I have a function that queries multiple partition asynchronously and combine the result it works well when one thread is executing this function, but performance degrades for all threads when multiple threads parallelly execute this function, I am not able to understand why is this happening. Below is my function.
@Override
public List<ConversationDetail> getConversationDetailByCreateDateAndCmId(Timestamp startDateTimestamp, Timestamp endDateTimestamp, int cmId) {
LocalDate startDate = startDateTimestamp.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
LocalDate endDate = endDateTimestamp.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
List<ConversationDetail> results = new ArrayList<>();
List<ResultSetFuture> futures = new ArrayList<>();
try {
for (LocalDate date = startDate.plusDays(1); date.isBefore(endDate); date = date.plusDays(1)) {
ResultSetFuture resultSetFuture = session.executeAsync(findByCreateDayAndCmId.bind(date, cmId).setReadTimeoutMillis(60000));
futures.add(resultSetFuture);
}
futures.add(session.executeAsync(findByCreateDayAndCmIdAndTimestampGreaterThanEqual.bind(startDate, cmId, startDateTimestamp).setReadTimeoutMillis(60000)));
futures.add(session.executeAsync(findByCreateDayAndCmIdAndTimestampLessThanEqual.bind(endDate, cmId, endDateTimestamp).setReadTimeoutMillis(60000)));
for (ResultSetFuture future : futures) {
try {
ResultSet rows = future.get();
Iterator<ConversationDetail> it = mapper.map(rows).iterator();
while (it.hasNext()){
results.add(it.next());
}
}catch (Exception e){
System.out.println("Exception1 " + e.getMessage());
}
}
}catch (Exception e){
System.out.println("Exception2 "+e.getMessage());
}
return results;
}
