Hi,

As we know, we have a parameter avg_series_point_number_threshold=10000, which 
controls the maximum point number of one series in memtable can not exceed the 
threshold.
The main purpose of this configuration is solve the problem that if the number 
of point in one TVList is too large, it will take too much sorting time on 
query and flush. 

However, we recently got many feedback about when import historical data series 
by series, each time we insert a series with 10,000 points, then the 10,000 
points will form a tsfile. 
As a result, there would be a lot of small tsfiles after the data imported and 
the query efficiency is not as good as we expected.

Therefore, I would like to change the default value of this parameter to 
100,000. Two reasons about it. One, change the threshold larger can improve the 
efficiency of the scenario
above. Besides, it may not have any side effect to enlarge the number on other 
application scenario. Someone may remember, this configuration was actually 
introduced to IoTDB
before the memory control mechanism added. After we have the memory control, 
this threshold almost cannot be reached except the importing historical data 
scenario. 

This is the first step to solve the problem. We may need to find a more smart 
strategy to replace this parameter in the future.

How do you think?

BR,
Haonan Hou


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