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One of the reasons that some folk partition hard drives is that certain parts of the hard drive are supposed to be faster than others. Considering that HDDs are a serial access medium, partitioning, in addition to creating logical partitions, also map to a particular physical set of clusters/blocks on the hard drives

Now, with SSDs, its a whole different ballgame - wear leveling would rely on data being writable anywhere on disk, and with serial access, fragmentation has less of an effect

So.. do partitions on SSDs correlate to physical sectors on a disk like HDDs, or is it abstracted away at a higher level?

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  • "Considering that HDDs are a serial access medium ..." - check a good computer textbook, and you'll find that disk (and drums) are "random-access block" devices. Tape (magnetic and paper) are considered sequential devices. The salient characteristic is whether the unit-of-transfer (sector for disk & record for tape) can be accessed directly without having to read other sectors/records. "serial access"? The fact that disk tracks are only one bit wide is irrelevant; computer mag tape is typically 9 data-tracks wide, yet it is still a sequential-access device.
    – sawdust
    Sep 13, 2011 at 5:11

2 Answers 2

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In order to know this, you should check how wear leveling works.

Where do writes to a specific partition go?

In both dynamic and static wear leveling, a map is used to link Logical Block Addresses (LBAs) to the SSD memory. Thus, any write that you do to the SSD can get placed anywhere on the SSD...

You can see it as some kind of extra interface between your OS and your SSD, which just translates locations into other locations. Towards the OS there is just no difference. However, if you were able to look past the map you would see a lot of data scattered around, like a really fragmented disk!

What will prevent that I write more than the partition can contain?

The OS does this, as a partition only has a limited amount of LBAs.

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The only read speed difference I'm aware of with spinning hard drives is the seek time, the time it takes the arm to get to where you want to be. Seek time doesn't apply to SSDs as they are much more like a RAM stick, one that doesn't lose state when it loses power. I don't see why SSDs couldn't have partitions, but it would reduce the ability of the drive to share out the pain of writing.

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    .. most of the answer doesn't seem to be relevant to this question, except for the last sentence, which frankly should be a comment as it's entirely speculative. -1
    – DMA57361
    May 8, 2011 at 12:33
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    I doubt the last sentence. A write to a SSD can go to any location on the SSD. Partitioned or not. The wear leveling is precisely the same.
    – Hennes
    Dec 1, 2016 at 12:44

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