Storing 1 million records in XML to improve performance

We have a very large user populated table with record count exceeding 1 million. This table is associated with other relational-tables with one-to-many relationship.
We also have close to 10,000 concurrent query/update happening to this table. To improve performance we are planning to switch over to XML.

Following will be the approach:
1.Create one XML file for each user containing user data (1 million XML FILES). These will be stored in the Hard Disk.
2.Absolute path of the XML file would be used to parse the user data. This absolute path will be known well in advance for the program.
3.The XML files would also be frequently updated.

Can you kindly tell us if this approach of switching from database to XML would actually improve performance?