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I'm planning to buy a new PC and I am thinking about using an SSD as the main disk. I'd also use a standard spinning disk and I'd mount it to /home.

To the people already using such a setup: does this induce a practical, noticeable enhancement in performance? I think that access times, rather than transfer rates, are the more useful feature of SSD's. I would like to know if they have a noticeable effect on a desktop installation of Ubuntu. Thanks in advance!

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4 Answers 4

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I think that access times, rather than transfer rates, are the more useful feature of SSD's.

That's certainly one massive improvement. Yes, the random-access time on my current and past SSDs have both been around 0.2ms. I upgraded from a fast mechanical disk (WD Raptor) and the boot-up on the SSD just blew me away. It does so much, so fast.

Of course ureadahead and other tools aim to make the boot-up as linear as possible (they essentially write a whole load of files that are needed at boot into one sequential block) but that's where the SSD's second benefit comes in: huge maximum-throughput speeds.

The sustainable transfer speed of my first SSD (OCZ Agility) was around 200MB/s. My new SSD (OCZ Revodrive - a PCI-E card) tops out at around 540MB/s. The Revodrive X2 reaches somewhere around 750MB/s. There are solutions that scrape 2GB/s but they're prohibitively expensive for most people.


Like your plans, I started with my entire home being bind-mounted onto a RAID array on mechanical disks. This was good and is technically much more secure but it does limit the ability for the computer to really fly.

Browsers and other database heavy applications (feed readers, email apps, etc) need fast access to the disk to work well. You might want to weigh up how valuable your data really is, and if some of it can perhaps stay on the SSD and survive with the occasional backup.

Keeping various often-accessed files (like the Firefox database or gnome settings) on multiple mechanical disks is also pretty noisy. I have quiet, fairly slow disks and even I find it annoying when loading something causes 4 disks to start clunking away (I have 4-way RAID5). Perhaps this is something that you learn to appreciate after living with a silent SSD for a while.

These days the only things that are on the RAID are users' documents. That is ~/Documents, ~/Music, ~/Photos, ~/Vidoes and (for disk space reasons more than anything) ~/.wine. Everything else either gets an occasional backup (Firefox/F-Spot/etc SQLite3 databases once a day). I try to run a monthly proper ~/ backup (excluding the stuff that is on RAID) once a month, but I'm yet to cron it.

This is a good compromise for me. I get a lightning fast computer and all my really important data is quite safe and all my semi-important data gets backed up regularly.

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  • Thanks Oli for you reply! I'm also thinking about mounting /var on the spinning disk to lower the number of writes, and setting the commits times to 60 seconds.
    – motumboe
    Feb 1, 2011 at 9:39
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Speeds up boot and application launch significantly. I keep my main /home on it as well and mount the bulk storage elsewhere so that when I'm not using it, that disk can spin down.

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  • My laptop hd died. I ran off a usb drive for a while. Finally bought an ssd to replace the hd. Boot time went from 7m with usb to 20s with ssd.
    – djeikyb
    Jan 31, 2011 at 22:33
  • 7 minutes?! Sheesh. I' get about 10 seconds on the ssd and 20 seconds on my now 7 year old first gen WD 10k rpm two drive raid0.
    – psusi
    Feb 1, 2011 at 0:00
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My setup is an SSD for / and a spinning disk for /home and it's great for boot time, installation of packages, and launch time of applications.

I detailed my set up here for a similar question.

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Boot time increases visibly. With Dell Inspiron Mini 10v (1011), the difference is up to 10 seconds compared to a HDD (click on bootchart links to see it graphically).

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  • 5
    Decreases, surely?
    – Oli
    Feb 1, 2011 at 14:47
  • Look at the link, for the entry 20100406, the boot time with SSD is 17,30s and 24,91s with HDD.
    – papukaija
    Feb 1, 2011 at 20:12
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    Right, that's a decrease in boot time with an SSD. Feb 6, 2011 at 22:26

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