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Diffstat (limited to 'python.d/go_expvar.chart.py')
| -rw-r--r-- | python.d/go_expvar.chart.py | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/python.d/go_expvar.chart.py b/python.d/go_expvar.chart.py new file mode 100644 index 00000000..e1a334cc --- /dev/null +++ b/python.d/go_expvar.chart.py @@ -0,0 +1,228 @@ +# -*- coding: utf-8 -*- +# Description: go_expvar netdata python.d module +# Author: Jan Kral (kralewitz) + +from __future__ import division +from base import UrlService +import json + +# default module values (can be overridden per job in `config`) +# update_every = 2 +priority = 60000 +retries = 60 + + +MEMSTATS_CHARTS = { + 'memstats_heap': { + 'options': ['heap', 'memory: size of heap memory structures', 'kB', 'memstats', 'expvar.memstats.heap', 'line'], + 'lines': [ + ['memstats_heap_alloc', 'alloc', 'absolute', 1, 1024], + ['memstats_heap_inuse', 'inuse', 'absolute', 1, 1024] + ]}, + 'memstats_stack': { + 'options': ['stack', 'memory: size of stack memory structures', 'kB', 'memstats', 'expvar.memstats.stack', 'line'], + 'lines': [ + ['memstats_stack_inuse', 'inuse', 'absolute', 1, 1024] + ]}, + 'memstats_mspan': { + 'options': ['mspan', 'memory: size of mspan memory structures', 'kB', 'memstats', 'expvar.memstats.mspan', 'line'], + 'lines': [ + ['memstats_mspan_inuse', 'inuse', 'absolute', 1, 1024] + ]}, + 'memstats_mcache': { + 'options': ['mcache', 'memory: size of mcache memory structures', 'kB', 'memstats', 'expvar.memstats.mcache', 'line'], + 'lines': [ + ['memstats_mcache_inuse', 'inuse', 'absolute', 1, 1024] + ]}, + 'memstats_live_objects': { + 'options': ['live_objects', 'memory: number of live objects', 'objects', 'memstats', 'expvar.memstats.live_objects', 'line'], + 'lines': [ + ['memstats_live_objects', 'live'] + ]}, + 'memstats_sys': { + 'options': ['sys', 'memory: size of reserved virtual address space', 'kB', 'memstats', 'expvar.memstats.sys', 'line'], + 'lines': [ + ['memstats_sys', 'sys', 'absolute', 1, 1024] + ]}, + 'memstats_gc_pauses': { + 'options': ['gc_pauses', 'memory: average duration of GC pauses', 'ns', 'memstats', 'expvar.memstats.gc_pauses', 'line'], + 'lines': [ + ['memstats_gc_pauses', 'avg'] + ]}, +} + +MEMSTATS_ORDER = ['memstats_heap', 'memstats_stack', 'memstats_mspan', 'memstats_mcache', 'memstats_sys', 'memstats_live_objects', 'memstats_gc_pauses'] + + +def flatten(d, top='', sep='.'): + items = [] + for key, val in d.items(): + nkey = top + sep + key if top else key + if isinstance(val, dict): + items.extend(flatten(val, nkey, sep=sep).items()) + else: + items.append((nkey, val)) + return dict(items) + + +class Service(UrlService): + def __init__(self, configuration=None, name=None): + UrlService.__init__(self, configuration=configuration, name=name) + + # if memstats collection is enabled, add the charts and their order + if self.configuration.get('collect_memstats'): + self.definitions = MEMSTATS_CHARTS + self.order = MEMSTATS_ORDER + else: + self.definitions = dict() + self.order = list() + + # if extra charts are defined, parse their config + extra_charts = self.configuration.get('extra_charts') + if extra_charts: + self._parse_extra_charts_config(extra_charts) + + def check(self): + """ + Check if the module can collect data: + 1) At least one JOB configuration has to be specified + 2) The JOB configuration needs to define the URL and either collect_memstats must be enabled or at least one + extra_chart must be defined. + + The configuration and URL check is provided by the UrlService class. + """ + + if not (self.configuration.get('extra_charts') or self.configuration.get('collect_memstats')): + self.error('Memstats collection is disabled and no extra_charts are defined, disabling module.') + return False + + return UrlService.check(self) + + def _parse_extra_charts_config(self, extra_charts_config): + + # a place to store the expvar keys and their types + self.expvars = dict() + + for chart in extra_charts_config: + + chart_dict = dict() + chart_id = chart.get('id') + chart_lines = chart.get('lines') + chart_opts = chart.get('options', dict()) + + if not all([chart_id, chart_lines]): + self.info('Chart {0} has no ID or no lines defined, skipping'.format(chart)) + continue + + chart_dict['options'] = [ + chart_opts.get('name', ''), + chart_opts.get('title', ''), + chart_opts.get('units', ''), + chart_opts.get('family', ''), + chart_opts.get('context', ''), + chart_opts.get('chart_type', 'line') + ] + chart_dict['lines'] = list() + + # add the lines to the chart + for line in chart_lines: + + ev_key = line.get('expvar_key') + ev_type = line.get('expvar_type') + line_id = line.get('id') + + if not all([ev_key, ev_type, line_id]): + self.info('Line missing expvar_key, expvar_type, or line_id, skipping: {0}'.format(line)) + continue + + if ev_type not in ['int', 'float']: + self.info('Unsupported expvar_type "{0}". Must be "int" or "float"'.format(ev_type)) + continue + + if ev_key in self.expvars: + self.info('Duplicate expvar key {0}: skipping line.'.format(ev_key)) + continue + + self.expvars[ev_key] = (ev_type, line_id) + + chart_dict['lines'].append( + [ + line.get('id', ''), + line.get('name', ''), + line.get('algorithm', ''), + line.get('multiplier', 1), + line.get('divisor', 100 if ev_type == 'float' else 1), + line.get('hidden', False) + ] + ) + + self.order.append(chart_id) + self.definitions[chart_id] = chart_dict + + def _get_data(self): + """ + Format data received from http request + :return: dict + """ + + raw_data = self._get_raw_data() + if not raw_data: + return None + + data = json.loads(raw_data) + + expvars = dict() + if self.configuration.get('collect_memstats'): + expvars.update(self._parse_memstats(data)) + + if self.configuration.get('extra_charts'): + # the memstats part of the data has been already parsed, so we remove it before flattening and checking + # the rest of the data, thus avoiding needless iterating over the multiply nested memstats dict. + del (data['memstats']) + flattened = flatten(data) + for k, v in flattened.items(): + ev = self.expvars.get(k) + if not ev: + # expvar is not defined in config, skip it + continue + try: + key_type, line_id = ev + if key_type == 'int': + expvars[line_id] = int(v) + elif key_type == 'float': + # if the value type is float, multiply it by 1000 and set line divisor to 1000 + expvars[line_id] = float(v) * 100 + except ValueError: + self.info('Failed to parse value for key {0} as {1}, ignoring key.'.format(k, key_type)) + del self.expvars[k] + + return expvars + + @staticmethod + def _parse_memstats(data): + + memstats = data['memstats'] + + # calculate the number of live objects in memory + live_objs = int(memstats['Mallocs']) - int(memstats['Frees']) + + # calculate GC pause times average + # the Go runtime keeps the last 256 GC pause durations in a circular buffer, + # so we need to filter out the 0 values before the buffer is filled + gc_pauses = memstats['PauseNs'] + try: + gc_pause_avg = sum(gc_pauses) / len([x for x in gc_pauses if x > 0]) + # no GC cycles have occured yet + except ZeroDivisionError: + gc_pause_avg = 0 + + return { + 'memstats_heap_alloc': memstats['HeapAlloc'], + 'memstats_heap_inuse': memstats['HeapInuse'], + 'memstats_stack_inuse': memstats['StackInuse'], + 'memstats_mspan_inuse': memstats['MSpanInuse'], + 'memstats_mcache_inuse': memstats['MCacheInuse'], + 'memstats_sys': memstats['Sys'], + 'memstats_live_objects': live_objs, + 'memstats_gc_pauses': gc_pause_avg, + } |