Is the Time Finally Right For Hybrid Hard Drives?

a_hanso writes "Hard drives that combine a traditional spinning platter for mass storage and solid state flash memory for frequently accessed data have always been an interesting concept. They may be slower than SSDs, but not by much, and they are a lot cheaper gigabyte-for-gigabyte. CNET's Harry McCracken speculates on how soon such drives may become mainstream: 'So why would the new Momentus be more of a mainstream hit than its predecessor? Seagate says that it's 70 percent faster than its earlier hybrid drive and three times quicker than a garden-variety, non-hybrid disk. Its benchmarks for cold boots and application launches show the new drive to be just a few seconds slower than a SSD. Or, in some cases, a few seconds faster. In the end, hybrid drives are compromises, neither as cheap as ordinary drives — you can get a conventional 750GB Momentus for about $150 — nor as fast and energy-efficient as SSDs.'"

Is this significantly different from SRT?

[pathological liar]

I don't imagine it is. Anandtech found it wasn't that difficult to evict stuff from the cache you actually wanted [anandtech.com]. Not to mention that if you start copying anything especially large (your MP3 collection, or installing a couple games from a Steam sale, say) you nuke the cache and are back to mechanical HD performance.

Personally, I prefer to do it manually. Stuff I want to load fast (Windows, applications, games, my profile folder) sit on an SSD. Bulk data sits on a mechanical drive.

Prices!

[Shifty0x88]

Not only are SSD prices going down, but traditional hard drives are going UP! (At least for the short term)

Prices taken from Newegg.com:

Seagate Barracuda XT 3TB is $399.99 (used to be a lot cheaper)

Seagate Barracuda 1TB SATA III:

About a year ago: On sale for $60, regular $70

Now: $149.99

I think now is the time of the SSD and the hybrid drive is just not worth the price

And considering this drive is retailed at $239.99 and a regular mechanical 750GB drive is between $69.99(Hitachi Deskstar) and $179.99(Western Digital Black) there is no reason to buy it.

Just go buy a small SSD and a regular mechanical drive and do it manually

Re:movies and video

[Jane Q. Public]

I admit this is slightly off-topic, but I recently saw a 32GB Class 10 SD card for under $30... and it got me remembering back to when -- not as long ago as some might think -- it took an hour to transfer the contents of one 10MB... that's MB not GB... 5.25" HDD, which cost $400, from one machine to another over the network.

Re:It'd better happen quick then

[AmiMoJo]

SSDs typically have large memory caches, where as HDDs are still stuck around the 32MB mark. With RAM so cheap these days even the lowest end graphics cards are coming with 1GB, but not HDDs for some reason.

Re:It'd better happen quick then

[drinkypoo]

That's because it doesn't do anything good for hard drives. There was a paper about it some years ago, I'm too lazy to google it up, but even 32 MB is too much (I think the sweet spot was around 2 MB).

Having had the 2MB and 8MB versions of the same disk from Seagate that uses the same mechanism and having seen the 8MB disk be substantially faster, I'm pretty sure it's not 2MB.

Re:It'd better happen quick then

[swalve]

I agree. But the difference between 32 and 64 might not be so great. There is a limit to how much a HDD can predicatively read, and I have to think that the real world difference between caching writes isn't going to be all that much on a single user machine. What we will see, I believe, is drives that become smarter and have their own filesystem layer that obscures the LBA from the physical location on the disk. The machine says "write this data to block 43533224" and the HDD just starts writing to whatever free blocks are nearest to its r/w head, using the flash to store the map. It will then defrag itself during downtimes to optimize the locations. (Dear Seagate: if I really just invented this, please pay me.)