diff options
Diffstat (limited to '')
-rw-r--r-- | web/api/queries/des/Makefile.am | 8 | ||||
-rw-r--r-- | web/api/queries/des/Makefile.in | 464 | ||||
-rw-r--r-- | web/api/queries/des/README.md | 66 | ||||
-rw-r--r-- | web/api/queries/des/des.c | 139 | ||||
-rw-r--r-- | web/api/queries/des/des.h | 17 |
5 files changed, 694 insertions, 0 deletions
diff --git a/web/api/queries/des/Makefile.am b/web/api/queries/des/Makefile.am new file mode 100644 index 000000000..19554bed8 --- /dev/null +++ b/web/api/queries/des/Makefile.am @@ -0,0 +1,8 @@ +# SPDX-License-Identifier: GPL-3.0-or-later + +AUTOMAKE_OPTIONS = subdir-objects +MAINTAINERCLEANFILES = $(srcdir)/Makefile.in + +dist_noinst_DATA = \ + README.md \ + $(NULL) diff --git a/web/api/queries/des/Makefile.in b/web/api/queries/des/Makefile.in new file mode 100644 index 000000000..d3f05587b --- /dev/null +++ b/web/api/queries/des/Makefile.in @@ -0,0 +1,464 @@ +# Makefile.in generated by automake 1.14.1 from Makefile.am. +# @configure_input@ + +# Copyright (C) 1994-2013 Free Software Foundation, Inc. + +# This Makefile.in is free software; the Free Software Foundation +# gives unlimited permission to copy and/or distribute it, +# with or without modifications, as long as this notice is preserved. + +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY, to the extent permitted by law; without +# even the implied warranty of MERCHANTABILITY or FITNESS FOR A +# PARTICULAR PURPOSE. + +@SET_MAKE@ + +# SPDX-License-Identifier: GPL-3.0-or-later + +VPATH = @srcdir@ +am__is_gnu_make = test -n '$(MAKEFILE_LIST)' && test -n '$(MAKELEVEL)' +am__make_running_with_option = \ + case $${target_option-} in \ + ?) ;; \ + *) echo "am__make_running_with_option: internal error: invalid" \ + "target option '$${target_option-}' specified" >&2; \ + exit 1;; \ + esac; \ + has_opt=no; \ + sane_makeflags=$$MAKEFLAGS; \ + if $(am__is_gnu_make); then \ + sane_makeflags=$$MFLAGS; \ + else \ + case $$MAKEFLAGS in \ + *\\[\ \ ]*) \ + bs=\\; \ + sane_makeflags=`printf '%s\n' "$$MAKEFLAGS" \ + | sed "s/$$bs$$bs[$$bs $$bs ]*//g"`;; \ + esac; \ + fi; \ + skip_next=no; \ + strip_trailopt () \ + { \ + flg=`printf '%s\n' "$$flg" | sed "s/$$1.*$$//"`; \ + }; \ + for flg in $$sane_makeflags; do \ + test $$skip_next = yes && { skip_next=no; continue; }; \ + case $$flg in \ + *=*|--*) continue;; \ + -*I) strip_trailopt 'I'; skip_next=yes;; \ + -*I?*) strip_trailopt 'I';; \ + -*O) strip_trailopt 'O'; skip_next=yes;; \ + -*O?*) strip_trailopt 'O';; \ + -*l) strip_trailopt 'l'; skip_next=yes;; \ + -*l?*) strip_trailopt 'l';; \ + -[dEDm]) skip_next=yes;; \ + -[JT]) skip_next=yes;; \ + esac; \ + case $$flg in \ + *$$target_option*) has_opt=yes; break;; \ + esac; \ + done; \ + test $$has_opt = yes +am__make_dryrun = (target_option=n; $(am__make_running_with_option)) +am__make_keepgoing = (target_option=k; $(am__make_running_with_option)) +pkgdatadir = $(datadir)/@PACKAGE@ +pkgincludedir = $(includedir)/@PACKAGE@ +pkglibdir = $(libdir)/@PACKAGE@ +pkglibexecdir = $(libexecdir)/@PACKAGE@ +am__cd = CDPATH="$${ZSH_VERSION+.}$(PATH_SEPARATOR)" && cd +install_sh_DATA = $(install_sh) -c -m 644 +install_sh_PROGRAM = $(install_sh) -c +install_sh_SCRIPT = $(install_sh) -c +INSTALL_HEADER = $(INSTALL_DATA) +transform = $(program_transform_name) +NORMAL_INSTALL = : +PRE_INSTALL = : +POST_INSTALL = : +NORMAL_UNINSTALL = : +PRE_UNINSTALL = : +POST_UNINSTALL = : +build_triplet = @build@ +host_triplet = @host@ +subdir = web/api/queries/des +DIST_COMMON = $(srcdir)/Makefile.in $(srcdir)/Makefile.am \ + $(dist_noinst_DATA) +ACLOCAL_M4 = $(top_srcdir)/aclocal.m4 +am__aclocal_m4_deps = $(top_srcdir)/build/m4/ax_c___atomic.m4 \ + $(top_srcdir)/build/m4/ax_c__generic.m4 \ + $(top_srcdir)/build/m4/ax_c_lto.m4 \ + $(top_srcdir)/build/m4/ax_c_mallinfo.m4 \ + $(top_srcdir)/build/m4/ax_c_mallopt.m4 \ + $(top_srcdir)/build/m4/ax_check_compile_flag.m4 \ + $(top_srcdir)/build/m4/ax_gcc_func_attribute.m4 \ + $(top_srcdir)/build/m4/ax_pthread.m4 \ + $(top_srcdir)/build/m4/jemalloc.m4 \ + $(top_srcdir)/build/m4/tcmalloc.m4 $(top_srcdir)/configure.ac +am__configure_deps = $(am__aclocal_m4_deps) $(CONFIGURE_DEPENDENCIES) \ + $(ACLOCAL_M4) +mkinstalldirs = $(install_sh) -d +CONFIG_HEADER = $(top_builddir)/config.h +CONFIG_CLEAN_FILES = +CONFIG_CLEAN_VPATH_FILES = +AM_V_P = $(am__v_P_@AM_V@) +am__v_P_ = $(am__v_P_@AM_DEFAULT_V@) +am__v_P_0 = false +am__v_P_1 = : +AM_V_GEN = $(am__v_GEN_@AM_V@) +am__v_GEN_ = $(am__v_GEN_@AM_DEFAULT_V@) +am__v_GEN_0 = @echo " GEN " $@; +am__v_GEN_1 = +AM_V_at = $(am__v_at_@AM_V@) +am__v_at_ = $(am__v_at_@AM_DEFAULT_V@) +am__v_at_0 = @ +am__v_at_1 = +SOURCES = +DIST_SOURCES = +am__can_run_installinfo = \ + case $$AM_UPDATE_INFO_DIR in \ + n|no|NO) false;; \ + *) (install-info --version) >/dev/null 2>&1;; \ + esac +DATA = $(dist_noinst_DATA) +am__tagged_files = $(HEADERS) $(SOURCES) $(TAGS_FILES) $(LISP) +DISTFILES = $(DIST_COMMON) $(DIST_SOURCES) $(TEXINFOS) $(EXTRA_DIST) +ACLOCAL = @ACLOCAL@ +AMTAR = @AMTAR@ +AM_DEFAULT_VERBOSITY = @AM_DEFAULT_VERBOSITY@ +AUTOCONF = @AUTOCONF@ +AUTOHEADER = @AUTOHEADER@ +AUTOMAKE = @AUTOMAKE@ +AWK = @AWK@ +CC = @CC@ +CCDEPMODE = @CCDEPMODE@ +CFLAGS = @CFLAGS@ +CPP = @CPP@ +CPPFLAGS = @CPPFLAGS@ +CYGPATH_W = @CYGPATH_W@ +DEFS = @DEFS@ +DEPDIR = @DEPDIR@ +ECHO_C = @ECHO_C@ +ECHO_N = @ECHO_N@ +ECHO_T = @ECHO_T@ +EGREP = @EGREP@ +EXEEXT = @EXEEXT@ +GREP = @GREP@ +INSTALL = @INSTALL@ +INSTALL_DATA = @INSTALL_DATA@ +INSTALL_PROGRAM = @INSTALL_PROGRAM@ +INSTALL_SCRIPT = @INSTALL_SCRIPT@ +INSTALL_STRIP_PROGRAM = @INSTALL_STRIP_PROGRAM@ +IPMIMONITORING_CFLAGS = @IPMIMONITORING_CFLAGS@ +IPMIMONITORING_LIBS = @IPMIMONITORING_LIBS@ +LDFLAGS = @LDFLAGS@ +LIBCAP_CFLAGS = @LIBCAP_CFLAGS@ +LIBCAP_LIBS = @LIBCAP_LIBS@ +LIBMNL_CFLAGS = @LIBMNL_CFLAGS@ +LIBMNL_LIBS = @LIBMNL_LIBS@ +LIBOBJS = @LIBOBJS@ +LIBS = @LIBS@ +LTLIBOBJS = @LTLIBOBJS@ +MAINT = @MAINT@ +MAKEINFO = @MAKEINFO@ +MATH_CFLAGS = @MATH_CFLAGS@ +MATH_LIBS = @MATH_LIBS@ +MKDIR_P = @MKDIR_P@ +NFACCT_CFLAGS = @NFACCT_CFLAGS@ +NFACCT_LIBS = @NFACCT_LIBS@ +OBJEXT = @OBJEXT@ +OPTIONAL_IPMIMONITORING_CFLAGS = @OPTIONAL_IPMIMONITORING_CFLAGS@ +OPTIONAL_IPMIMONITORING_LIBS = @OPTIONAL_IPMIMONITORING_LIBS@ +OPTIONAL_LIBCAP_CFLAGS = @OPTIONAL_LIBCAP_CFLAGS@ +OPTIONAL_LIBCAP_LIBS = @OPTIONAL_LIBCAP_LIBS@ +OPTIONAL_MATH_CLFAGS = @OPTIONAL_MATH_CLFAGS@ +OPTIONAL_MATH_LIBS = @OPTIONAL_MATH_LIBS@ +OPTIONAL_NFACCT_CLFAGS = @OPTIONAL_NFACCT_CLFAGS@ +OPTIONAL_NFACCT_LIBS = @OPTIONAL_NFACCT_LIBS@ +OPTIONAL_UUID_CLFAGS = @OPTIONAL_UUID_CLFAGS@ +OPTIONAL_UUID_LIBS = @OPTIONAL_UUID_LIBS@ +OPTIONAL_ZLIB_CLFAGS = @OPTIONAL_ZLIB_CLFAGS@ +OPTIONAL_ZLIB_LIBS = @OPTIONAL_ZLIB_LIBS@ +PACKAGE = @PACKAGE@ +PACKAGE_BUGREPORT = @PACKAGE_BUGREPORT@ +PACKAGE_NAME = @PACKAGE_NAME@ +PACKAGE_RPM_RELEASE = @PACKAGE_RPM_RELEASE@ +PACKAGE_RPM_VERSION = @PACKAGE_RPM_VERSION@ +PACKAGE_STRING = @PACKAGE_STRING@ +PACKAGE_TARNAME = @PACKAGE_TARNAME@ +PACKAGE_URL = @PACKAGE_URL@ +PACKAGE_VERSION = @PACKAGE_VERSION@ +PATH_SEPARATOR = @PATH_SEPARATOR@ +PKG_CONFIG = @PKG_CONFIG@ +PKG_CONFIG_LIBDIR = @PKG_CONFIG_LIBDIR@ +PKG_CONFIG_PATH = @PKG_CONFIG_PATH@ +PTHREAD_CC = @PTHREAD_CC@ +PTHREAD_CFLAGS = @PTHREAD_CFLAGS@ +PTHREAD_LIBS = @PTHREAD_LIBS@ +SET_MAKE = @SET_MAKE@ +SHELL = @SHELL@ +SSE_CANDIDATE = @SSE_CANDIDATE@ +STRIP = @STRIP@ +UUID_CFLAGS = @UUID_CFLAGS@ +UUID_LIBS = @UUID_LIBS@ +VERSION = @VERSION@ +ZLIB_CFLAGS = @ZLIB_CFLAGS@ +ZLIB_LIBS = @ZLIB_LIBS@ +abs_builddir = @abs_builddir@ +abs_srcdir = @abs_srcdir@ +abs_top_builddir = @abs_top_builddir@ +abs_top_srcdir = @abs_top_srcdir@ +ac_ct_CC = @ac_ct_CC@ +am__include = @am__include@ +am__leading_dot = @am__leading_dot@ +am__quote = @am__quote@ +am__tar = @am__tar@ +am__untar = @am__untar@ +ax_pthread_config = @ax_pthread_config@ +bindir = @bindir@ +build = @build@ +build_alias = @build_alias@ +build_cpu = @build_cpu@ +build_os = @build_os@ +build_target = @build_target@ +build_vendor = @build_vendor@ +builddir = @builddir@ +cachedir = @cachedir@ +chartsdir = @chartsdir@ +configdir = @configdir@ +datadir = @datadir@ +datarootdir = @datarootdir@ +docdir = @docdir@ +dvidir = @dvidir@ +exec_prefix = @exec_prefix@ +has_jemalloc = @has_jemalloc@ +has_tcmalloc = @has_tcmalloc@ +host = @host@ +host_alias = @host_alias@ +host_cpu = @host_cpu@ +host_os = @host_os@ +host_vendor = @host_vendor@ +htmldir = @htmldir@ +includedir = @includedir@ +infodir = @infodir@ +install_sh = @install_sh@ +libconfigdir = @libconfigdir@ +libdir = @libdir@ +libexecdir = @libexecdir@ +localedir = @localedir@ +localstatedir = @localstatedir@ +logdir = @logdir@ +mandir = @mandir@ +mkdir_p = @mkdir_p@ +nodedir = @nodedir@ +oldincludedir = @oldincludedir@ +pdfdir = @pdfdir@ +pluginsdir = @pluginsdir@ +prefix = @prefix@ +program_transform_name = @program_transform_name@ +psdir = @psdir@ +pythondir = @pythondir@ +registrydir = @registrydir@ +sbindir = @sbindir@ +sharedstatedir = @sharedstatedir@ +srcdir = @srcdir@ +sysconfdir = @sysconfdir@ +target_alias = @target_alias@ +top_build_prefix = @top_build_prefix@ +top_builddir = @top_builddir@ +top_srcdir = @top_srcdir@ +varlibdir = @varlibdir@ +webdir = @webdir@ +AUTOMAKE_OPTIONS = subdir-objects +MAINTAINERCLEANFILES = $(srcdir)/Makefile.in +dist_noinst_DATA = \ + README.md \ + $(NULL) + +all: all-am + +.SUFFIXES: +$(srcdir)/Makefile.in: @MAINTAINER_MODE_TRUE@ $(srcdir)/Makefile.am $(am__configure_deps) + @for dep in $?; do \ + case '$(am__configure_deps)' in \ + *$$dep*) \ + ( cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh ) \ + && { if test -f $@; then exit 0; else break; fi; }; \ + exit 1;; \ + esac; \ + done; \ + echo ' cd $(top_srcdir) && $(AUTOMAKE) --gnu web/api/queries/des/Makefile'; \ + $(am__cd) $(top_srcdir) && \ + $(AUTOMAKE) --gnu web/api/queries/des/Makefile +.PRECIOUS: Makefile +Makefile: $(srcdir)/Makefile.in $(top_builddir)/config.status + @case '$?' in \ + *config.status*) \ + cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh;; \ + *) \ + echo ' cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe)'; \ + cd $(top_builddir) && $(SHELL) ./config.status $(subdir)/$@ $(am__depfiles_maybe);; \ + esac; + +$(top_builddir)/config.status: $(top_srcdir)/configure $(CONFIG_STATUS_DEPENDENCIES) + cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh + +$(top_srcdir)/configure: @MAINTAINER_MODE_TRUE@ $(am__configure_deps) + cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh +$(ACLOCAL_M4): @MAINTAINER_MODE_TRUE@ $(am__aclocal_m4_deps) + cd $(top_builddir) && $(MAKE) $(AM_MAKEFLAGS) am--refresh +$(am__aclocal_m4_deps): +tags TAGS: + +ctags CTAGS: + +cscope cscopelist: + + +distdir: $(DISTFILES) + @srcdirstrip=`echo "$(srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \ + topsrcdirstrip=`echo "$(top_srcdir)" | sed 's/[].[^$$\\*]/\\\\&/g'`; \ + list='$(DISTFILES)'; \ + dist_files=`for file in $$list; do echo $$file; done | \ + sed -e "s|^$$srcdirstrip/||;t" \ + -e "s|^$$topsrcdirstrip/|$(top_builddir)/|;t"`; \ + case $$dist_files in \ + */*) $(MKDIR_P) `echo "$$dist_files" | \ + sed '/\//!d;s|^|$(distdir)/|;s,/[^/]*$$,,' | \ + sort -u` ;; \ + esac; \ + for file in $$dist_files; do \ + if test -f $$file || test -d $$file; then d=.; else d=$(srcdir); fi; \ + if test -d $$d/$$file; then \ + dir=`echo "/$$file" | sed -e 's,/[^/]*$$,,'`; \ + if test -d "$(distdir)/$$file"; then \ + find "$(distdir)/$$file" -type d ! -perm -700 -exec chmod u+rwx {} \;; \ + fi; \ + if test -d $(srcdir)/$$file && test $$d != $(srcdir); then \ + cp -fpR $(srcdir)/$$file "$(distdir)$$dir" || exit 1; \ + find "$(distdir)/$$file" -type d ! -perm -700 -exec chmod u+rwx {} \;; \ + fi; \ + cp -fpR $$d/$$file "$(distdir)$$dir" || exit 1; \ + else \ + test -f "$(distdir)/$$file" \ + || cp -p $$d/$$file "$(distdir)/$$file" \ + || exit 1; \ + fi; \ + done +check-am: all-am +check: check-am +all-am: Makefile $(DATA) +installdirs: +install: install-am +install-exec: install-exec-am +install-data: install-data-am +uninstall: uninstall-am + +install-am: all-am + @$(MAKE) $(AM_MAKEFLAGS) install-exec-am install-data-am + +installcheck: installcheck-am +install-strip: + if test -z '$(STRIP)'; then \ + $(MAKE) $(AM_MAKEFLAGS) INSTALL_PROGRAM="$(INSTALL_STRIP_PROGRAM)" \ + install_sh_PROGRAM="$(INSTALL_STRIP_PROGRAM)" INSTALL_STRIP_FLAG=-s \ + install; \ + else \ + $(MAKE) $(AM_MAKEFLAGS) INSTALL_PROGRAM="$(INSTALL_STRIP_PROGRAM)" \ + install_sh_PROGRAM="$(INSTALL_STRIP_PROGRAM)" INSTALL_STRIP_FLAG=-s \ + "INSTALL_PROGRAM_ENV=STRIPPROG='$(STRIP)'" install; \ + fi +mostlyclean-generic: + +clean-generic: + +distclean-generic: + -test -z "$(CONFIG_CLEAN_FILES)" || rm -f $(CONFIG_CLEAN_FILES) + -test . = "$(srcdir)" || test -z "$(CONFIG_CLEAN_VPATH_FILES)" || rm -f $(CONFIG_CLEAN_VPATH_FILES) + +maintainer-clean-generic: + @echo "This command is intended for maintainers to use" + @echo "it deletes files that may require special tools to rebuild." + -test -z "$(MAINTAINERCLEANFILES)" || rm -f $(MAINTAINERCLEANFILES) +clean: clean-am + +clean-am: clean-generic mostlyclean-am + +distclean: distclean-am + -rm -f Makefile +distclean-am: clean-am distclean-generic + +dvi: dvi-am + +dvi-am: + +html: html-am + +html-am: + +info: info-am + +info-am: + +install-data-am: + +install-dvi: install-dvi-am + +install-dvi-am: + +install-exec-am: + +install-html: install-html-am + +install-html-am: + +install-info: install-info-am + +install-info-am: + +install-man: + +install-pdf: install-pdf-am + +install-pdf-am: + +install-ps: install-ps-am + +install-ps-am: + +installcheck-am: + +maintainer-clean: maintainer-clean-am + -rm -f Makefile +maintainer-clean-am: distclean-am maintainer-clean-generic + +mostlyclean: mostlyclean-am + +mostlyclean-am: mostlyclean-generic + +pdf: pdf-am + +pdf-am: + +ps: ps-am + +ps-am: + +uninstall-am: + +.MAKE: install-am install-strip + +.PHONY: all all-am check check-am clean clean-generic cscopelist-am \ + ctags-am distclean distclean-generic distdir dvi dvi-am html \ + html-am info info-am install install-am install-data \ + install-data-am install-dvi install-dvi-am install-exec \ + install-exec-am install-html install-html-am install-info \ + install-info-am install-man install-pdf install-pdf-am \ + install-ps install-ps-am install-strip installcheck \ + installcheck-am installdirs maintainer-clean \ + maintainer-clean-generic mostlyclean mostlyclean-generic pdf \ + pdf-am ps ps-am tags-am uninstall uninstall-am + + +# Tell versions [3.59,3.63) of GNU make to not export all variables. +# Otherwise a system limit (for SysV at least) may be exceeded. +.NOEXPORT: diff --git a/web/api/queries/des/README.md b/web/api/queries/des/README.md new file mode 100644 index 000000000..fa546a338 --- /dev/null +++ b/web/api/queries/des/README.md @@ -0,0 +1,66 @@ +# double exponential smoothing + +Exponential smoothing is one of many window functions commonly applied to smooth data in signal +processing, acting as low-pass filters to remove high frequency noise. + +Simple exponential smoothing does not do well when there is a trend in the data. +In such situations, several methods were devised under the name "double exponential smoothing" +or "second-order exponential smoothing.", which is the recursive application of an exponential +filter twice, thus being termed "double exponential smoothing". + +In simple terms, this is like an average value, but more recent values are given more weight +and the trend of the values influences significantly the result. + +> **IMPORTANT** +> +> It is common for `des` to provide "average" values that far beyond the minimum or the maximum +> values found in the time-series. +> `des` estimates these values because of it takes into account the trend. + +This module implements the "Holt-Winters double exponential smoothing". + +Netdata automatically adjusts the weight (`alpha`) and the trend (`beta`) based on the number +of values processed, using the formula: + +``` +window = max(number of values, 15) +alpha = 2 / (window + 1) +beta = 2 / (window + 1) +``` + +You can change the fixed value `15` by setting in `netdata.conf`: + +``` +[web] + des max window = 15 +``` + +## how to use + +Use it in alarms like this: + +``` + alarm: my_alarm + on: my_chart +lookup: des -1m unaligned of my_dimension + warn: $this > 1000 +``` + +`des` does not change the units. For example, if the chart units is `requests/sec`, the result +will be again expressed in the same units. + +It can also be used in APIs and badges as `&group=des` in the URL. + +## Examples + +Examining last 1 minute `successful` web server responses: + +- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=min&after=-60&label=min) +- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=average&after=-60&label=average&value_color=yellow) +- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=ses&after=-60&label=single+exponential+smoothing&value_color=yellow) +- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=des&after=-60&label=double+exponential+smoothing&value_color=orange) +- ![](https://registry.my-netdata.io/api/v1/badge.svg?chart=web_log_nginx.response_statuses&options=unaligned&dimensions=success&group=max&after=-60&label=max) + +## References + +- [https://en.wikipedia.org/wiki/Exponential_smoothing](https://en.wikipedia.org/wiki/Exponential_smoothing). diff --git a/web/api/queries/des/des.c b/web/api/queries/des/des.c new file mode 100644 index 000000000..93d724723 --- /dev/null +++ b/web/api/queries/des/des.c @@ -0,0 +1,139 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#include <web/api/queries/rrdr.h> +#include "des.h" + + +// ---------------------------------------------------------------------------- +// single exponential smoothing + +struct grouping_des { + calculated_number alpha; + calculated_number alpha_other; + calculated_number beta; + calculated_number beta_other; + + calculated_number level; + calculated_number trend; + + size_t count; +}; + +static size_t max_window_size = 15; + +void grouping_init_des(void) { + long long ret = config_get_number(CONFIG_SECTION_WEB, "des max window", (long long)max_window_size); + if(ret <= 1) { + config_set_number(CONFIG_SECTION_WEB, "des max window", (long long)max_window_size); + } + else { + max_window_size = (size_t) ret; + } +} + +static inline calculated_number window(RRDR *r, struct grouping_des *g) { + (void)g; + + calculated_number points; + if(r->group == 1) { + // provide a running DES + points = r->internal.points_wanted; + } + else { + // provide a SES with flush points + points = r->group; + } + + // https://en.wikipedia.org/wiki/Moving_average#Exponential_moving_average + // A commonly used value for alpha is 2 / (N + 1) + return (points > max_window_size) ? max_window_size : points; +} + +static inline void set_alpha(RRDR *r, struct grouping_des *g) { + // https://en.wikipedia.org/wiki/Moving_average#Exponential_moving_average + // A commonly used value for alpha is 2 / (N + 1) + + g->alpha = 2.0 / (window(r, g) + 1.0); + g->alpha_other = 1.0 - g->alpha; + + //info("alpha for chart '%s' is " CALCULATED_NUMBER_FORMAT, r->st->name, g->alpha); +} + +static inline void set_beta(RRDR *r, struct grouping_des *g) { + // https://en.wikipedia.org/wiki/Moving_average#Exponential_moving_average + // A commonly used value for alpha is 2 / (N + 1) + + g->beta = 2.0 / (window(r, g) + 1.0); + g->beta_other = 1.0 - g->beta; + + //info("beta for chart '%s' is " CALCULATED_NUMBER_FORMAT, r->st->name, g->beta); +} + +void *grouping_create_des(RRDR *r) { + struct grouping_des *g = (struct grouping_des *)malloc(sizeof(struct grouping_des)); + set_alpha(r, g); + set_beta(r, g); + g->level = 0.0; + g->trend = 0.0; + g->count = 0; + return g; +} + +// resets when switches dimensions +// so, clear everything to restart +void grouping_reset_des(RRDR *r) { + struct grouping_des *g = (struct grouping_des *)r->internal.grouping_data; + g->level = 0.0; + g->trend = 0.0; + g->count = 0; + + // fprintf(stderr, "\nDES: "); + +} + +void grouping_free_des(RRDR *r) { + freez(r->internal.grouping_data); + r->internal.grouping_data = NULL; +} + +void grouping_add_des(RRDR *r, calculated_number value) { + struct grouping_des *g = (struct grouping_des *)r->internal.grouping_data; + + if(isnormal(value)) { + if(likely(g->count > 0)) { + // we have at least a number so far + + if(unlikely(g->count == 1)) { + // the second value we got + g->trend = value - g->trend; + g->level = value; + } + + // for the values, except the first + calculated_number last_level = g->level; + g->level = (g->alpha * value) + (g->alpha_other * (g->level + g->trend)); + g->trend = (g->beta * (g->level - last_level)) + (g->beta_other * g->trend); + } + else { + // the first value we got + g->level = g->trend = value; + } + + g->count++; + } + + //fprintf(stderr, "value: " CALCULATED_NUMBER_FORMAT ", level: " CALCULATED_NUMBER_FORMAT ", trend: " CALCULATED_NUMBER_FORMAT "\n", value, g->level, g->trend); +} + +calculated_number grouping_flush_des(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr) { + struct grouping_des *g = (struct grouping_des *)r->internal.grouping_data; + + if(unlikely(!g->count || !isnormal(g->level))) { + *rrdr_value_options_ptr |= RRDR_VALUE_EMPTY; + return 0.0; + } + + //fprintf(stderr, " RESULT for %zu values = " CALCULATED_NUMBER_FORMAT " \n", g->count, g->level); + + return g->level; +} diff --git a/web/api/queries/des/des.h b/web/api/queries/des/des.h new file mode 100644 index 000000000..360513e9c --- /dev/null +++ b/web/api/queries/des/des.h @@ -0,0 +1,17 @@ +// SPDX-License-Identifier: GPL-3.0-or-later + +#ifndef NETDATA_API_QUERIES_DES_H +#define NETDATA_API_QUERIES_DES_H + +#include "../query.h" +#include "../rrdr.h" + +extern void grouping_init_des(void); + +extern void *grouping_create_des(RRDR *r); +extern void grouping_reset_des(RRDR *r); +extern void grouping_free_des(RRDR *r); +extern void grouping_add_des(RRDR *r, calculated_number value); +extern calculated_number grouping_flush_des(RRDR *r, RRDR_VALUE_FLAGS *rrdr_value_options_ptr); + +#endif //NETDATA_API_QUERIES_DES_H |