My site contains around two hundred thousand (200,000) users , i am defining the users in sharepoint groups. But i came through some of the microsoft blogs , it says a sharepoint group can have only 5000 users per group. So how can i go ahead and solve this issue ? Also is it ok if i store all the two hundred thousand users in one group? My thinking was to creating a sp group with same permission progrmatically when a threshold limit of 5000 is reached . am i correct ? Also,i am not using user profile sync service , as the AD doesnt have defined proper groups.
You will probably run into issues if you add 5000 users directly to a SharePoint group. Specifically, you could run into the 64K ACL limit. That issue manifests itself in many ways in SharePoint and one obvious manifestation is that the crawl stops working. See the following posts for guidance as to limits and best practices:
Here's an official info that supports your version:
SharePoint Server 2010 enables you to add users or Active Directory groups to a SharePoint group. Having up to 5,000 users (or Active Directory groups or users) in a SharePoint group provides acceptable performance. The activities most affected by this limit are as follows:
Fetching users to validate permissions. This operation takes incrementally longer with growth in number of users in a group.
Rendering the membership of the view. This operation will always require time.
I think it's right to split users into the different groups. Maybe it also be heplful to create nested groups - then you will have to assign permissions to the top group only - there's no risk to forget any group in that case while assigning permissions.
UPDATE: Unfortunately there's no support for nested groups in SharePoint so my last suggestion is not applicable.