump_(lws_metrics_priv_to_pub(_wsi->a.context->_hist), _name)
#define lws_metrics_hist_bump_priv_ss(_ss, _hist, _name) \
lws_metrics_hist_bump_(lws_metrics_priv_to_pub(_ss->context->_hist), _name)
#define lws_metrics_priv_to_pub(_x) ((lws_metric_pub_t *)&(_x)[1])
#else
#define lws_metrics_hist_bump_priv(_mt, _name)
#define lws_metrics_hist_bump_priv_wsi(_wsi, _hist, _name)
#define lws_metrics_hist_bump_priv_ss(_ss, _hist, _name)
#define lws_metrics_priv_to_pub(_x) ((lws_metric_pub_t *)NULL)
#endif
#if defined(LWS_WITH_SECURE_STREAMS_PROXY_API)
/*
* sspc-specific version that also appends the tag value to the lifecycle tag
* used for logging the sspc identity
*/
int
lws_metrics_tag_sspc_add(struct lws_sspc_handle *ss, const char *name, const char *val);
#endif
int
lws_metrics_register_policy(struct lws_context *ctx,
const lws_metric_policy_t *head);
void
lws_metrics_destroy(struct lws_context *ctx);
void
lws_metric_event(lws_metric_t *mt, char go_nogo, u_mt_t val);
lws_metric_t *
lws_metric_create(struct lws_context *ctx, uint8_t flags, const char *name);
int
lws_metric_destroy(lws_metric_t **mt, int keep);
void
lws_metric_policy_dyn_destroy(lws_metric_policy_dyn_t *dm, int keep);
void
lws_metric_rebind_policies(struct lws_context *ctx);