Solved SSD space not being shown correctly?

I just installed a pretty clean install of Windows 8 Pro (I used the upgrade, but I did the upgrade immediately over top of a clean windows 7 install). It is installed on an intel SSD. I haven't installed any applications or added any documents, or files. However, when I go to file explorer and right click on my drive it shows that I've used 69GB of space on the SSD! That's after doing disk cleanup and removing the previous windows files and temporary upgrade files. I couldn't believe Windows was taking up 69GB, so I investigated further.
If I select the drive in file explorer and then select every folder displayed, and then right click and select properties, then it only comes up as about 13GB.
Is there a known problem with Windows 8 computing space useage on SSD drives?

No, and Windows is not giving you the wrong information. Your drive does have 69GB allocated.

As for why, that could be a number of reasons. First, you have to understand that SSD's work a little differently from normal drives. When you delete files, the drive has to later do a cleanup to return everything to you. This is called TRIM (despite being capitalized, apparently it's not an acronym). You TRIM your drive by using Windows Defrag on the drive (Seriously!).

Windows setups a scheduled task to run this TRIM optimization once a week, so in normal use you would probably never notice it. But since you deleted a large number of files in the cleanup, it's more obvious.

Second, There are hidden files and folders which do not show up when you select all folders and view their properties. For example, the pagefil.sys, which is typically 2x the size of your memory (if you have 8GB, then it will be 16GB). Another file is Hiberfil.sys, which will also be the size of you memory (another 8GB lost).

Third, there are hidden folders used for drive snapshots and system restore, these can have as much as 10% of your drive's size in system files.

Thanks for your reply Mystere. I Trimmed the drive as you suggested, but that didn't make any noticeable difference. I also turned off system restore, and went into disk cleanup including the options for cleaning up system files and deleting shadow copies. Still no real savings to be found.

For example, the pagefil.sys, which is typically 2x the size of your memory (if you have 8GB, then it will be 16GB). Another file is Hiberfil.sys, which will also be the size of you memory

Click to expand...

Ah, this must be the culprit. I put 32GB of RAM in this beast. So those files you mentioned must be chewing up quite a bit. Is there anything I can do to limit how much space those .sys files use?

Well, that depends. Do you use hibernation? If not, you can disable the hiberfil.syss.

Hibernate - Enable or Disable - Windows 7 Forums

That's for Windows 7, but the process is the same.

You can also change the size of the pagefile.

Virtual Memory Paging File - Change - Vista Forums

Thanks again! I did both of those things and now my used SSD space is down to 14GB. Much better! I put the maximum paging file size to what windows recommended - 7GB (it was set automatically to 32GB). I set the initial paging file size to 2GB. With 32 GB RAM though, I doubt if I'll ever need to use virtual memory (unless I'm misunderstanding how that works).

I thought it was not good to defrag a SSD drive?

SSD drive will read a the same speed so defrag is not needed. Defrag a drive will cause it to reach it's end of life sooner.

That's what I have read.

Correct, it is generally not good to defrag a SSD.

However, the Windows 8 function is named "optimize disk." For a mechanical disk, that function performs a defrag. For a SSD, the Optimize function performs a TRIM. And TRIM is good for a SSD.

I would definitely not run any third-party defrag utilities on a SSD, as they probably would do an actual defrag and not a TRIM.

How often should the Optimize be done?

Windows 8 optimizes disks automatically. The default setting is weekly. I use the defaults.

To examine or change the schedule, open My Computer, select a drive, right click and select Properties. On the Tools tab, click on the Optimize button. From there you can change the schedule.