Google’s Webmaster Tools provides web site tools and reports to provide you the knowledge that how the search engine views your site and also to make the process easier for the search engine to index the pages of a site. For webmasters, Google Webmaster Tools is a no-charge web service by Google.
Today, a patent granted to Google has one of the tools included within the Webmaster Tools that allows the webmasters to set different crawling rates on their website for the crawling programs of Google and optimize visibility of their websites. From the patent, the description does not limit itself to that tool and also describes other processes involving the webmaster tools.
• Generation of XML sitemaps
• How XML sitemaps may be crawled by the search engine
• The verification process used by owners to claim ownership of their site to use Webmaster tools
• Setting a preferred version of a domain such as without or with a “www”
• Setting a crawling rate for a site
• Informing the search engine of a move of a site to a new domain
Therefore, it has tools that enable the webmaster to:
• Check and set the crawl rate
• Submit and check a sitemap
• List internal and external pages that link to the site
• Generate and check a robots.txt file
• View statistics about how Google indexes the site
• Set a preferred domain
• See what keyword searches on Google led to the site being listed in the SERPs, and the click through rates of such listings
So, I hope Google Webmaster tools will be beneficial for you.