New Shingled Hard Drive Reduces Cost ~38% But Reduces Speed, Interested?

Seagate has a new hard drive technology / series called Shingled Magnetic Recording. It claims to increase capacity at a much lower cost / bit basis.

Here is a video that shows how it does it:

The drives are starting to ship in 8GB capacities. As noted in ExtremeTech:

"an 8TB drive for $260 is pretty impressive in terms of cost-per-gigabyte — 3.25 cents per gig, to be exact. As it stands, the cheapest 6TB drives on Amazon or Newegg are around $280 — or about 4.5 cents per gig."

However, these drives are spec'd at 5,900 RPM and an average read/write speed 150MB/sec and Seagate is positioning them for archive.

So are you interested in this for video surveillance?

The read speed should actually be pretty fast. The write speed is the slow part here, hence why it is used for archive. This will have a niche market. People who cannot afford a lot of storage, but need a lot of storage.

The speed is not your worry here. It is the durability of this manufacturer. Pretty sure if you go the cheap route, you probably have no RAID configuration.

Have you found where they break down read and write speads? I checked 5 articles on this and they all had something like "read/write throughput of 150MB per second" but not a breakdown on the write side.

That's because Seagate is not likely to talk much about the write side, preferring to lump it in with the reads. Reason? Although not found it the video anywhere, shingling's 'breakthru' is to remove the guard area that normally exists between tracks. The guard area prevents writes on one track from bleeding thru to the next.

Without the guard area in place, it means that, depending on what data is already written, old data will often have to be rewritten with the new data, slowing down the whole process. They can perform ok if doing large sequential writes since they can minimize the inefficiency better. They are not good at random writes to say the least.

For security video, I would imagine they might work well, since the density is so high and since the write process is usually an orderly sequential large block transfer.

Here's a great article from anandtech that explains in more detail.

"the write process is usually an orderly sequential large block transfer."

How often is that the case? How does this vary by VMS? I geniunely don't know. I see some VMSes claim different approaches here.

Good call. I had seen it in an article (see chart) and didn't question it because it made sense. But although desired, it's seems not so easy to achieve with multiple streams and finite buffering.

Intransa for instance claimed to pull it off, and we know what happened to them...

Milestone on the other hand is pretty insistent that it can't be done in their Live DB, and that is the reason that their archive database drives don't have to be as fast, since they write/transfer everything big block sequentially.

So there's one place you could use them. :)

Who got the Intransa patent?

For example, Axxon claims a recent development for them to basically do this:

"AxxonSoft has developed its own file system SolidStore especially for storing video archives. The system is installed on a blank physical or logical drive, which is fully allocated to Axxon Next video archive. In developing SolidStore, it was taken into account that recording will only be sequenced in one direction (looping mode), and the newest data is written in place of the oldes"

we have had so many problems with Seagate in the past, massive issues.

Western Digital solved all these issues for us - the quality of WD is excellent.

I wouldn't touch these drives for video recording with a ten-foot pole

I would be interested in the drive as a data backup storage solution. Not for Vidoe

The existing SMR drive is really not suited to any use other than a true Archive/Cold Storage application.

I have not yet seen any benchmark testing, but I anticipate one of the internet bloggers will do so eventually. This will likely show the random write performance to be significantly lower than the conventional options.

See Seagate's notes, 1 and 2, found below the "Best Fit Applications" paragraph of the data sheet, found here:

Seagate Archive Datasheet

Thanks, Alan, good find.

Copying note 2 to make it easier for all to see:

"Archive HDDs are not intended for surveillance or NAS applications, and you may experience lower performance in these environments. For these applications, Seagate NAS HDDs and Seagate Surveillance HDDs are suggested for better performance and reliability."

More Data on a HDD equals longer rebuild times if in a RAID array (1, 5, 6) i.e. the recording system remains in a degraded state longer i.e. more prone to another disk failing during the rebuild time.