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

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

#71

Post by Dylan16807 »

uxcn wrote: post #63
Dylan16807 wrote: post #59

Earlier quoted context omitted.

It's a pretty bad database that can't queue up enough reads to keep the drive constantly active during a full-table scan.

It's a throughput problem, not an activity problem. Normally, since the rows are a fixed size the dbms will lay them out sequentially on disk. So, when the database reads from disk unless you read every column in the row, the dbms has to skip over data. This is kind of a high level picture, but hopefully it illustrates the point. Nearly all of the tick (>4GB/day) databases I've used aren't laid row oriented.

It doesn't have to skip over data if that would slow it down. I would expect your typical database to have some kind of index or bitmap that can tell it what to grab fast enough to saturate the disk while avoiding unused data, but if it has to fall back to vacuuming up 1GB at a time then so be it.

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

#72

Post by [deleted] »

sdesol wrote: post #11
cm2187 wrote: post #6

Earlier quoted context omitted.

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?

> I thought RAID and SSD were a terrible combination Well there are different RAID settings. My product is an indexing engine (indexes Git repositories) and I've personally found RAID 0 reduces indexing time by about 30% compared to a single drive. I have a machine that has 4 SSDs running RAID 0 and I've found the performance gain after 3 SSDs is negligible. It seems like 3 SSDs running RAID 0 is the best combination…

[deleted]

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

#73

Post by adrianN »

dahart wrote: post #68
dorfsmay wrote: post #54

Earlier quoted context omitted.

Our brain thinks linear, technology grows exponentially. http://www.kurzweilai.net/the-law-of-accelerating-returns

Kurzweil also claims, as the capstone final paragraph in this piece, that human life expectancy is on an exponential curve, which is false. Not just a little wrong, it's all the way wrong, and intentionally misleading, there's no possible way he doesn't know it's false. It's very easy to check the basic facts: https://en.m.wikipedia.org/wiki/Life_expectancy . Lifespan for people who live past 20 (discounting infant m…

I agree that the claim that lifespan is on an exponential curve is bogus. Modern medicine basically extended extremal lifespan up to the maximum attainable without fixing the underlying causes of aging and then stopped. There is for example some research that shows that the oldest woman's blood was derived from just two stem cells.[1] We currently don't have the technology to fix problems like that

I disagree however that nobody alive today will live "forever". The technology that might allow us to fix aging is on an exponential curve, look for example at the cost of genome sequencing. So the time is ripe for some breakthrough results in aging research that actually address some causes of aging.

[1] https://www.newscientist.com/article/dn25458-blood-of-worlds...

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

#74

Post by ryao »

guy_c wrote: post #19
stray wrote: post #16

Earlier quoted context omitted.

That sounds perfectly reasonable, and 20 years ago I'd have said the same thing. It's even fairly likely that I did say it. You know where this is going, right? I was a SysAdmin at the time and one of the things I was responsible for was Oracle Financials. It was at the core of everything that mattered at that company -- and I was absolutely convinced that short of a water balloon fight in the machine room, my raid c…

I wonder, for such mission critical data a good strategy would be to start rotating out old drives at set periods. Maybe replace one drive of your RAID5 every 6 months, not matter what the health. Once you've replaced all the drives, they will all be staggered in age by 6 months. Hopefully then the chances of multiple failures is greatly reduced.

For mission critical data, you should have backups and use at least triple mirrors or raidz2. Quadruple mirrors or raidz3 are even better for the extra paranoid.

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

#75

Post by SixSigma »

hyperpallium wrote: post #41
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…

They're not guaranteeing failure in 5 years, but are pretty sure it won't fail. If "pretty sure" is 98%, then that's 100K (or something like it, probability maths is hard).

Thet aren't guaranteeing anything. They are saying they will replace it if it fails inside 5 years.

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

#76

Post by cm2187 »

chipperyman573 wrote: post #8
cm2187 wrote: post #6

Earlier quoted context omitted.

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?

Yeah, the statistical chance of the same thing happening on both drives is the same, but the chance of it happening at the same time is pretty low.

That might have been the case with HDD, and the rationale of using RAID. But I thought that with SSD, if you have drives in RAID 1 or RAID 5, each drive makes the same amount of writes at the same time, and if they are the same model / age, the firmware will allocate the writes to the same cell. And you would end up with exactly the same wear on all cells. And therefore all drives failing simultaneously.

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

#77

Post by DanBC »

chime wrote: post #55
_wmd wrote: post #50

Earlier quoted context omitted.

You're asking for 2 major tech steppings in a single product. We don't even have many mass market NVMe drives yet, and that aside, they're undoubtedly pushing the limits of their existing controller tech just to handle the capacity. Has NVMe seen much enterprise adoption yet? No surprise they chose an interface to match their intended customers' existing product lines

We put a couple of Intel 750s in our primary DB server and so many of our issues just went away instantly. Reading at 2GB/s is amazing. On a 10gb network, our network backups now happen at 1+GB/s. Of course we optimize our DB queries as much as possible but sometimes, you just hit a brick wall and can't speed things up because of how the data is structured. Instead of spending 100 developer/dbadmin hours on reorganiz…

A blog post with some details and graphs would be appreciated by the HN readership.

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

#78

Post by medecau »

deelowe wrote: post #61
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…

Given how SSDs work, this is actually pretty good reliability. No one is going to be writing the full disk of 15 TB of data every day.

This disk looks just right for fatcache usage.

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

#79

Post by cm2187 »

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.

Samsung is expected to release a 4TB consumer SSD this summer. Might be a better bargain that this enterprise SSD.

http://www.anandtech.com/show/9652/samsung-details-3rd-gen-v...

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

#80

Post by vlasev »

thecatspaw wrote: post #69
fakename wrote: post #66

and a 2015 macbook pro still ships with 128gb

Not sure what you're talking about, mine shipped with 1tb, my work has some with 500gb and 1tb as well.

The maximum on the Apple site is 512GB standard but you can purchase 1TB to make it 500 dollars extra.
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