Tutorial of Nereids minidump

Minidump is a basic dump file for Nereids optimizer which arms
to replay problems and used as unit test tool for developers.
It include minimal necessary informations for Nereids optimizer
to replay a scenario in Optimizer.

Save minidump file

In two cases fe would save minidump file

when query throw an exception
when use ‘set enable_minidump=true;’ switch by User

File structure of minidump file

Minidump files would save in $DORIS_HOME/log/minidump path
and named by queryId like: c9bf82b70ce34c28-8d281e31412f3ee6.json
File structure of minidump file includes:

key	Value
Sql	original sql string
SessionVariables	sessionVariables different than default
DatabaseName	database name
Tables	schemas in table, partition info and some table properties
ColocateTableIndex	table distribute informations
ColumnStatistics	all ColumnStatistics in table
Histogram	all histogram information in table
ParsedPlan	plan after parsed in json format
ResultPlan	plan after all optimized in json format

Use of nereids_ut.sh

When we want to use this shell, we need to go to output/fe/minidump path
Now only one parameter is allowed for this shell which is directory
of minidump files like $DORIS_HOME/log/minidump

cd output/fe/minidump
./nereids_ut.sh --d $minidump_files_path

The running reports can be found in output/fe/minidump/log
which is minidump.out