duckdb: JDBC Memory leak on CentOS 7.7

What happens?

Memory leak on CentOS 7.7,window is ok. There is a memory leak when executing multiple queries on CentOS 7.7

To Reproduce

We’ve written a minimal reproduction and shared it as a GitHub repository. The reproduction runs for a specified period of time.

Environment (please complete the following information):

OS: CentOS 7.7
DuckDB Version: 0.3.3
DuckDB Client: jdbc
] Have you tried this on the latest master branch?

Python: pip install duckdb --upgrade --pre
R: install.packages("https://github.com/duckdb/duckdb/releases/download/master-builds/duckdb_r_src.tar.gz", repos = NULL)
Other Platforms: You can find binaries here or compile from source.

Have you tried the steps to reproduce? Do they include all relevant data and configuration? Does the issue you report still appear there?

About this issue

Original URL
State: closed
Created 2 years ago
Comments: 16 (5 by maintainers)

Most upvoted comments

@Mytherin The JDBC driver does not use Query. Everything goes through Prepare and Execute.

conn->Query(TABEL_DROP_SQL);

I ran this example (that I feel is close to the JDBC calls) and each query uses almost a 200 Bytes of extra memory.

#include "duckdb.hpp"
#include <iostream>

using namespace duckdb;

int main() {
	DuckDB db(nullptr);
	/* Connection con(db); */
    auto con = make_unique<Connection>(db);

	con->Query("create table t (id int8, texty varchar)");
	con->Query("insert into t values (1, 'uiae')");

    int i = 0;
    long total = 0;

    while (true)
    {
        auto stmt_ref = con->Prepare("select texty from t where id = 1;");
        vector<Value> duckdb_params;
        auto res_ref = stmt_ref->Execute(duckdb_params, false);
        
        i++;
        total++;

        if (i == 1000)
        {
            std::cout << "Total: " <<  total << std::endl;
            i = 0;
        }
    }
}

Hopefully someone can confirm this or point to a problem with the example.

Jens-H on Jun 16, 2022