google bot rel="nofollow" how long to stop following

I just added rel="nofollow" to some links.

Anyone know how l开发者_如何转开发ong it takes for google to stop following after "nofollow" is added to a link? I added an hour ago and still see them crawling the "nofollow" links.

It might be the case that it won't stop following your rel="nofollow" links. According to Wikipedia:

Google states that their engine takes "nofollow" literally and does not "follow" the link at all. However, experiments conducted by SEOs show conflicting results. These studies reveal that Google does follow the link, but does not index the linked-to page, unless it was in Google's index already for other reasons (such as other, non-nofollow links that point to the page).

From Google's Webmaster Central:

Google's spiders regularly crawl the web to rebuild our index. Crawls are based on many factors such as PageRank, links to a page, and crawling constraints such as the number of parameters in a URL. Any number of factors can affect the crawl frequency of individual sites.

Our crawl process is algorithmic; computer programs determine which sites to crawl, how often, and how many pages to fetch from each site. We don't accept payment to crawl a site more frequently. For tips on maintaining a crawler-friendly website, please visit our webmaster guidelines.

Using Google Webmaster Tools, you can see the last time it crawled your website and if the links are still showing in the searches, they may be conflicting as per @Bears post.

That depends on many things. Google's databases are massively distributed, so it may take a while for the change to propagate. Also, it may take the crawler some time to revisit the page where you added the nofollows - again, this is computed by some closed Google algorithm. In the worst cases, I've seen tens of days without the indexes getting updated; best case, few minutes. The modus would be a few days. Be patient, young Jedi ;)

I am keeping track of around 7000 pages on how google visits them. Yes it keeps following the pages even if I put the nofollow thing but for a while. It will crawl the same page a couple of times before it finally removes it. So it'll take time.