More investigation on the defragmentation products
After evaluating Diskeeper and PerfectDisk further, I found something to say. One point about PerfectDisk is that, it takes about 60MB of RAM, with its UI being around 15MB and its engine around 40MB. Diskeeper, however, is different. Its engine takes about 20MB and its UI taking 70MB. Based on this, I’d say Diskeeper is more preferable, because the engine runs in the background all the time.
Another difference is that, the PerfectDisk analysis pass takes longer than Diskeeper does. And Perfect disk has some features that are not aimed at disk performance, such as duplicate file finder, which I almost never use (not even free ones).
And, although I said sometimes Diskeeper Home edition doesn’t do defragment if the remaining disk space is too low, this is the rare case anyway. Often the disk has ample space to do defragmentation. In this case, Diskeeper is quite fast (I have not tested PerfectDisk thoroughly, though). In the background, Invisitasking works great, making the computer always responsive–it doesn’t do defragmentation when you have activity on it. If the disk is really full, at least I can use free third-party tools, such as JkDefrag, to solve such issue.
And what’s more important, Intelliwrite does prevent 80% of the fragments! It pre-allocates disk space wisely and thus avoid files from being “crowded” together. As I tested by doing the following: leave the free disk space below 40G. Copy a 10G folder with around 10000 files to a new one, and at the same time copy a 20G archive to a new one. Because they’re done in parallel, chances are that the 20G archive would be split, with files filling at the spaces between its fragments. With Intelliwrite, the fragments are still kept low (even if such fragments exist), and thus the disk performance is not affected much.
So finally, this year’s choice is still Diskeeper.
Diskeeper Professional, on the other hand, with its “Consolidate Free Space” feature, was very good at avoiding excessive fragments, because Intelliwrite works very well with ample contiguous free space.
After trying PerfectDisk 12.5 home edition on a physical computer. My impression is: not good enough for me.
The drive was 15G in size, with more than 73% filled with data. Tried Diskeeper 9, it defrags the files, but couldn’t consolidate the free space well. As PerfectDisk analyzes, it tells me the free space fragmentation is more than 90%. Then I ran a SMARTPlacement (a technology in PerfectDisk) defragmentation on it, it finishes within about three times of the time taken by Diskeeper. I think now it should be fine. To my surprise, the files are not fragmented, but the free space fragmentation is still near 90%. I think maybe I should use the Consolidate Free Space method. I tried it, and now, the free space fragmentation goes even higher–above 95%! I think, this has stopped me from wanting to buy it for the next a few years, because it didn’t fulfill its statement (it compared to Diskeeper and said that it was better, but I couldn’t tell it from my run).
The PerfectDisk installer, on the other hand, doesn’t ask me whether to replace an existing msvcr100.dll and instead directly skipped copying it. However the version I had was not compatible with PerfectDisk. I had to manually install one that is compatible.