Samsung ships the world's highest capacity SSD, with 15TB of storage • Hacker News Board

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#21

Post by userbinator » Fri, Mar 04, 2016, 1:40 AM UTC

The 15.36TB PM1633a drive supports one full drive write per day, which means 15.36TB of data can be written every day on a single drive without failure over its five-year warranty.

In other words, assuming good wear leveling, each bit can only be rewritten ~2K times, which is actually quite low for endurance... the capacity is high and they're using that to hide the fact that it's low, but if this was e.g. SLC flash with 100K endurance, you'd be able to write 50x more.

No mention of retention either, which makes me think SSDs today are more for temporary nonvolatile not-quite-RAM storage and not for more permanent applications.

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#22

Post by userbinator » Fri, Mar 04, 2016, 1:43 AM UTC

Animats wrote: post #9

It's awe inspiring to see fifteen terabytes of solid state storage in that little box.

What's more amazing is that it's still a long way to go compared to biological storage: https://news.ycombinator.com/item?id=4396931

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#23

Post by altcognito » Fri, Mar 04, 2016, 1:51 AM UTC

userbinator wrote: post #21

The 15.36TB PM1633a drive supports one full drive write per day, which means 15.36TB of data can be written every day on a single drive without failure over its five-year warranty. In other words, assuming good wear leveling, each bit can only be rewritten ~2K times, which is actually quite low for endurance... the capacity is high and they're using that to hide the fact that it's low, but if this was e.g. SLC flash…

SLC and MLC endurance aren't much different: http://hothardware.com/news/google-data-center-ssd-research-...

To reach a full rewrite a day, that's like 200Mb/s consistently over the span of a 24 hour day. If your loads/usage looks like this, you're probably expecting your drives to fail and are ready to replace them.

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#24

Post by dcip6s » Fri, Mar 04, 2016, 1:58 AM UTC

Anyone care to take a guess how much the 15TB version will cost?

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#25

Post by scurvy » Fri, Mar 04, 2016, 2:01 AM UTC

Why SAS and not NVMe? You can buy all NVMe enclosures/servers now.

Is this solely aimed at replacing drives in existing enclosures? Not much good there as most of them will be SAS6. They'll still work, but not nearly as fast as SAS12 nor NVMe.

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#26

Post by Freaky » Fri, Mar 04, 2016, 2:10 AM UTC

cm2187 wrote: post #6

NovaS1X wrote: post #2

Impressive. First question that pops into mind is how long the rebuild time would take if one of these failed in a RAID. I can imagine it'll take a while.

I thought RAID and SSD were a terrible combination. As if both drives do exactly the same writes at the same time, chances are they will fail at the same time. Plus most RAID controllers don't support TRIM. Has the thinking changed?

> As if both drives do exactly the same writes at the same time, chances are they will fail at the same time.

You mean due to exhausting their endurance? This is something you monitor, you should have plenty of time to replace the drives before it becomes a concern.

For other failures, how's it going to be any different from normal HD's? There's always the risk that having the same models/batches in the same conditions might lead to a cluster of failures, but RAID's still likely to save you from plenty of other failure modes.

For instance, the recent Google study[1] suggests that uncorrectable errors with SSDs are actually more common than HD's: "More than 20% of flash drives develop uncorrectable errors in a four year period... significantly higher rates .. than hard disk drives".

I've certainly seen enough IO errors from SSDs to know I want to defend against them. Not to mention the silent data corruption I've seen (and been protected from, yay ZFS).

1: http://0b4af6cdc2f0c5998459-c0245c5c937c5dedcca3f1764ecc9b2f...

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#27

Post by hendry » Fri, Mar 04, 2016, 2:11 AM UTC

On Amazon UK, the highest capacity Samsung SSD I can find is 2TB for 620GBP. So I am wondering when this 15TB we actually hit stores and what's the sweet spot price wise between 1 & 15TB.

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#28

Post by [deleted] » Fri, Mar 04, 2016, 2:13 AM UTC

[deleted]

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#29

Post by imaginenore » Fri, Mar 04, 2016, 2:16 AM UTC

jschwartzi wrote: post #18

imaginenore wrote: post #12

Earlier quoted context omitted.

It's still less dense than 200GB MicroSD cards. (which are only $79.50 on Amazon)

Does that density include the connectors and buses that would be required to access those cards?

Then you have to include the connectors and buses to access the SSD as well.

And it will still be in favor of microsd, which can be read by a tiny connector + tiny controller in a smartphone.

Re: Samsung ships the world's highest capacity SSD, with 15TB of storage

#30

Post by bluedino » Fri, Mar 04, 2016, 2:20 AM UTC

hendry wrote: post #27

On Amazon UK, the highest capacity Samsung SSD I can find is 2TB for 620GBP. So I am wondering when this 15TB we actually hit stores and what's the sweet spot price wise between 1 & 15TB.

It's a SAS device which isn't meant for retail sales and probably only available to select enterprise customers and OEMs