Is it possible to truncate this table by cron? It seems to be necessary because in few days the table's weight increases to about 10GB.
wow, this will broke all SEO Strategy. Do not do this.
Magento 1 have a bug in url-rewrites and regenerated urls on every product save (after editing) and create multiple variants of urls for single product.
You can use this module to fix it. https://github.com/riznmage/Rizn_FixUrlRewrites