Hi Guys,

I have troubles with a Sharepoint list with unique permissions. I have done some testing and come to the following observations:

With the items (having unique permissions) count increasing, the load time for new and edit forms increases proportional. It seems that this is related to the number of items the current user has access to. For example a member of a particular group having access to all items experiences greater load time than another user that has access only to few items. With around 700 items the load time is 12 sec. With around 5000 items the load time is more than 1 minute. The server seems to not experience any performance issues CPU under 10%, no heavy disk or memory usage. I dont think I can scale up. Display form and views are performing relatively well.

What is the relation between new form and the number of security scopes the current user has access to?

How can the situation be improved? I have read many posts for people having lists or libraries with around 50 000 security scopes with acceptable performance.

Please advise.

 

• Edited by Rinshwind Saturday, June 27, 2015 5:47 PM

Hi Wendy,

I actually traced the issue at SQL level. Here is the problem:

SELECT TOP (@ThresholdRowCount)
            P.ScopeId,
            P.Acl,
            P.AnonymousPermMask
        FROM
            TVF_Perms_ScopeUrlLike(@SiteId, @ListRootEscaped) AS P

This seems to get executed on every NewForm.aspx request. I lowered the threshold in the web app throttling to 2000 and now the forms are loading in 5-6 seconds even with 5k unique permissions (down from 1,5 min!!!).

Now if anyone can explain what and why is going on here?

Hi,

We are currently looking into this issue and will give you an update as soon as possible.
 
Thank you for your understanding and support.

Best Regards,

Wendy

Hi Wendy, thanks for your replies.

Actually I found the reason. There is a self referencing lookup filed in the list - parent item. This is why SharePoint evaluates the items in the list on new/edit forms.

If I hide the parent item field the forms are loading instantly. 

I assume I cannot server side filter the lookup values OOB? This would be a good solution.

Also when the server is not loaded at all, it performs well with list items threshold of 2000. With 5000 the performance is not acceptable. If the server is loaded the load time is going to 20-30 sec. even with threshold of 2000. Can I get the threshold lower than 2000 somehow?

Regards,

Nikolay.