High swap consumption during database backup with mariabackup

We are experiencing a swap consumption problem when backing up our database. Every evening at 01am we run the mariabackup command and during the process swap usage rises sharply until it reaches 100% and only drops back to normal usage around 10am at best. The VM has an Alamalinux 8.4 OS, around 60GB RAM and a 4GB SWAP partition. Normal” resource utilization (excluding backup) is around 70-80% of RAM and 70-80% of SWAP. The vm.swapiness value has been set to 0, but this does not change the SWAP consumption. RAM usage remains fairly stable outside or during evening backups. Do you have any idea why SWAP is used so much during backups? Is this normal? Do you have any recommendations? --- after checking, it seems that the swap overconsumption is caused by the tar command issued after the mariabackup to archive the command result. Is there any way of obtaining a tar file directly from the mariabackup command? For your information: - the mariabackup command takes about 5 min, while the tar command takes about 1 hour. - the possibility of increasing the swap to 8GB should be tested. - in our context, deleting the swap partition is not possible for administrative reasons.