If I create site collection at http://server/sitecollection and if i create 3 sites:
http://server/sitecollection/site1 http://server/sitecollection/site2 http://server/sitecollection/site3

Are these sites subsites of the rootweb site or these are site collection subsites?

The reason that im asking is that im creating 10000 sites under http://server/sitecollection for a project that im working on. Time to create a site slowed significantly after i created 2500 sites. Now, im wondering if im missing something... or this behaviour is by design.

Any answers will help. Thanks

  • 1
    Is there a reason there are 10,000 sites in one site collection? Normally structures this deep are split across multiple site collections
    – Dave Wise
    Feb 13, 2012 at 17:15
  • we are doing lots of CAML joins between some logicly realated sites to get data (documents) visible to current user. Since we cant do CAML queries between site collections, we had to create all these sites under 1 site collection
    – bakre
    Feb 13, 2012 at 18:19
  • And that is an ideal reason for this structure!
    – Dave Wise
    Feb 13, 2012 at 18:29
  • well, that is one of the main reasons for this structure. we didnt wanted to run some custom logic to get data from multiple site collections, which would require custom database part for each user and map each user to sitecollection+site before querying the multiple sites... we thought, having 10000-15000 sites in one site collection it's not a big performance hit since MS limit is 250000
    – bakre
    Feb 13, 2012 at 18:45

1 Answer 1


Site collections do not have parents, they are always at an equal level in a web application. The URL /sites/ is a managed path under which site collections are created, the 'root' of the web application is a separate site collection.

(you can create a 'portal' which creates a logical link between site collections but there is no true hierarchy created here, only clickable links in the navigation. site collections remain separate entities when you tie them to a portal).

There is no documented number to the maximum number of site collections, however if it's slowing down, consider putting some on separate content databases, as this will greatly help backup and recovery procedures.

EDIT: I didn't read that document well, the documented limit of site collections is 250,000 per web application, but I personally think this is a soft limit, and if you have problems over this value the first thing MS will tell you to do is to move some of the site collections to another web app.

EDITEDIT: As I've came across this confusion before, I've decided to write a blog post about this distinction. You can read it here.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.