A hard drive is a device for permanent or long-term storage in computers.

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48
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6answers
7k views

Do Macs need to be defragmented?

I don't see any application to defragment my Mac (running OS X). Is defragmenting not necessary for Mac OS X? If so, why not?
46
votes
7answers
144k views

Is it safe to delete ~/Library/Caches?

Is it safe to delete the file Caches, in the Library of the Mac OS X Hard Drive? It's a pretty big file, 3.56 GB, Caches reminds me of logs i don't need or browser cookies. Is it safe to delete the ...
34
votes
3answers
20k views

What are the differences between journaling HFS+ and non-journaling HFS+?

I'm about to format an external hard disk drive (HDD). What are the key differences between journaling HFS+ and non-journaling HFS+? Apart from the fact that one has journaling and the other does not,...
29
votes
2answers
15k views

What is the difference between a “sparse disk image” and a “sparse bundle disk image”?

What are the differences between sparse and sparse bundle disk images?
28
votes
3answers
32k views

How do I get detailed SMART disk information on OS X (Mavericks or later)

I'm trying to get a detailed SMART status report on the drives in my Mac. I'm not talking about "Verified," I'm talking about the detailed report that's about 100 lines long listing all the vital ...
26
votes
8answers
84k views

How to eject my external drive when my Mac refuses because of Spotlight?

I have plugged an external disk to my Mac. Now, I want to eject it. But my Mac stubbornly refuses and says that an application may be using the disk. I have not launched any app neither opened any ...
24
votes
8answers
40k views

How to check if my HD is case sensitive or not?

How can I get information if my HD format is case sensitive or case insensitive? I want to make sure my Mac running Mountain Lion has a case sensitive file system.
21
votes
4answers
18k views

MBP SSD upgrade - which settings to change?

After replacing the harddisk drive in MacBook Pro with a Solid State Disk I am wondering which settings I should change and how. Thinking of things that are supposed to protect the SSD like ...
17
votes
8answers
18k views

Time Machine ridiculously slow after El Capitan upgrade

I recently updated to El Capitan, and told Time Machine to backup. It got stuck on Preparing Backup for hours, so I stopped it, deleted the InProgress file, rebooted and tried again. After ~30 mins, ...
17
votes
5answers
2k views

Does the use of SSD give one a dramatic performance boost?

I use Mac book pro 15", and it's time to buy a new one. For HDD, now I see a new option of SSD, which is pretty expensive. I can expect shorter boot-up time and faster access of files, but I'm not ...
16
votes
7answers
35k views

What format for my external drive allows use with Mac and Windows?

How can I use my external hard drive on Mac OS so I can modify/edit files on both OS's: Mac and Windows? How should I format it?
16
votes
4answers
7k views

FAT or exFAT or NTFS

I recently brought Western Digital's Passport Essential, and will be using with my MacBook (running Snow Leopard), MacBook Air (running Lion) and Windows 7 Desktop. I should be able to read-write data ...
15
votes
4answers
141k views

How do I make the hard drive visible in the Finder?

On OS X Lion I don't see the hard drive in the Finder and I seem to have no permission to create a folder under / from terminal. I know I can do this if I activate the root user, but I need to be ...
14
votes
2answers
2k views

Is defragmenting an SSD drive a bad idea?

I have heard that defragmenting SSD drives will shorten the life span of a drive. Just wondering if there is any truth to this and if so could someone elaborate as to why this happens.
14
votes
1answer
14k views

What is com.apple.bird? Why does it grow so big?

Trying to clean up their hard disk, some users discover ~/Library/Caches/com.apple.bird is pretty big. In the order of too many Gigabytes. What is it?
13
votes
6answers
57k views

What is the best way to clone a disk between two Macs?

What is the best way to clone a disk between two Macs? I ask this every couple years or so and every time I get the same answer. "Use Carbon Copy Cloner", they say. But the unfortunate fact is that ...
13
votes
3answers
83k views

Disk Utility won't Unmount HD for formatting

I have two internal drives in my 27" iMac (10.8.5). An SSD system disk and a 1TB SATA drive. The HDD has been acting up recently, very slow performance, bad behavior etc. Tech Tool Pro and Disk ...
13
votes
2answers
6k views

How can I disable the 2nd hard drive in my 27" iMac?

I have an 2010 27" iMac with an SSD and a regular hard drive. Now that I've been using the machine for some time and have not come close to filling the SSD, I'd like to disable the spinning hard drive ...
12
votes
3answers
7k views

How do I eject the Time Machine backup drive automatically after each backup?

How do I set Time Machine to eject my external Time Machine backup drive automatically after each backup?
12
votes
1answer
5k views

Replacing SuperDrive with secondary storage?

I'm familiar with the OWC Data Doubler, a kit which allows you to remove your Macbook's SuperDrive and replace it with secondary storage. What alternatives exist for this product? A complete answer ...
12
votes
3answers
60k views

How can I delete a partition (coreStorage logical volume?) from the Terminal?

I finally understood why Disk Utility will not change the partitions on my HDD, even though I added the most recent one myself (maybe significant: to test Yosemite DP) with it. Now I see it says it ...
11
votes
3answers
10k views

Is it necessary to eject external drives before logging out, restarting, or shutting down?

Is it necessary or recommended practice to eject external drives before logging out, restarting, or shutting down? (The drives are not being unplugged.) BTW, I am aware that I need to eject my ...
11
votes
7answers
24k views

How can I keep my fan from staying at full speed after replacing the hard drive?

I replaced a hard drive in a 2011 iMac (Core i7), though it was a standard hard drive and didn't have a location for the S.M.A.R.T. cord. (Or at least I think that's what it was.) Since then, the ...
11
votes
10answers
66k views

Macbook HD “Other” all the Sudden Almost Full

As you can see in the below image, my HD "Other" category is almost full. A couple of days ago, I randomly kept getting a popup saying that my disk was almost full. Then I went in and noticed the ...
11
votes
4answers
2k views

What are some tips for replacing my MacBook Pro hard disk with SSD?

I would like to replace my MacBook pro hard disk with an SSD, without reinstalling everything. I am looking for your experience on good SSD drive models that have good performance at a fair price ...
10
votes
2answers
11k views

Is File Vault 2 whole disk encryption or whole partition encryption?

Can I use File Vault to encrypt only some of the partitions on my disk (so that I can still have unencrypted and Windows partitions on the same disk), or does File Vault encrypt the whole disk so that ...
10
votes
2answers
20k views

How can I get Automator to mount a network volume?

I am writing an Automator "script" that rsyncs media on my 10.6.3 MacBook Pro to my Ubuntu 10.10 HTPC. I can make Automator run my shell script for rsync commands, but I can't make Automator mount the ...
10
votes
5answers
69k views

Unable to format / erase hard drive

I have an external HD that died on me a while ago and I'm trying to see if I can format / erase it to start using it again. The disk does not show up in Finder but I can see it in Disk Utility. When ...
9
votes
7answers
2k views

What are the best disk cloning tools?

Money is no object. I want a bit for bit perfect copy of a hard drive/partition which is bootable (is either possible) to be used in a backup regimen. I have heard of some tools but your ...
9
votes
4answers
12k views

What are the sector sizes on Mac OS X?

I read on the HFS Plus Wikipedia page that the default sector size on a Mac is 512 b. However, I also read that Macs support 4kb sectors. How can I determine which I have, 512 b or 4 kb sectors? I ...
9
votes
10answers
14k views

What is the benefit of using flash memory in the Macbook Air?

I don't understand why Apple does not use SSD drives in the Macbook Air like some other manufacturers to (e.g. Asus, Samsung). The technical specifications of the Macbook Air on Apple's website never ...
9
votes
3answers
2k views

How do I not accidentally eject external drives?

I have a Mac Mini with a few external drives connected that I use as a home server. Normally the Eject buttons next to the drive icon are really handy as they let me eject an external drive very ...
9
votes
4answers
2k views

Which process is periodically writing to the disk?

Even when I am not doing anything on my Mac, I see a lot of Disk IO: "Data Written per Sec" in Activity Monitor showns continuous writes: Is this normal? Why would some process continuously write? ...
9
votes
2answers
6k views

Will I damage my HDD if I transport my MacBook in sleep mode?

Is it safe to carry MacBook with HDD in a bag while it has been put sleep? I.e. I know there are some risks of hard disk drive damage if one tries to shake them or rotate them while they're working. ...
9
votes
3answers
4k views

What happens when you remove (or lose) the SSD from a Fusion Drive?

After storing data on a Fusion Drive, is it possible to downgrade your Mac to use the hard drive (HDD) by just removing the solid state drive (SSD)? In particular, I was wondering what happens when ...
9
votes
5answers
68k views

What is the best free hard drive diagnostics app for Mac OS X?

My MacBook Pro (described below) fell 5 feet while it was powered on. Would the sudden motion sensor be able to turn off the hard drives in time? Also, can anyone recommend the best (free) hard drive ...
9
votes
2answers
9k views

How do I resize OS X main partition when I already have other BootCamp partitions?

Short story: partition resizing using Disk Utility fails because MediaKit reports no such partition when I try to shrink it. I also tried the same while booting from the DVD, same result. Details: ...
9
votes
4answers
4k views

Why have 5 different iMacs developed corrupt OS X partitions when the physical drives are fine?

I'm a tech for my local school district and we are having some problems with our iMac Multimedia Lab. Over the past nine months, 5 of the 22 iMacs have suffered from filesystem corruption. The only ...
8
votes
3answers
1k views

How can I upgrade MacBook Pro disk space?

I have a fairly new MBP with 256 GB of SSD as disk space. I am running out of disk space now. Most of it is being used by Pictures and Music and I have done all the cleaning I could. What's the best ...
8
votes
2answers
6k views

How to fix Disk Utility, About This Mac, and Finder that disagree on hard drive space usage?

Has anyone seen this issue and know how to fix it? Look at the free space reported by running "Get Info" on my hard drive (Macintosh HD) in the Finder, "About This Mac" from the Apple Menu, and Disk ...
8
votes
3answers
12k views

How can I mount an encrypted disk from the command line?

When I type diskutil mount disk3 in the terminal, it says Volume(s) mounted successfully. However, the disk is not mounted and I can confirm this by opening the GUI of Disk Utility.app and also the ...
8
votes
4answers
3k views

iMac inconsistenly hanging and showing beach ball

This past week, I've been having constant problems with my 2007 Aluminium iMac (2.4GHz, 3GB memory, 320GB HDD). I've been downloading using Transmission, and when (sometimes) stopping or starting a ...
8
votes
2answers
722 views

How can I move my data to the new harddrive?

So I am planning to upgrade my Macbook pro's harddrive to a SSD. I don't know much Mac OS X tools, so I was wondering if anyone could let me know how I can copy my entire harddrive (including OS) to ...
8
votes
2answers
3k views

Is there a way to limit external hard-drive random spin-up?

I have 2 external USB drives connected to my iMac running 10.7.3. One is designated completely for Time Machine use and the other I use for data. (Nothing but a bunch of JPGs on that one.) The first ...
8
votes
4answers
14k views

9GB com.apple.coresymbolicationd file in Caches

I'm trying to free up disk space, and I came across this: I've read reports of a 600M file, or a 1GB file but never something like this. Is it safe to delete or does rebooting frequently help ...
8
votes
1answer
489 views

Don't wake up external hard disk when saving to internal one

My problem is that I have an external hard drive connected to my Mac. Since it is only used for backup purposes, it is sleeping most of the time. However if I now want to save something (e.g. a ...
8
votes
1answer
5k views

Extremely slow write speed to encrypted external drive on Mavericks

Writing to a fully encrypted USB flash drive on Mavericks is extremely slow. The drive model I used for testing was a Kingston DataTraveler Ultimate 3.0 G3 (64 GB). I tested transfer speeds by ...
8
votes
1answer
1k views

How can I tell whether a drive is asleep?

Is there an application or command-line utility for Mac OS X to query a hard-disk to see if it is 'asleep' or 'awake' right now? (i.e. as controlled by Energy Saver / pmset disk sleeping preferences). ...
7
votes
4answers
900 views

Will a cloned hard drive function exactly as the original?

If I buy a new hard drive and clone my original onto it (using Carbon Copy Cloner or something similar), will my computer function exactly the same as it did before? Will things like licensed programs ...
7
votes
2answers
3k views

How to make an expanding compressed encrypted disk image?

I'd like the following setup: A DMG file sits on my HD, taking up only the space of the contents, or perhaps only the space of the contents compressed. If I double-click on it, I need to give a ...