Adjustment of parameter storage_group_report_threshold

[yanze chen <ch...@gmail.com>]

Hi everybody,


Currently, we have a parameter
called storage_group_report_threshold(default value is 16M), which means
when a storage group report its memory usage.

If this parameter is too small, may report frequently, which may decrease
the insertion performance.

If this parameter is too large, may report not in time, which may cause OOM.



We want to change this parameter according to the memory allocated for
writing.



(1) Remove parameter: storage_group_report_threshold.

(2) Add a new parameter: write_memory_variation_report_proportion. If
memory cost of data region increased more than proportion of allocated
memory for write, report to system.


Some tests have been done and we think 0.001 is an appropriate default
value. https://issues.apache.org/jira/browse/IOTDB-4022


Any comments would be much appreciated.


Best,

-- 
Yanze Chen
School of Software, Tsinghua University