The batch tables are purged after every verification, and if non-zero are always coupled. The default table sizes should be configured, as otherwise they start at 1 byte and expand (mremap) at a default 5% rate from there. But once expanded they don't contract in allocation until node stop, so it's pretty efficient. I initialize to 10MB each. That are empty at shutdown after a complete sync. However they always start back up as configured, which could be optimized. Really we want them to physically shrink to 1 byte each after the node is current/recent, and stay that way at startup.