If I add a new link in my website, should I genrate again site.xml file for google we

There's no need to make a new one. Google bots will crawl that link eventually.

Sitemaps are pretty much worthless unless:

1) you have a brand new site with NO inbound links but want to let the search engines know your site exists.
2) you have a poorly written site that uses technologies that prevent the URLs from being crawled, or
3) you have a site with hundreds of thousands or millions of URLs and you want to prioritize which URLs are most important and should be indexed first with the <priority> element in the sitemap.xml

Other than those 3 reasons, using a sitemap is worthless. It doesn't cause Google to crawl you any more often than THEY think your site should be crawled. It doesn't cause them to index any more URLs from your site than THEY think should be indexed. They simply use your sitemap (if you have one) to help them discover URLs that they can't find by crawling and to prioritize which URLs are more important than others (and should be indexed before others).

No you don't have to create new site map.

Its better that you add all of your links in your sitemaps. But you can put them all only in one sitemap.

No need at all it will be waste of time.

I agree. Do not use a site map file. Maintaining a site map work took us a lot of time and generated several errors in the crawl report. It is quite normal that we add new pages or remove the existing pages and sometimes we change the URL of pages.

Thanks.

its majority, it will automatically included together with google they will crawl it for indexing.

For me, you must update your sitemap once you added new pages.

It is advisable to keep the latest sitemap.xml on your website. You can update the file in a periodic manner. Read this SeoMoz blog post to understand the importance of sitemaps.

the observation ended up being outweighed by the impact we saw with the increased indexation rates of sites that employed this tool.

You are helping the crawlers to index more content by using Sitemap.
If new links are found in the sitemap, then googlebot or any other crawler will index the content faster. Good for you. :-)

You are helping the crawlers to index more content by using Sitemap.
If new links are found in the sitemap, then googlebot or any other crawler will index the content faster.

Totally untrue. Google's not going to index your URL faster because you update your site map. And unless you have a VERY crappy site, they will be perfectly capable of locating the new page on your site. So they do not get more of your content indexed if your site is crawlable.

The only thing sitemaps do is when Google (not you) decides they want to crawl your site next, they will use it to help find URLs they might not be able to find otherwise (ONLY for sites that have crawlability issues) and to prioritize which to include first. If they only want to index 10 of your site's URLs, submitting a new sitemap is NOT going to make them index 11. The priority field however can be used to help them decide which 10 URLs are most important in your eyes to be indexed first. But they may still decide to not index one/some of your higher priority pages because some of your lower priority pages might have more links so they might index those instead.

Originally Posted by francis84

For me, you must update your sitemap once you added new pages.

Me too!

Originally Posted by crescendo

If I add a new link in my website, should I genrate again site.xml file for google we

It is a better idea but not necessary. Google will automatically find your new link.

The sitemap is just a list of your pages in a solo page layout. When a caller goes to your site they can right to use the sitemap to discover any pages that they are concerned in viewing. typically the sitemap is to benefit the people who stay your site and give them a quick and easy way to navigate your site.

Sitemaps are next to useless.

As one poster said,
You can prioritize links.

Thats about it.

The only "MAIN" use for them is so search engines can find pages on your site that they would otherwise not find,
IE: Javascript links.
Member only pages , Hidden dirs etc.

You must update sitemap every time you add an extra page on your site.

Through Sitemap, search spiders get information about pages of your site. It would be better if you update the sitemap every time you add a page.

Originally Posted by pankajsharma

You must update sitemap every time you add an extra page on your site.

Through Sitemap, search spiders get information about pages of your site. It would be better if you update the sitemap every time you add a page.

No, It is not necessary.

No there is no need create a new .xml file as the google crawler will easily crawl that link. So don't worry.