Thursday, November 12, 2009


I've been asked more than a few times on what I think about HDD (spinning mechanical hard drives) vs SSD (solid state drives).

I've noticed a difference between the two during heaving editing. Dropped frames, longer seek times etc...but my experience is pretty limited, too limited to form a complete opinion yet. I did however run across this nice introductory article on the differences and limitations of SSDs compared to HHDs.

The two points that really caught my eye are:

As a primer for the following, we mention two major issues with SSDs:

1) HDDs can be put into storage for a decade and then, provided that there are still systems out there that support the interface, they can be plugged in and the data will be readily accessible. NAND flash-based SSDs will lose their data over time, even if they are powered down and in storage.

2) HDDs will show some degradation of performance over time, primarily relating to filling up of the outer diameter tracks and fragmentation of the drives’ media but a defragmentation will restore the performance since it is defined by spindle speed and media area density and those parameters never change. SSDs will show some initial extreme performance but degrade rapidly after heavy usage.


Jon said...

HDDs can also lose data over time if not used. I experienced this a couple of weeks back with a drive that hadn't been used for 18 months.

Jeffrey Di Lullo said...

You may want to check out this article:

Jeffrey Di Lullo said...

Walker Ferox said...

The Larry Jordan article seems a bit hard to swallow. As HD's get larger and larger the " replenish any magnetic signals that are starting to fade" that he mentions by a surface scan would take longer and longer.

HD's are set to spin down over time usually. I find it hard to believe that they spin up, touch, "replenish" or move a file that's the HD has not been specifically told to access.

What about files that are rarely if ever touched? How does a plugged-in HD know to "replenish" it (or a bit) if it's not been told to look there?

Sure OS X does some defrag on the fly, but only with small bits of data, not yet, for whole files.