If an application writes data to the flash array in small blocks, such as 5KB, only four bytes per each 5KB of data is needed. Static regions in the flash must be moved frequently. Sector deadlocks must be avoided. Wear-leveling is inherent to VBF operation in that data written to the flash array is never updated to the same location. Instead, an entire erase sector is written before an erase operation is performed on the data.
Static regions can severely shorten the life of the flash array.
For example, if a 1MB flash array contains a 600KB application and uses the other 400KB to log and keep track of a database, the flash array would effectively contain a 600KB static region. VBF handles the issue of static regions somewhat differently than some commonly-used methods. Some systems attempt to prevent the creation of static regions by stringing data throughout the flash array while others use a statistical model to perform garbage collection processes on sectors that have no actual discarded data blocks. In contrast, VBF maintains some statistics on overall sector usage as a means of actively detecting static regions in the flash array. Another wear-leveling issue is that of avoiding deadlocks.