Spring Batch tables cleanup takes forever

Question

For an application based on Spring Boot and relying on a PostgreSQL 9.6 database, I'm using Spring Batch to schedule a few operations which must take place every n seconds (customizable but usually ranging between a few seconds and a few minutes); as a result, at the end of the day a lot of jobs are performed by the system and a lot of information are persisted by Spring Batch.

The fact is that I'm not really interested in historicizing those jobs so, at the beginning, I used the in-memory version of Spring Batch to avoid any kind of persistency on such (to me) useless information.

However, in case of configurations with small n running on environments with low resources, this approach led to performance issues so I decided to try with the database way.

Unfortunately, those tables grow quite fast and I would like to implement a cleanup procedure to get rid of all data older than, for instance, a day.

Here comes the pain: in fact, even if nothing is locking those tables (so, the main application is down and noone is interacting with the database) it takes forever to clean them and I really cannot understand the reason why.

Spring Batch (4.0.1) provides the following PG script to generate those tables:

CREATE TABLE BATCH_JOB_INSTANCE  (
    JOB_INSTANCE_ID BIGINT  NOT NULL PRIMARY KEY ,
    VERSION BIGINT ,
    JOB_NAME VARCHAR(100) NOT NULL,
    JOB_KEY VARCHAR(32) NOT NULL,
    constraint JOB_INST_UN unique (JOB_NAME, JOB_KEY)
) ;

CREATE TABLE BATCH_JOB_EXECUTION  (
    JOB_EXECUTION_ID BIGINT  NOT NULL PRIMARY KEY ,
    VERSION BIGINT  ,
    JOB_INSTANCE_ID BIGINT NOT NULL,
    CREATE_TIME TIMESTAMP NOT NULL,
    START_TIME TIMESTAMP DEFAULT NULL ,
    END_TIME TIMESTAMP DEFAULT NULL ,
    STATUS VARCHAR(10) ,
    EXIT_CODE VARCHAR(2500) ,
    EXIT_MESSAGE VARCHAR(2500) ,
    LAST_UPDATED TIMESTAMP,
    JOB_CONFIGURATION_LOCATION VARCHAR(2500) NULL,
    constraint JOB_INST_EXEC_FK foreign key (JOB_INSTANCE_ID)
    references BATCH_JOB_INSTANCE(JOB_INSTANCE_ID)
) ;

CREATE TABLE BATCH_JOB_EXECUTION_PARAMS  (
    JOB_EXECUTION_ID BIGINT NOT NULL ,
    TYPE_CD VARCHAR(6) NOT NULL ,
    KEY_NAME VARCHAR(100) NOT NULL ,
    STRING_VAL VARCHAR(250) ,
    DATE_VAL TIMESTAMP DEFAULT NULL ,
    LONG_VAL BIGINT ,
    DOUBLE_VAL DOUBLE PRECISION ,
    IDENTIFYING CHAR(1) NOT NULL ,
    constraint JOB_EXEC_PARAMS_FK foreign key (JOB_EXECUTION_ID)
    references BATCH_JOB_EXECUTION(JOB_EXECUTION_ID)
) ;

CREATE TABLE BATCH_STEP_EXECUTION  (
    STEP_EXECUTION_ID BIGINT  NOT NULL PRIMARY KEY ,
    VERSION BIGINT NOT NULL,
    STEP_NAME VARCHAR(100) NOT NULL,
    JOB_EXECUTION_ID BIGINT NOT NULL,
    START_TIME TIMESTAMP NOT NULL ,
    END_TIME TIMESTAMP DEFAULT NULL ,
    STATUS VARCHAR(10) ,
    COMMIT_COUNT BIGINT ,
    READ_COUNT BIGINT ,
    FILTER_COUNT BIGINT ,
    WRITE_COUNT BIGINT ,
    READ_SKIP_COUNT BIGINT ,
    WRITE_SKIP_COUNT BIGINT ,
    PROCESS_SKIP_COUNT BIGINT ,
    ROLLBACK_COUNT BIGINT ,
    EXIT_CODE VARCHAR(2500) ,
    EXIT_MESSAGE VARCHAR(2500) ,
    LAST_UPDATED TIMESTAMP,
    constraint JOB_EXEC_STEP_FK foreign key (JOB_EXECUTION_ID)
    references BATCH_JOB_EXECUTION(JOB_EXECUTION_ID)
) ;

CREATE TABLE BATCH_STEP_EXECUTION_CONTEXT  (
    STEP_EXECUTION_ID BIGINT NOT NULL PRIMARY KEY,
    SHORT_CONTEXT VARCHAR(2500) NOT NULL,
    SERIALIZED_CONTEXT TEXT ,
    constraint STEP_EXEC_CTX_FK foreign key (STEP_EXECUTION_ID)
    references BATCH_STEP_EXECUTION(STEP_EXECUTION_ID)
) ;

CREATE TABLE BATCH_JOB_EXECUTION_CONTEXT  (
    JOB_EXECUTION_ID BIGINT NOT NULL PRIMARY KEY,
    SHORT_CONTEXT VARCHAR(2500) NOT NULL,
    SERIALIZED_CONTEXT TEXT ,
    constraint JOB_EXEC_CTX_FK foreign key (JOB_EXECUTION_ID)
    references BATCH_JOB_EXECUTION(JOB_EXECUTION_ID)
) ;

CREATE SEQUENCE BATCH_STEP_EXECUTION_SEQ MAXVALUE 9223372036854775807 NO CYCLE;
CREATE SEQUENCE BATCH_JOB_EXECUTION_SEQ MAXVALUE 9223372036854775807 NO CYCLE;
CREATE SEQUENCE BATCH_JOB_SEQ MAXVALUE 9223372036854775807 NO CYCLE;

By respecting the references precedence, I try to cleanup those tables by executing the following deletions:

delete from BATCH_STEP_EXECUTION_CONTEXT;
delete from BATCH_STEP_EXECUTION;
delete from BATCH_JOB_EXECUTION_CONTEXT;
delete from BATCH_JOB_EXECUTION_PARAMS;
delete from BATCH_JOB_EXECUTION;
delete from BATCH_JOB_INSTANCE;

Everything is ok with the first 4 tables but, as soon as I reach the BATCH_JOB_EXECUTION one, it keeps like 30 minutes to remove a few hundred thousands of rows. Even worse, after deleting everything from the first 5 tables, the last one (which is now linked to nothing) takes even more.

Can you see a reason why this simple operation takes so long to complete? I mean, of course it has to check for constraints violations but it seems however unreasonably slow.

Plus, is there a better way to use Spring Batch without wasting disk space with unnecessary jobs information?