[mdlug] SSD - flashcache or bcache

[Ingles, Raymond]

> From: Garry Stahl

> The cost of SSD or flash is the main reason I have not looked into either for my personal machines.
>  Frankly good old disk technology gives you the best return on the dollar.

Well, sure. RAM is fantastically expensive compared to disks, too; even worse than SSDs. I mean an SSD is around ten times as expensive per GB, but RAM is around a *thousand* times as expensive as disk per GB! We should replace all our RAM with disks, computers would be a lot cheaper. :-)

Except... RAM is also a lot *faster* than disk. As anyone knows who's ever gone deep into thrashing swap. That's why we have RAM at all... many things can't wait for the read head to get in the right position and the rotating platter to finally spin around under it.

Putting the right things on an SSD can *dramatically* speed up a computer. As I'm finding out by experience with my new SSD. Booting and launching apps is *much* zippier now. I'm not storing the bulk of my files on SSD - I have terabytes on spinning platters - but putting the OS and app binaries on SSD really makes things hustle.

SSD is just a tool, and sometimes it's the right tool for the job. That said, I did wait until the price/performance ratio got to a satisfactory level for my needs. A 32GB drive would not have been enough for me, but after a couple years, I could get over 200GB for the same price.