class TingYun::Agent::Collector::SqlSampler
This class contains the logic of recording slow SQL traces, which may represent multiple aggregated SQL queries.
A slow SQL trace consists of a collection of SQL instrumented SQL queries that all normalize to the same text. For example, the following two queries would be aggregated together into a single slow SQL trace:
SELECT * FROM table WHERE id=42 SELECT * FROM table WHERE id=1234
Each slow SQL trace keeps track of the number of times the same normalized query was seen, the min, max, and total time spent executing those queries, and an example backtrace from one of the aggregated queries.
Constants
- MAX_SAMPLES
Attributes
sql_traces[R]
Public Class Methods
new()
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# File lib/ting_yun/agent/collector/sql_sampler.rb, line 33 def initialize @sql_traces = {} @samples_lock = Mutex.new end
notice_sql(sql, metric_name, config, duration, state=nil, explainer=nil, binds=[], name="SQL")
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duration{:type => sec}
# File lib/ting_yun/agent/collector/sql_sampler.rb, line 45 def self.notice_sql(sql, metric_name, config, duration, state=nil, explainer=nil, binds=[], name="SQL") #THREAD_LOCAL_ACCESS sometimes start_time = Time.now.to_f state ||= TingYun::Agent::TransactionState.tl_get data = state.sql_sampler_transaction_data return unless data threshold = duration*1000 if threshold > TingYun::Agent.config[:'action_tracer.slow_sql_threshold'] && state.sql_recorded? backtrace = '' if threshold > TingYun::Agent.config[:'action_tracer.stack_trace_threshold'] backtrace = caller.reject! { |t| t.include?('tingyun_rpm') } backtrace = backtrace.first(20).join("\n") end statement = TingYun::Agent::Database::Statement.new(sql, config, explainer, binds, name) data.sql_data << ::TingYun::Agent::Collector::SlowSql.new(statement, metric_name, duration, start_time, backtrace) end end
on_start_transaction(state, uri)
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# File lib/ting_yun/agent/collector/sql_sampler.rb, line 38 def self.on_start_transaction(state, uri) return unless TingYun::Agent::Database.sql_sampler_enabled? state.init_sql_transaction(::TingYun::Agent::Collector::TransactionSqlData.new(uri)) end
Public Instance Methods
harvest!()
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# File lib/ting_yun/agent/collector/sql_sampler.rb, line 112 def harvest! return [] unless TingYun::Agent::Database.sql_sampler_enabled? slowest = [] @samples_lock.synchronize do slowest = @sql_traces.values @sql_traces = {} end slowest.each {|trace| trace.prepare_to_send } slowest end
has_room?()
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this should always be called under the @samples_lock
# File lib/ting_yun/agent/collector/sql_sampler.rb, line 107 def has_room? @sql_traces.size < MAX_SAMPLES end
merge!(sql_traces)
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# File lib/ting_yun/agent/collector/sql_sampler.rb, line 129 def merge!(sql_traces) @samples_lock.synchronize do sql_traces.each do |trace| existing_trace = @sql_traces[trace.sql] if existing_trace existing_trace.aggregate(trace.slow_sql, trace.path, trace.url) else @sql_traces[trace.sql] = trace end end end end
on_finishing_transaction(state, name)
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# File lib/ting_yun/agent/collector/sql_sampler.rb, line 62 def on_finishing_transaction(state, name) return unless TingYun::Agent::Database.sql_sampler_enabled? transaction_sql_data = state.sql_sampler_transaction_data return unless transaction_sql_data transaction_sql_data.set_transaction_name(name) save_slow_sql(transaction_sql_data) end
reset!()
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# File lib/ting_yun/agent/collector/sql_sampler.rb, line 123 def reset! @samples_lock.synchronize do @sql_traces = {} end end
save(transaction_sql_data)
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# File lib/ting_yun/agent/collector/sql_sampler.rb, line 83 def save (transaction_sql_data) action_metric_name = transaction_sql_data.metric_name uri = transaction_sql_data.uri transaction_sql_data.sql_data.each do |sql_item| normalized_sql = sql_item.normalize sql_trace = @sql_traces[normalized_sql] if sql_trace sql_trace.aggregate(sql_item, action_metric_name, uri) else if has_room? @sql_traces[normalized_sql] = ::TingYun::Agent::Collector::SqlTrace.new(normalized_sql, sql_item, action_metric_name, uri) else min, max = @sql_traces.minmax_by { |(_, trace)| trace.max_call_time } if max.last.max_call_time < sql_item.duration @sql_traces.delete(min.first) @sql_traces[normalized_sql] = ::TingYun::Agent::Collector::SqlTrace.new(normalized_sql, sql_item, action_metric_name, uri) end end end end end
save_slow_sql(data)
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# File lib/ting_yun/agent/collector/sql_sampler.rb, line 73 def save_slow_sql(data) size = data.sql_data.size if size > 0 @samples_lock.synchronize do ::TingYun::Agent.logger.debug "Examining #{size} slow transaction sql statement(s)" save data end end end