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Comment Re:Fairly low endurance numbers (Score 1) 108

I'm not sure why you are assuming that the SSDs are only being used for general purpose loads. I would expect most enterprise SSD installations will be specifically tailored to the application they are supporting.

That is certainly the case for someone like Facebook or Apple, for example. One is basically write-once/read-many (The facebook platform itself), the other is write-once/distribute-many (Apple's content distribution network). And any batch big-data processing related to those services will be an entirely different subsystem, with its own SSD tailoring.

If a large SSD is used for caching, that's yet a different tailoring. Front-end caching is not necessarily write-intensive, though it can be. It would depend on the application and the size of the cache. In these cases it really just comes down to how much data is written to the array each day vs desired durability of the SSDs.

-Matt

Comment Re:Fairly low endurance numbers (Score 1) 108

The numbers are right. It is also likely that those cards can handle far more writes, just not under warranty.

You have to be a bit careful about the petabyte capability tests. The flash cells in those tests might appear to work for the test but are probably sufficiently worn such that their unpowered data retention is at sub-par levels (like a few weeks instead of a year).

Generally speaking you do want to replace the unit when the wear level indicator gets close to zero.

-Matt

Comment Re:Fairly low endurance numbers (Score 1) 108

Enterprise SSDs usually come in two forms: (1) Read-intensive (lower cost, lower write durability) and (2) Write-intensive (higher cost, higher write durability). The only real difference between the two is that the write-intensive form implements a lot more over-provisioning (60% to 100%), and secondarily might use higher-quality bin-selected flash chips.

-Matt

Comment Re:This is nice, but... (Score 1) 108

Please note that the Acer C720's M.2 slot is really an mSATA slot. It is not a NGFF slot (it is the older two-slot form factor that farms out SATA, not PCIe). You probably cannot stuff a NVMe card into it.

On these small PCs the mobos often have slots for WIFI cards, which are another form factor entirely and also not NVMe compatible.

-Matt

Comment Starting to see more motherboards with M.2/NGFF (Score 3, Insightful) 108

It's nice to finally start seeing more motherboards with M.2/NGFF slots on the motherboard. So far most of the offerings have only one slot, and still sport way more SATA connectors than anyone needs. But I expect the offerings to get better through 2017.

Another thing to note is that there is a new 2.5" drive form factor... same dimensions as a 2.5" SATA drive, but with a different connector, which allows more substantial 2.5" form factor SSDs to use NVMe. There is also a new on-motherboard connector standard for the new 2.5" drive interfacing that makes use of a blocky SAS connector (but is not SAS... is PCIe for NVMe interconnect), and there are motherboards available now with one of these on them. And, again, in 2017 I fully expect motherboards to start coming out with more of these connectors.

In the mean time you can get standard PCIe cards that farm-out the correct connector for what you need (either the NGFF connector or the SAS connector). Please note that BIOSes for motherboards without native connectors probably do NOT support booting from NVMe, and if they do it will be UEFI booting only (no legacy booting from NVMe).

Just by way of information: M.2/NGFF is basically just a PCIe bus in a different format. It's a compact 4-lane PCIe bus format. However, there are *FOUR* different connector styles for M.2-style connectors, called by various names (M.2, NGFF, mSATA, mWIFI, and other crap). Be very careful to buy stuff that matches up. You want the NGFF connector (also known as M.2, but NGFF is the modern term for it and will be less confusing). This connector has one notch to one side and one hold-down screw at the end of the board along the center-line.

Another thing to be careful of is that a bunch of vendors have NGFF boards that are *NOT* NVMe. The boards actually have a SATA controller on-board and will attach via AHCI. Examples include Kingston HyperX and Plextor. All the Samsung products are NVMe.

For low-cost NVMe, another alternative to the 950 Pro is the somewhat older Samsung NVME SM951.

Most of these NGFF NVMe boards are capable of doing 3 GBytes/sec reading (deep queue). Writing will be a lot slower, even slower than a typical SATA SSD due to having fewer flash chips. Also, 3 GBytes/sec is if you plug it into a PCIe-v3 slot. Most machines out there today will have PCIe-v2 slots and performance will be more in the 1.5 GBytes/sec range. It is still fast as hell reading.

-Matt

Comment Probably accidentally ingested (Score 1) 182

Of course we don't for sure, but if he was taking apart that stuff with his bare hands he was probably accidentally ingesting small amounts of contaminated material from whatever got onto his hands and dust getting onto food, the air he was breathing, etc. Remember, he was taking apart hundreds to possibly thousands of devices.

Ingestion is what killed the ladies painting aircraft instrument dials with radium-laced paint (the radium to make the dials glow in the dark). In that case it was more direct, the ladies often licked the small paintburshes they used to sharpen the point.

It is really unlikely that he would have been poisoned just by nominal free-air radiation from the stuff in his lab. In fact, I wouldn't be surprised if he had Geiger counters lying around and thought that taking readings would render sufficient safety.

-Matt

Comment Re:SD cards are only for digital cameras? (Score 1) 675

Transfering RAWs wirelessly isn't a problem from a bandwidth standpoint. However, to work well the uplink has to be asynchronous, concurrent with normal camera operation, and not interfere with camera operation if no wifi connection is available.

Unfortunately, no current camera or wireless interface can actually do that seemlessly. The closest I've seen is actually a 10-year-old wifi grip from Canon which could transfer asynchronously via FTP whenever it was able to get a connection. I used it extensively. But (for example), all of Canon's Wifi offerings since then have been unusable crap.

Unfortunately, most modern camera wifi setups are complete crap, even ones that are camera-independent. They usually connect only through manufacturer servers, require a dedicated app, usually can't operate concurrent with normal camera operation, and/or will glitch/stall the camera if they can't get a good wifi connection.

Independent products such as EyeFi are getting better, but still very poorly implemented. There isn't a single camera vendor or independent product that works well, currently.

-Matt

Comment Re:He misses the point (Score 1) 675

Well, you can try using a SD card for general storage. Good luck with the extremely poor random write performance and lack of redundancy most of those cards are going to have. They are designed for cameras and cell phones and will generally die very quickly if you write-cycle them as much as you would a normal filesystem. The SD card hardware isn't even queued. For that matter the USB memory sticks aren't that much better. They are better... just not much better.

My preference for external storage is to actually carry along a 2.5" SATA SSD and a SATA->USB adapter. Very high performance reading and writing, both random and sequential, and I can just stuff the SSD into a hot-swap slot on my workstation when I get home.

-Matt

Comment Well, he's right to a degree (Score 2) 675

There are two major SD card form factors, three if you include compact flash. There are two major USB connectors for computers (USB and USB-C, not including two the two micro-usb form factors or the large square 'device' connectors). There are *five* video form factors, four of which are still current (DVI, HDMI, DP, Mini-DP).

So he has a point. However, the new macbook-pro goes too far in removing ports. Standard USB ports are still *extremely* useful and for a laptop having a bunch of them is also extremely useful. They removed the separate power port, which basically means there is only one USB-C port available for peripherals.

To say it is stupid is not being critical enough.

-Matt

Comment No pricing? What about durability? (Score 2) 280

There's no point if its too expensive, or if the durability is 25 years (which destroys the whole payback equation). This is kinda like the power-wall. Great concept, but the technology isn't quite there yet. And it may not be quite there for solar roofing tiles either.

Speaking of which, several companies tried selling solar roofing tiles in the past, and had to give up on lack of sales. It isn't a new technology. The question is... is it good enough to hit the necessary sweet spot? My guess... probably not yet.

-Matt

Comment Silly spec comparison, and System76 (Score 2) 535

I have a System76, but honestly I barely use it because it is loud and it has the worst laptop keyboard I've ever encountered (the key spacing is designed for people with HUUUGE hands and any lateral force causes the key to stick and not go down, making typing nearly impossible). And the battery life aint too hot either. The System76 is powerful, but inconvenient. I actually prefer my chromebook, which is much smaller (smaller screen, lower resolution, much less ram, much slower cpu, etc)... but far more usable.

Apple stuff is expensive, but I wonder about people who complain about base specs all the time. 'more' is not necessarily 'better'. My dinky little chromebook has only 4G of ram but I don't even feel it when it pages to/from its SSD. There's no point stuffing 32GB of ram into a laptop, frankly. It's just a waste of power (and money).

I will of course stuff as much ram into a box as is economically feasible, just because I'm me. I have a dual-socket xeon system with 128GB of ram, for example, and I have a broadwell desktop with 64GB of ram. Both are being used as servers and build boxes at the moment.

But the box I currently use for my workstation only has 8GB of ram and I don't feel the paging to/from the SSD even with tons of Chrome windows leaking memory all over the place so I have been in no hurry to replace. In fact, my workstation is just a dinky old Haswell i3 box, and yet it has no problem driving two 4K monitors or playing video. It wouldn't win any prizes playing games, but then again I don't use it to play games.

Update to present-day NVMe SSDs, which have ~3-5x the read performance of a SATA SSD, and I kinda wonder where these complaints come from.

-Matt

Comment Stupid article (Score 1) 79

Satellite pagers (and in more modern times, texts over the cellular network) are the most reliable way to get alarms out to field and on-call personal. Sure, someone could send a malicious fake page or text, but these alarms are mainly just heads-up to personal who are not in the operations center that something is amis. The main board will always be checked / personal will always call in and double check before anyone actually pushes any buttons.

This is a really stupid article.

-Matt

Comment Re:First lesson (Score 4, Interesting) 135

I have two major beefs with IPV6. The first is that the end-point 2^48 switch address space wasn't well thought-through. Hey, wouldn't it be great if we didn't have to use NAT and give all of those IOT devices their own IPV6 address? Well... no actually, NAT does a pretty good job of obscuring the internal topology of the end-point network. Just having a statefull firewall and no NAT exposes the internal topology. Not such a good idea.

The second is that all the discovery protocols were left unencrypted and made complex enough to virtually guarantee a plethora of possible exploits. Some have been discovered and fixed, I guarantee there are many more in the wings. IPV4 security is a well known problem with well known solutions. IPV6 security is a different beast entirely.

Other problems including the excessively flexible protocol layering allowing for all sorts of encapsulation tricks (some of which have already been demonstrated), pasting on a 'mandatory' IPSEC without integration with a mandatory secure validation framework (making it worthless w/regards to generic applications being able to assert a packet-level secure connection), assumptions that the address space would be too big to scan (yah right... the hackers didn't get that memo my tcpdump tells me), not making use of MAC-layer features that would have improved local LAN security, if only a little. Also idiotically and arbitrarily blocking off a switch subspace, eating 48 bits for no good reason and trying to disallow routing within that space (which will soon have to be changed considering that number of people who want to have stateful *routers* to break up their sub-48-bit traffic and who have no desire whatsoever to treat those 48 bits as one big switched sub-space).

The list goes on. But now we are saddled with this pile, so we have to deal with it.

-Matt

Comment Flood defenses? (Score 5, Informative) 135

There is no flood defense possible for most businesses at the tail-end of the pipe. When an attacker pushes a terrabit/s at you and at all the routers in the path leading to you as well as other leafs that terminate at those routers, from 3 million different IP addresses from compromised IOT devices, your internet pipes are dead, no matter how much redundancy you have.

Only the biggest companies out there can handle these kinds of attacks. The backbone providers have some defenses, but it isn't as simple as just blocking a few IPs.

-Matt

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