Free space just disappears?????

[vladimi]

Hi all forum users,

I have clean installed new OS X Mavericks. When its finished, total space used was 12GB ( which is kinda weird, cause I read on here, and it normally takes up 8-10GB), I did not install any other applications or whatsoever. After 2 days, my DiskUtility shows that 16.5GB is occupied already. I did not download ANYTHING, except AdobeFash player.

So where did 4.5GB came from????

I am using internet in hotel, so I am worried if someone is using my mac somehow ( hacked into it distantly? )....

What can be the cause?

 

[teleromeo]

Most likely that space is used as virtual memory or sleep image.
You can use an application like WhatSize to inspect what exactly is taking disk space.

 

[simsaladimbamba]

To find out, where you storage capacity is being used, you can use the following free applications:

• DiskInventory X
• OmniDiskSweeper
• JDisk Report
• GrandPerspective

Maybe try a combination of several, if you still can't find the "missing" capacity.

 

[vladimi]

Hi guys,

Thank you very much for your replies.

What is virtual memory is used for? How can I know if its this or something else?

Thank you again

 

[simsaladimbamba]

Hi guys,

Thank you very much for your replies.

What is virtual memory is used for? How can I know if its this or something else?

Thank you again

Virtual Memory does not take up storage space, but if you have RAM intensive applications and not enough RAM available, some content of the RAM will copied to the storage device (HDD, SSD, Flash) to make room for more RAM, but that is called "Paging Out" or "Page Outs" or "swapping".
You can look that up in Activity Monitor under the MEMORY tab and SWAP USED. I guess, that will not be the case with you.

 

[vladimi]

Ok, so I run WhatSize, and OmniDisk Sweeper.

Omni shows that 13.5GB is used.

WhatSize shows 15.5GB used.

And private>var....is the largest, 4.6-5.0 GB respectively.

What is private then? Since I am not downloading anything there

 

[Bruno09]

Remember that if your Mac is a laptop, the "sleep image" file (used when the mac goes to deep sleep) has the size of your RAM, and always exists.

Thus, if your Mac has 4 GB of RAM, and if your new Mavericks OS occupies 8GB, total space used is : 8 + 4 = 12 GB.

If you have 8 GB of RAM ---> 8 + 8 = 16 GB.

Also, when you use your Mac for surfing, it creates a lot of new files (Safari pages previews, preferences files, etc, etc…)

WhatSize shows 15.5GB used.

Normal, no issue here.

 

[simsaladimbamba]

Ok, so I run WhatSize, and OmniDisk Sweeper.

Omni shows that 13.5GB is used.

WhatSize shows 15.5GB used.

And private>var....is the largest, 4.6-5.0 GB respectively.

What is private then? Since I am not downloading anything there

That is the location of the sleep image and swap files. As you have not mentioned, what Mac you have, we can only speculate, but the size indicates swap files, maybe even with a 4 GB sleep image file.
I guess you have not looked at Activity Monitor yet?

sleepimage – the Mac OS X sleepimage file explained