One of the plugins was taking the wrong timestamp.

analytics/operators/persystsql/PerSystSqlOperator.cpp

@@ -162,14 +162,16 @@ void PerSystSqlOperator::compute(U_Ptr unit, qeJobData& jobData) {
 			}
 		}
 	}
-
+	uint64_t measurement_ts = 0;
 	if(_buffer.size() == 0){
 		LOG(error) << "PerSystSql Operator " << _name << ": no data in queryEngine found!";
 		return;
+	} else {
+		measurement_ts = _buffer[0].timestamp;
 	}
-
 	Aggregate_info_t agg_info;
-	compute_internal(unit, _buffer, agg_info);
+	agg_info.timestamp = (measurement_ts/1e9);
+	compute_internal(unit, _buffer, agg_info, measurement_ts); //it can't possibly be zero here
 
 	if( _backend == MARIADB ) {
 		if (!_persystdb->isInitialized()
@@ -192,7 +194,7 @@ void PerSystSqlOperator::compute(U_Ptr unit, qeJobData& jobData) {
 
 		_persystdb->updateJobsLastSuffix(jobData.jobId, jobData.userId, jobData.nodes.size(), agg_info.job_id_db, table_suffix);
 
-		agg_info.timestamp = (my_timestamp/1e9);
+
 		_persystdb->insertInAggregateTable(table_suffix, agg_info);
 	}
 }
@@ -205,12 +207,12 @@ void PerSystSqlOperator::convertToDoubles(std::vector<reading_t> &buffer, std::v
 }
 
 
-void PerSystSqlOperator::compute_internal(U_Ptr& unit, vector<reading_t>& buffer, Aggregate_info_t & agg_info) {
+void PerSystSqlOperator::compute_internal(U_Ptr& unit, vector<reading_t>& buffer, Aggregate_info_t & agg_info, uint64_t measurement_ts) {
 	_quantileSensors.clear();
 
 	reading_t reading;
 	AggregatorSensorBase::aggregationOps_t op;
-	reading.timestamp = getTimestamp() - _go_back_ns;
+	reading.timestamp = measurement_ts;
 
 	std::vector<double> douBuffer;
 	convertToDoubles(buffer, douBuffer);

analytics/operators/persystsql/PerSystSqlOperator.h

@@ -163,7 +163,7 @@ private:
 
 protected:
 	virtual void compute(U_Ptr unit) override;
-	void compute_internal(U_Ptr& unit, vector<reading_t>& buffer, Aggregate_info_t &agg_info);
+	void compute_internal(U_Ptr& unit, vector<reading_t>& buffer, Aggregate_info_t &agg_info, uint64_t measurement_ts);
 	double computeSeverityAverage(vector<double> & buffer);
 	void convertToDoubles(std::vector<reading_t> &buffer, std::vector<double> &douBuffer);
 	bool execOnStart() override;