The amount of individual calculated permission items grow by the number of memberships

Queries being built up using query access are exploding by their statement length using hundreds (sometimes thousands) of placeholders.

This case is true when the number of groups grow accordingly. Usually a user has one membership per group anyway.

Another problem is the following query being built within \Drupal\group\QueryAccess\EntityQueryAlter::doAlter:

<?php
// ...
$group_relationship_data_table = $this->entityTypeManager->getDefinition('group_relationship')->getDataTable();
$plugin_ids_in_use = $this->database
  ->select($group_relationship_data_table, 'gc')
  ->fields('gc', ['plugin_id'])
  ->condition('plugin_id', $plugin_ids, 'IN')
  ->distinct()
  ->execute()
  ->fetchCol();
// ...
?>

Since the table may grow by hundreds of thousands of records, the distinct query affects performance. It gets noticeable when this method is called within one record up to 100 times (which is possible when rendering Views configurations).