On Windows platforms code was previously added to zero-fill each newly allocated data file in order to work around an issue described in this Windows Knowledge Base article. As this issue only applies to Windows 7 and Windows Server 2008 R2, the zero-filling unnecessarily slows down file allocation on other, unaffected Windows versions, namely Windows 8 and Windows Server 2012.
Slower file allocation on Windows platforms.
The fix is to restrict the zero-filling of newly allocated files to only the affected Windows versions.
All recent production release versions up to 2.4.9 are affected.
The fix is included in the 2.4.10 production release and the 2.5.5 development version, which will evolve into the 2.6.0 production release.