Fix max_statement_mem not enforced

[roseduan]

GUC statement_mem can not exceed the value of max_statement_mem.

Before change:

postgres=# set max_statement_mem to '500MB';
SET
postgres=# set statement_mem to '600MB';
SET

After change:

postgres=# set max_statement_mem to '500MB';
SET
postgres=# set statement_mem to '600MB';
ERROR:  Invalid input for statement_mem, must be less than
max_statement_mem (512000 kB)

Fixes #ISSUE_Number

What does this PR do?

Type of Change

• Bug fix (non-breaking change)
• New feature (non-breaking change)
• Breaking change (fix or feature with breaking changes)
• Documentation update

Breaking Changes

Test Plan

• Unit tests added/updated
• Integration tests added/updated
• Passed make installcheck
• Passed make -C src/test installcheck-cbdb-parallel

Impact

Performance:

User-facing changes:

Dependencies:

Checklist

• Followed contribution guide
• Added/updated documentation
• Reviewed code for security implications
• Requested review from cloudberry committers

Additional Context

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[leborchuk]

Maybe it is better to cherry-pick commit Throws ERROR when statement_mem is set to greater than max_statement_mem. greenplum-db/gpdb-archive@301c9a2 ?

Here the same has been done, but it's better not to rewrite code again, just cherry-pick the changes.

[roseduan]

Maybe it is better to cherry-pick commit Throws ERROR when statement_mem is set to greater than max_statement_mem. greenplum-db/gpdb-archive@301c9a2 ?

Here the same has been done, but it's better not to rewrite code again, just cherry-pick the changes.

Thanks, that sounds great! I will cherry-pick the commit.