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There are mass storage drives that consist of a large HDD and a smaller part of flash memory. From the computer's point of view they act just as a normal hard drive, but internally the disk internally moves frequently used portions to the SSD part for performance increase. An example for this type of drive is the Seagate Laptop SSHD ST1000LM014.

Are there any reported performance increases compared to a pure hard drive when using Ubuntu (or any Linux distribution for that matter) or does the internal software of the drive rely on NTFS file system features? Since there are no additional drivers needed I do not expect software problems, but I could not find any reports of how this works. And googling for SSHD and Linux leads to no relevant results for obvious reasons.

PS: I hope you do not read this as a shopping recommendation. I am not looking for a specific product, but want to know whether drives with this concept are useful for Ubuntu systems?

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    Just to be clear, the scenario described above is for hybrid drives with the SSD and HDD built into a single physical drive. There is another similar technology where two separate SSD and HDD are used by Intel's proprietary protocol: SRT. Ubuntu (or any Linux) cannot use SRT.
    – user68186
    Nov 22, 2013 at 15:08
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    @user68186 Yes, I am talking about a single physical drive. Inmy case it would be a notebook drive, so there would not even be enough space for two separate drives.
    – Tim
    Nov 22, 2013 at 15:26

4 Answers 4

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Yes, they do increase performance. Particularly for commonly accessed data. The drives typically cache the most accessed data in the SSD portion of the drive, However, the performance increase might be small enough that you may not visually notice it. The drives don't rely on a particular file system. The firmware calculates based on raw block access.

The drives however, will not necessarily be as fast as a high performance 3.5" drive. I have a couple of Seagate SSD+HD drives, one in my workstation, and one in my PS3. I didn't choose it for performance, but power usage and size. I am sure the one in the PS3 is definitely faster than the original drive that came in it though. The download and install times for games seem to be much faster than previous, and compared to a friend's PS3 with the original drive.

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I have done similar change in my old dual-boot laptop, there was a 20-30% decrease in boot (50->40sec) and shut down time in Ubuntu 12.04, in windows the change was more dramatic, around half time needed to boot (from over 3 minutes to less than 1.5min)!

If you want to revive a laptop, I suggest you do it. My findings are with SATA-I controller, I suspect you get much better results if your laptop has more recent controller (SATA2/3).

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  • Thank you for the answer. My laptop is beyond revivability. I am looking for a new one and have the option to replace a 7200rpm HDD with a (larger) SSHD drive which has only 5400rpm but 8GB of flash memory. So 20% may be less than what I lose from the slower hard drive. Did your HDD have more rpm than the SSHD that was 20-30% faster or was this parameter identical?
    – Tim
    Nov 22, 2013 at 15:31
  • My old disk was at 5400 rpm (Western Digital HD WD2500BEVS2.5-inch 250GB) and my new disk is Seagate at 7200 rpm (Momentus XT 750 GB).
    – bob
    Nov 24, 2013 at 12:46
  • Aren't both of these normal hard drives without any SSD components?
    – Tim
    Nov 24, 2013 at 15:16
  • No, the new one is a hybrid drive, as dobey said, the most used parts of the operating system go to SSD portion, see seagate.com/internal-hard-drives/laptop-hard-drives/… for explanation.
    – bob
    Nov 25, 2013 at 7:33
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I have one HDD and two Hybrid drives and there is a huge difference in read and access times: Hybrid drives are the middle ground between HDD and

However, SSDs suffer from a type of failure rate where the drive could crash and die: no lost boot sectors; just dead. Being a memory based drive it suffer memory kinks like a static discharge or a power outage. If the electric shock to the drive is large enough, you won't just lose your data: it will be wiped clean with zero chance of recovery.

In a Hybrid drive, if the SSD cache of the drive dies due to some malfunction/accident the data can still be recovered because it just goes from being a hybrid drive to a normal HDD (on some models). In fact if it dies while you're using it, you might not even notice the SSD cache being dead, until you run a benchmark or read/write something large from/to the drive.

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My advice to you is to use an SSD 32/64 GB for your /boot and / partitions and an HDD for /home.

You can either buy an mSATA SSD (if your laptop supports it) or a 2.5" SATA SSD. In the second case you will need replace one of the drives with your CD-ROM.

This is how I run my laptop for 3 years and I have no issues so far. :)

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