Thin provisioning and short stroke

You know we’ve always liked to talk about the importance of free space consolidation, which in many ways is as important as file defragmentation in recapturing and maintaining fast PC performance. Today I wanted to address free space consolidation as it relates to thin provisioning and virtualization performance.

Some thin provisioning technologies utilize high water marking to determine the amount of physical storage to allocate as data is written to a volume. A volume with data written to a high LCN range will provision all storage up to that LCN. Thus, a file written to an LCN range starting at logical cluster 20,000 will see all logical clusters allocated up to that LCN, even if the entire starting LCN range from LCN 0 to LCN 19,999 is composed of free space. The result is the creation of significant amounts of storage bloat, even if the data written to a high LCN range is only written temporarily.

PerfectDisk is already known as the definitive leader in free space consolidation, which dates back several years. Even as others tended to downplay its importance and accuse us of overstating its importance, we knew, through exhaustive and ongoing testing, its merits. The basis of our free space consolidation technology is SMARTPlacement, our patented optimization engine technology which allows it to move data to lower LCNs during optimization. And now, with the growing popularity of virtualization has forced other disk defrag utilities to pay attention, and try to provide some level of free space consolidation into their multi-pass solutions.

While PerfectDisk has always and demonstrably show superior free space consolidation results (as evidenced by the largest chunks of contiguous free space), until now, all solutions have shared a common problem. That is, defragmentation can temporarily write data to a high LCN during optimization. Competitive solutions will make users aware of this impact, but do nothing to prevent it from occurring in the first place.

Raxco Software continues its tradition of offering superior free space consolidation with the introduction of a low LCN optimization method called “short stroking”. This technology greatly enhances PerfectDisk’s support for high water mark solutions, in that it can dramatically minimize or eliminate the impact of defragmentation on storage bloat. Depending on the storage implementation, this new technology can single-handedly eliminate the need to perform deduplication or to take volumes offline for shrinking. In fact, when used over time, short stroking can replace the need to dedup a volume entirely. When used in conjunction with StealthPatrol, PerfectDisk’s solution for automatic optimization, short stroking can serve as impact-free, on-the-fly deduplication.

Short stroking for better virtualization performance via virtualization defrag, and maximizing virtualization investments.

PerfectDisk 12 — coming soon.





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