Data fragmentation is a common issue that affects both performance and available disk space . For an Exchange database an online defragmentation process is in place automatically that reduces fragmentation and hence enhance performance.
Although online defrag reduces fragmentation in don’t regain unused space which is called “Whitespace” . For previous versions – prior Exchange 2010 – event 1221 at application log – which indicates the whitespace for each database during scheduled online maintenance .
For Exchange 2010 the concept has been modified. As Exchange 2010 introduced the new 24/7 maintenance mechanism – enabled by default –
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