Cronjob - poor performance

One of our cron job that does batch processing of orders has poor performance because of high no. of database calls it makes.As the job has to handle huge no. of items, because of lazy-loading, it ends making db call even for fetching a single attribute which is proving to detrimental. Can some one suggest what would be the preferred approach to avoid these many db hits. If I cache the items upfront, will it help? will it store all attributes values as well in the cache?