Handwritten Text Recognition for manuscripts and early printed texts
Manage Lists and Libraries with Many Items - EPC Group
1. Manage lists and libraries with many items
Applies to: Microsoft SharePoint Server 2010
No matter how big or small, lists and libraries are vital to your use of SharePoint 2010 in many ways. But
when a list or library has a large number of items, you need to carefully plan, organize, and account for
how data is accessed. By planning and using key list and library features, you can ensure that you and
other users quickly find information without adversely affecting the performance of the rest of your site.
NOTE The performance of any SharePoint site, especially one that contains lists and libraries with many
items, is directly affected by decisions made when setting up and planning a SharePoint site. Find more
information about SharePoint performance and capacity planning on Microsoft Technet.
Overview of lists and libraries with many items
SharePoint 2010 supports very large lists and libraries. The following table summarizes the specifications
and limits for lists and libraries that contain many items.
FEATURE MAXIMUM LIMIT
Number of items in a list or library 50 million
Size of an individual file item or item attachment 2 Gigabytes
As you can see, you can store a lot of data and files in lists and libraries. But if a query or database
operation exceeds a resource throttle or limit, you may be blocked from doing this operation because
accessing that many items could adversely affect other users of the site. Fortunately, there are a set of
straightforward strategies and basic features you can use to achieve the results you want to prevent you
from exceeding these throttles and limits. All users can circumvent the limit during a dedicated time
window, and with appropriate permission you can also use a higher limit through code.
WHY IS 5,000 SUCH A MAGIC NUMBER?
To minimize database contention, SQL Server often uses row-level locking as a strategy to ensure accurate
updates without adversely impacting other users who are accessing other rows. However, if a read or
write database operation, such as a query, causes more than 5,000 rows to be locked at once, then it's
more efficient for SQL Server to temporarily escalate the lock to the entire table until the database
operation is completed. Note that the actual number is not always 5,000, and can vary depending on your
site, the amount of activity in the database, and your site's configuration. When this lock escalation occurs,
it prevents other users from accessing the table. If this happens too often, then users will experience a
degradation of system performance. Therefore, thresholds and limits are essential to help minimize the
impact of resource-intensive database operations and balance the needs of all users.