Optimum Frequency to generate new sitemaps for large sites

Hi, I just upgraded to Sitemap 3.0 and vBSEO 3.6.0 (great products from a great company BTW).

I have optimized the sitemap config in accordance with recommendations found here in this forum. 275,586 URLs have been submitted to Google and they have indexed 229,629 of those, according to webmaster tools.

When I looked at the status of the individual .gz sitemap files yesterday, google was still saying 0 indexed for a few of them. So, I assumed they were just moving thru all the URLs and would eventually get to everything.

I have a cron job set to rebuild the sitemaps every morning. I am wondering if daily sitemap rebuilds are a good idea for a site this large? Should it be every 2 or 3 days to allow google to catch up with what I submitted before? It *seems* like google has not processed all the URLs, then it gets notification of a new sitemap build and has to start all over before it finished the last ones. Thus, the ones at the proverbial end of the process are never being indexed.

Seeking advice from the SEO experts.

We suggest once a day. If you have a VERY new-thread heavy site, perhaps twice a day max. But there are load concerns with running it often.

OK thanks! I just discovered that it was running as a vB scheduled task in addition to my cron job, so I guess it was running twice. I disabled the vB Task.