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Comment Re:Intel is blowing (Score 1) 80

And, of course, any Linux or BSD operating system will use all available memory for cache data from storage anyway. I guess Windows needs a little more help to do that.

This certainly shows up in, for example, Chrome startup times. It takes around 4 seconds from a hard drive, uncached, 1 second from a SSD, 1 second from a NVMe drive, and presumably 1 second from any other form of storage because chrome itself needs a bit of cpu time to initialize itself, not to mention the time it takes to load a tab (minimum 0.5 seconds).

So honestly once one transitions from the HDD to a SATA SSD, where the difference is noticeable, any further transitions (SATA SSD -> NAND NVME SSD -> XPOINT NVME SSD -> XPOINT DDRs) are not likely to be noticeable, even without a ram cache.

I think Intel's ENTIRE marketing effort revolves around Windows' slow startup times. Or more to the point, Windows tends to seek the storage device a lot while starting up which is *very* noticeable if you have a hard drive, but most irrelevant if you have any sort of SSD.

Since one can accomplish the same thing simply buy purchasing a small SSD, I just don't see them being able to make a case for it being 'easier' as a disk caching substitute verses someone coming to the realization that their time and data are valuable enough to actually spend a bit more money on buying some native SSD storage in the first place.

The advent of the cloud is also making local mass storage less and less relevant. Here I'm not talking about those of us who insist on having our own local archives (mine is getting close to 4TB now, with another 4TB in two backup locations so... that's 12TB of storage for me). I'm talking about 'normal' people who are using cloud storage more and more often. They won't need Intel's ridiculous 'solution' either (not even mentioning the fact that a normal NAND NVME SSD to cache a HDD is a better fix for the solution they are marketing than their Optane junk).

-Matt

Comment Re:Being confused... (Score 1) 80

Motherboard vendors are just now, finally, starting to put M.2 connectors on the motherboard. Blame Intel for the slow rate of adoption. Intel came out with three different formats, all basically incompatible with each other, and created mass confusion.

But now, finally, mobo vendors are settling on a single PCIe-only M.2 format. Thank god. They are finally starting to put one or more M.2 slots and finally starting to put on U.2 connectors for larger NVMe SSDs. Having fewer SATA ports on the mobo is no longer a marketing issue. I've seen many more mobos recently with just 2-4 SATA ports.

-Matt

Comment Re:Thanks for the ad, I guess, but you missed some (Score 1) 80

It would depend on the relative latency and other characteristics. XPoint is definitely not it, because XPoint can't handle unlimited writing. But in some future lets say we do have a non-volatile storage mechanic that has effectively unlimited durability, like ram, but which is significantly more dense, like XPoint.

In that situation I can see systems supporting a chunk of that sort of storage as if it were memory.

Latency matters greatly here for several reasons. First, I don't think XPoint is quite fast enough, at least not yet. The problem with any sort of high-latency storage being treated like memory at the HARDWARE level is because that latency creates massive stalls on the cpu. DRAM today causes huge many-clock stalls on a cpu. These stalls are transparent to the operating system, so the operating system cannot just switch to another thread or do other work during the stall. The stall effectively reduces the performance of the system. This is the #1 problem with treating any sort of storage technology as if it were memory.

The #2 problem is that memory is far easier to corrupt than storage (which requires a block transaction to write). I would never want to map my filesystem entire storage's block device directly into memory, for example. It's just too dangerous.

The solution that exists today is, of course, swap space. You simply configure your swap on an SSD. The latencies are obviously much higher than they would be for a HW XPoint style solution, around 50-100uS to take a page-fault requiring I/O from a NVMe SSD, for example.

The difference though is that the operating system knows that it is taking the page-fault and can switch to another runnable thread in the mean time, so the CPU is not stalled for 50-100uS. It's doing other work. Given enough pending work, the practical overhead of a page-fault in terms of lost CPU time is only around 2-4uS.

In a XPoint-like all-hardware solution, the CPU will stall on the miss. If the XPoint 'pagein' time is 1-2uS, then the all-hardware solution winds up only being twice as good as the swap space solution in terms of CPU cycles. Of course, the all-hardware solution will be far better in terms of latency (1-2uS verses 50-100uS).

But to really work in this format the non-volatile memory needs to have a nearly unlimited write capability. XPoint does not. XPoint only has around 33,000 write cycles of durability per cell (and that's being generous). It needs to be half a million at a minimum and at least 10 million to *really* be useful.

-Matt

Comment Re:Intel is blowing (Score 1) 80

Intel devices have quirks, but I think you are mixing apples and oranges here. All modern filesystems systems have used larger alignments for ages. The only real issue was that the original *DOS* partition table offset the base of the slice the main filesystem was put on by a weird multiple of 512 bytes which was not even 4K aligned.

This has not been an issue for years. It was fixed long ago on DOS systems and does not exist at all on EFI systems. Regardless of the operating system.

At the same time, all SSDs past the second generation became sophisticated enough that they really stopped caring about alignment for most practical use cases.

Where Intel does mess up depends on the device. In the 600P's case, the firmware is poorly designed in many respects. In other cases, such as with the 750, performance implodes with large block sizes (64KB or higher). This just makes the device less worthy, because frankly NO OTHER SSD VENDOR has these sorts of idiotic problems.

All of that said, insofar as operating systems go, these storage-level devices have no real visibility into, understanding of, or optimizations for one particular filesystem verses another. So for all practical situations, there is NO raw performance difference between Windows, MacOS, Linux, or any of the BSD's for these storage level devices. They are completely OS-agnostic and have always been completely OS-agnostic.

-Matt

Comment Re:Intel is blowing (Score 2) 80

Right. They are trying to market it as something cool and new, which would be great except for the fact that it isn't cool OR new. A person can already use ANY storage device to accelerate any OTHER storage device. There are dozens of 'drive accelerators' on the market and have been for years. So if a person really wanted to, they could trivially use a small NAND flash based NVMe SSD to do the same thing, and get better results because they'll have a lot more flash. A person could even use a normal SATA SSD for the same purpose.

What Intel is not telling people is that NOBODY WILL NOTICE the lower latency of their XPoint product. At (I am assuming for this product) 10uS the Intel XPoint NVMe is roughly 1/6 the latency of a Samsung NVMe device. Nobody is going to notice the difference between 10uS and 60uS. Even most *server* workloads wouldn't care. But I guarantee that people WILL notice the fact that the Intel device is caching much less data than they could be caching for the same money with a NAND-based NVMe SSD or even just a SATA SSD.

In otherwords, Intel's product is worthless.

-Matt

Comment Intel is blowing (Score 3, Insightful) 80

Smoke. Total and complete nonsense. Why would I want to buy their over-priced octane junk verses a Samsung 951* or 960* NVMe drive? Far more storage for around $115-$130, 1.4 GBytes/sec consistent read performance, decent write performance, and decent durability.

P.S. the Intel 600P NVMe drive is also horrid, don't buy it.

http://apollo.backplane.com/DF...

-Matt

Comment Its rather exaggerated (Score 5, Interesting) 63

Intels claims are rather exaggerated. Their claims have already been torn apart on numerous tech forums. At best we're talking only a ~3-5x reduction in QD1 latency and the intentionally omit vital information in the specs to force everyone to guess what the actual durability of the XPoint devices is. They say '12PB' of durability for the 375GB part but refuse to tell us how much overprovisioning they do. They say '30 drive writes per day' without tellling us what the warrenty will be.

In fact, over the last 6 months Intel has walked back their claims by orders of magnitude, to the point now where they don't even claim to be bandwidth competitive. They focus on low queue depths and and play fast and loose with the stats they supply.

For example, their QOS guarantee is only 60uS 4KB (99.999%) random access latency and in the same breath they talk about being orders of magnitude faster than NAND NVMe devices. They fail to mention that, for example, the Samsung NVMe devices also typically run around ~60-70uS QD1 latencies. Then Intel mumbles about 10uS latencies but bandies about large factors of improvement over NAND NVMe devices, far larger than the 6:1 one gets simply assuming 10uS vs 60uS.

Then they go on to say that they will have a NVDIMM form for the device later this year, with much faster access times (since in the NVMe form factor access times are constricted by the PCIe bus and block I/O protocol). But with potentially only 33,000 rewrite cycles per cell to failure that's seriously problematic. (And that's the best guess, since Intel won't actually tell us what the cell durability is).

--

The price point is way too high for what XPoint in the NVMe format appears to actually be capable of doing. The metrics look impossible for a NVDIMM form later this year. Literally we are supposed to actually buy the thing to get actual performance metrics for it? I don't think so.

Its insane. This is probably the biggest marketing failure Intel has ever had. Don't they realize that nobody is being fooled by their crap specs?

-Matt

Comment Another nail in the coffin for Firefox (Score 1) 322

Pulseaudio is nortiously linux-specific. We've had nothing but trouble trying to use it on BSD and switched to ALSA (which is a lot more reliable on BSDs) a year or two ago for that reason.

I guess that's the end of Firefox's portability. Most of our users use Chromium anyway because Firefox has been so unstable and crash-prone. Long live Chromium?

-Matt

Comment Re:I'll stick with HDDs for now (Score 1) 167

Your problem was that you were using Kingston, Patriot, etc... all third-rate SSD vendors who use whatever flash chips happen to be cheapest. Crucial (aka Micron), Samsung, and a few others are first-line vendors.

SSDs can certainly fail, but its kinda like PSUs... some vendors are first-line, most are not.

-Matt

Comment Now this is very cool (Score 5, Insightful) 306

Or Hot :-). I read a number of articles from analysts who thought it would take around 15 years for the technology to be produced in commercial volumes. But the fact that it looks like this is going to happen at all, even with a 10-15 year time-frame, is a BIG deal. 3x the charge will give electric vehicles a 600+ mile range.

-Matt

Comment What, you haven't noticed until now? (Score 1) 644

Ultimately automation improves everyone's quality of life, but it does so by requiring fewer workers for the same output. The work available is higher-quality (improved quality of life), but there are fewer slots. Automation also reduces the cost of goods. Just google the relative cost (out of your salary... the percentage of your work time required to fund it) for, say, heating and lighting your home for example and compare with the cost a hundred years ago. Conditions are so much better today than, say, in the 1800's, or 1700's, or 1600's.

But there is a cost. Automation and technology also cause a major dislocation as the population must find new and different things to do than the things they did before.

Look at coal mining today. Since the 50's, output has gone from roughly 1:1 (ton:worker) to 12:1 (ton:worker). In other words, your average coal mine today has 1/12 the number of workers needed for the same output 70 years ago. The same thing is happening in ALL industries.

However, automation also creates relatively severe economic disparities between people. Investors get a larger piece of the pie, workers get a smaller piece of the pie. This is because automation improves margins (even when goods cost less) but the larger number of people trying to go after fewer job slots forces wages down. Since investors tend to be more affluent, the result is that the rich get much richer and the poor get much poorer, relatively speaking. Even including the fact that there must be people to buy the goods in order to be able to sell them, the goods do not become cheaper quickly enough to completely offset the difference in economic standing.

Most people don't understand that this is a relative equation, not an absolute equation. The quality of life for everyone can improve at the same time that the economic disparity increases. But perception is relative in nature, and today's society is not kind to people doing dumb things (credit card debt being a prime example).

A *LARGE* portion of US citizens do dumb things, not the least of which being to elect people to government by relying on promises that translate, in reality, to the exact opposite of what the person was elected to achieve. Take taxes for example. Remember that the Rich already have most of the wealth in the U.S. All current policy now points to a major reduction of taxes on the Rich. A number of states have tried to reduce taxes. That is going to make the gap even worse. Your typical tax payer on the lower-end of the economic scale might save $200 in a year. Your typical affluent 'rich' person is going to save $200,000 in a year. And more. And yet people vote for this crap because they think saving that $200 will make life better. It won't, because the whole system will then rebalance based on $200,200 which puts the people on the lower-end of the economic scale in an even worse position a few years down the line. Its like spreading a few crumbs onto the pavement while the master eats 99.9% of the pie.

-Matt

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