Speeding up slow disks with SSD caching
Afterburner
Flash memory is fast but also expensive. Caching with Flash provides a way out: A smaller and cheaper SSD can speed up the disk.
Hard disks are inexpensive, and they have huge capacities, but they are also slow. Solid state disks (SSDs) are fast, but smaller and more expensive. If you combine the advantages of a hard disk with an SSD-based cache, you pick up a large performance gain at a reasonable cost.
An application generally does not want all the data at once; most of the data is in the state of being ignored most of the time. Caching lets you move the most frequently requested data to an exclusive, fast medium and leave the less-frequently accessed data on the cheaper but slower background medium.
The Linux environment has several tools that provide the necessary software to support hard-disk caching. Does it help to use an SSD-based flash drive as a cache for a traditional hard disk? We decided to find out. This article explores the possibilities for caching with the Linux caching tools Enhance IO and dm-cache. If you are new to the topic of caching, and you would like some additional information on choices you might have to make, see the boxes titled "A Little Cache Theory" and "How Flash Works."
[...]
Buy this article as PDF
(incl. VAT)
Buy Linux Magazine
US / Canada
UK / Australia
Subscribe to our Linux Newsletters
Find Linux and Open Source Jobs
Subscribe to our ADMIN Newsletters
Support Our Work
Linux Magazine content is made possible with support from readers like you. Please consider contributing when you’ve found an article to be beneficial.
News
-
Photoshop on Linux?
A developer has patched Wine so that it'll run specific versions of Photoshop that depend on Adobe Creative Cloud.
-
Linux Mint 22.3 Now Available with New Tools
Linux Mint 22.3 has been released with a pair of new tools for system admins and some pretty cool new features.
-
New Linux Malware Targets Cloud-Based Linux Installations
VoidLink, a new Linux malware, should be of real concern because of its stealth and customization.
-
Say Goodbye to Middle-Mouse Paste
Both Gnome and Firefox have proposed getting rid of a long-time favorite Linux feature.
-
Manjaro 26.0 Primary Desktop Environments Default to Wayland
If you want to stick with X.Org, you'll be limited to the desktop environments you can choose.
-
Mozilla Plans to AI-ify Firefox
With a new CEO in control, Mozilla is doubling down on a strategy of trust, all the while leaning into AI.
-
Gnome Says No to AI-Generated Extensions
If you're a developer wanting to create a new Gnome extension, you'd best set aside that AI code generator, because the extension team will have none of that.
-
Parrot OS Switches to KDE Plasma Desktop
Yet another distro is making the move to the KDE Plasma desktop.
-
TUXEDO Announces Gemini 17
TUXEDO Computers has released the fourth generation of its Gemini laptop with plenty of updates.
-
Two New Distros Adopt Enlightenment
MX Moksha and AV Linux 25 join ranks with Bodhi Linux and embrace the Enlightenment desktop.