A 4x11cm cylinder of polycrystalline silicon, the material used to make solid state hard drives (image via ).
Some work-in-progress visualizations of the physical location of specific files on my hard-drive, being made as part of my residency at Bell Labs. The above two images are details, showing files (in red) and empty space (in gray); each little square is one 512-byte sector.
This current version is visualizing an 8GB thumb drive. The prints are approximately 36×60″ (91×152 cm) so each individual sector can be seen. The hope is to do a version of my laptop’s hard-drive, which will require a much larger print or set of prints.
The goal of these visualizations is not analytics or troubleshooting – instead, I’m very interested in the abstraction between us, our computers, and our data. We take a photograph of something in the world and store it on a physical drive (even the end-point of the cloud is still a physical object). Once stored on a hard-drive, digital objects, however ephemera-seeming, continue to exist as physical ones and zeroes, magnetic charges of a specific size and intensity. These visualizations are about trying to unpack and see my personal data on that level.
But there is a significant disconnect between myself and my computer, and the actual data on my hard-drive. It turns out that drives contain a specialized chip that handles requests to read and write data; the algorithms that actually retrieve and set data are a closely guarded industrial secret. These chips act as a black box between the user and their data, rendering a detailed picture of the exact location of the bits that make up our digital lives almost impossible. This obscurity is especially prevalent in SSDs, due to the way they store data. This post on Aleratec puts it a finer point on it:
…unlike traditional hard-drives where the physical location of each bit of data is known and constant, the physical location of data in an SSD is highly abstracted from the outside world. Whereas each Logical Block Address (LBA) on a [hard-drive] always points to the same physical location, the physical location to which an SSD LBA points changes often.
My images then are a best-guess of where the actual data is stored, extracted using digital forensics tools. Below is the full image of the drive – click on it for a full-sized view.
I was fortunate enough this week to visit the Stevens Laboratory for Multiscale Imaging, home to the campus’ electron microscope. Generously, they offered for me to make some images on the microscope. I brought in small (12mm square) samples of a hard-drive platter (above), a small 3D print and a CD-R. More images after the break; a full set of images and process photos here.