Open Software Solutions

A heavily fragmented file in an NTFS file system volume may not grow beyond a certain size because of limitations in structures that are used to describe the allocations.

In this scenario, you may experience one of the following issues:

• When you try to copy a file to a new location, you receive the following error message:
  In Windows Vista or in later versions of Windows
  The requested operation could not be completed due to a file system limitation
  In versions of Windows that are earlier than Windows Vista
  insufficient system resources exist to complete the requested service
• When you try to write to a sparse file from the Application log, Microsoft SQL Server may log an event that resembles the following:
  In Windows Vista or in later versions of Windows
  Event Type: Information
  Event Source: MSSQLSERVER

  Description:…
  665(The requested operation could not be completed due to a file system limitation.) to SQL Server during write at 0x000024c8190000, in filename…

  In versions of Windows that are earlier than Windows Vista
  Event Type: Information
  Event Source: MSSQLSERVER

  Description:…
  1450(Insufficient system resources exist to complete the requested service.) to SQL Server during write at 0x000024c8190000, in file with handle 0000000000000FE8 …

When a file is very fragmented, NTFS uses more space to save the description of the allocations that is associated with the fragments. The allocation information is stored in one or more file records. When the allocation information is stored in multiple file records, another structure, known as the ATTRIBUTE_LIST, stores information about those file records. The number of ATTRIBUTE_LIST_ENTRY structures that the file can have is limited.

We cannot give an exact file size limit for a compressed or a highly fragmented file. An estimate would depend on using certain average sizes to describe the structures. These, in turn, determine how many structures fit in other structures. If the level of fragmentation is high, the limit is reached earlier. When this limit is reached, you receive the following error message:

Windows Vista or later versions of Windows

Versions of Windows that are earlier than Windows Vista

Compressed files are more likely to reach the limit because decompressing and compressing a file increases fragmentation significantly. The limit can be reached when write operations occur to an already compressed chunk location. The limit can also be reached by a sparse file. This size limit is usually between 40 gigabytes (GB) and 80 GB for a very fragmented file.

For files that are not compressed or sparse, the problem can be lessened by running Disk Defragmenter. Running Disk Defragmenter will not resolve this problem for compressed or sparse files.