Spring Batch tables cleanup takes forever - spring

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?