catalog_category_product Indexer is taking hours

Indexer: catalog_category_product is taking huge amount of time

Category Products index has been rebuilt successfully in 03:25:32

Sometimes it fails with errors:

Base table or view not found: 1146 Table 'catalog_category_product_index_store{storeId}_tmp' doesn't exist

or

Could not acquire lock for index: catalog_category_product

Note that the current batch size for indexer is 100K

<type name="MagentoCatalogModelIndexerCategoryProductActionFull">
        <arguments>
            <argument name="batchRowsCount" xsi:type="number">100000</argument>
            <argument name="batchSizeManagement" xsi:type="object">MagentoCatalogModelIndexerCategoryProductBatchSize</argument>
        </arguments>
    </type>

What are the ways to optimize the indexer esp. catalog_category_product?