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Other Storage on Mac eats up your Disk Space? Here are 6 tricks
In Finder, I've noticed that if I duplicate some. This file size discrepancy does not happen for all. Here are some examples:. Now I am new to Macs, and after I noticed this file size discrepancy problem, I discovered that. So I thought maybe the duplication process did not copy all of the contents of the original. So the duplication process worked perfectly, and it therefore seems to be a problem with Finder reporting file sizes.
I also checked the sizes of the directories in Terminal, using the "du" command, and that too shows discrepancies in sizes between the original and duplicate directories:. Also, it's not just. So can anyone explain why Mac OS X doesn't seem to report directory sizes correctly? Is it a bug hard to believe for something so simple , or am I missing something being a new Mac user? What is most strange about this is that Finder has no consistency. I just made 2 duplicates of the GarageBand. Finder displays every single duplicate with a different size:.
Also note that "GarageBand copy 3.
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That has to be a bug in Finder. At least it says all the duplicates are the same size, but they're not the same size as the original. The differences came from different reasons: different ways of counting, different tools, compression and what looks like a bug. The first difference in size you see seems to be a bug in the Finder. The file sizes shown by the Finder are somehow calculated in real time and cached in. It then shows that size as greyed in the Finder windows, grey meaning the Finder knows the content has changed since it's last size calculation but it hasn't recalculate it yet.
The only way I've found to make it recalculate correctly the size is by deleting the. If you don't delete the. Maybe waiting some time hours, days, reboot, You can also see this thread which reports same kind of behavior. Then, let's consider the du tool. At first, I thought the difference we see could be explained by the difference between logical and physical sizes of items being copied. Logical size is the real size of the item, meaning every single bit of information it contains added up together. Physical size is the size of the item on the disk, where each information bit is written on a disk sector.
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For example a file containing a single character would end up having a 1 byte logical size, but a bytes or even bytes physical size when actually written to disk. This is explained into more details in this other thread. You can see that the size reported by du is always bigger or, exceptionally, the same as the original. This is because of file system and disk space fragmentation.
When you copy over a file actually here a bunch of files, as an Application is a directory new sectors are being allocated on the disk and, as fragmentation occurs , the number of blocks used is usually higher than that of the original item. Some people call that File Slack. Now, back to the Finder. If you open up the get info window of the Applications you duplicated, you'll see that the Finder is actually reporting both the Logical and the Physical size of the item you selected.
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Which then makes sense. You'll even be able to compare the Physical size reported by the Finder and the one reported by du if you do a bit of math. Why doing some math? Those are the IEC binary prefixes which should be used to calculate and display units of digital information. But, actually, I'm not sure File Slack is involved here, there's something else. Then, when files are copied using standard tools, compression is not used anymore as a default, to be backward compatible. If you want to keep compression on those files, you need to use the ditto command instead of cp or any Finder action.
This is explained in this review. Here is the output of copying iTunes. You'll see that ditto makes the Application exactly the same size, preserving compression, where cp doesn't. And you can even remove the binary for the arch you don't need, then reducing the whole size :. Thanks to DanPritts for his answer on my complementary post. The easiest way to see it is to duplicate a large application bundle, then show the contents and delete a huge file from within.
The space will not recover. The file is still huge.
As an example, a typical 1 hour TV show downloaded in iTunes takes up around 1 GB, and so the entire 6 series of Lost takes up well over Gigabytes on your hard disk. A summary of each category is shown, which may help you to decide how best to reclaim disk space. The most obvious and easy way to free up some space is to empty the Trash.
Remember that individual applications such as iMovie, iPhoto and Mail each have their own Trash, so empty those frequently too. In Mail, trash and junk emails can be automatically deleted by setting the relevant options in preferences. Applications can take up large amounts of space. Some applications use caches to store various bits of information, but these files can grow very large over time and consume valuable disk space. A typical example is Safari which has an Internet cache to save it re-downloading content from frequently visited websites.
Most applications store their caches in one of the following two folders:. Cache files can be safely deleted, because an application will just create a new one when needed. Pruning your media libraries is a great way to save space.
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Compressing a file will normally reduce the disk space it needs, so you might then decide to keep it on your hard disk or move to external storage. The number of emails in Mail and the disk space they need can grow enormously over time, especially because mails with attachments can be very large indeed. Old emails can be archived and attachments removed to save space. To help keep the size of your mailbox as small as possible, remove attachments from messages and save them to local folders on your Mac, which can then be dealt with in the normal manner i.
However, periodically clearing out your old and unused files, media, and applications is a good habit to get into. This could include identical iTunes content and other media, as well as identical files that simply have different filenames. There are a few ways to remove duplicates:. I've been passionate about Apple ever since I bought my first iPod followed by a white polycarbonate MacBook in Roland's Google Profile. This site uses Akismet to reduce spam.
Learn how your comment data is processed. Quite ridiculous — something is wrong in the state of Apple — always some other Apps fault. And to then be expected to purchase another App to put it right is a joke. As far as iTunes goes — it must be the worst piece of software ever designed — a complete mess.
Tip 3 is not quite right. The asterisk wildcard does not work in Spotlight. Then it will work as described.