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The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

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Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#51

Post by endorphone »

Dylan16807 wrote: post #46
endorphone wrote: post #43

Earlier quoted context omitted.

3D XPoint has extremely low latency (e.g. 7 usec), and has already been demonstrated as such. Putting it through a PCI slot and a storage controller is not the same. The discussion is about running it as DIMM memory through a normal memory controller.

So you remove the storage controller and PCIe bus and you go from 10us to 7us. 7us is still a hundred times slower than DRAM, is it not?

It's about 30 times slower than the real-world latency of RAM, which is obviously a problem but it's one that caching might resolve (e.g. an L4 of 32GB of GDDR5)

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#52

Post by Dylan16807 »

_wmd wrote: post #49
Dylan16807 wrote: post #46

Earlier quoted context omitted.

So you remove the storage controller and PCIe bus and you go from 10us to 7us. 7us is still a hundred times slower than DRAM, is it not?

You're ignoring a lot of context being created by the parent comment. While the latencies may never directly compete with DRAM, planned densities are already more than favourable. Having a 2TB chunk of persistent memory mapped into your address space with single-thread performance exceeding 100,000 random reads/sec with extremely consistent latency is a game-changer in for example database applications.

What context am I missing? While Analemma_ was talking about using it to augment DRAM, like you are, endorphone was very specifically talking about replacing DRAM in that comment. And that comment claims that it already has good enough latency for the job.

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#53

Post by endorphone »

Dylan16807 wrote: post #52
_wmd wrote: post #49

Earlier quoted context omitted.

You're ignoring a lot of context being created by the parent comment. While the latencies may never directly compete with DRAM, planned densities are already more than favourable. Having a 2TB chunk of persistent memory mapped into your address space with single-thread performance exceeding 100,000 random reads/sec with extremely consistent latency is a game-changer in for example database applications.

What context am I missing? While Analemma_ was talking about using it to augment DRAM, like you are, endorphone was very specifically talking about replacing DRAM in that comment. And that comment claims that it already has good enough latency for the job.

It's turtles all the way down, and I think this is needlessly splitting hairs.

L1->L2->L3->(L4->)DRAM->Storage

3D XPoint is being considered as the DIMM-module, byte-addressed "memory" before storage. Saying that it "augments" DRAM is almost meaningless because we already have multiple levels of DRAM.

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#54

Post by mozumder »

elorant wrote: post #34

Which are the use cases for an SSD like that? Would I see improvements if I were to load my db on it or is it for working with bigger files?

These are going to be absolute beasts for databases.

Databases are best on drives that have reduced latencies. Data access is random and keeps jumping around the drive for joins. Your SELECT statements are going to speed up in proportion to latency improvements.

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#55

Post by benlwalker »

I'm the technical lead for the Storage Performance Development Kit (http://spdk.io). I have one of these in my development system and we're hoping to post benchmarks fairly soon. SPDK further reduces the latency at QD 1 by several microseconds. It's an impressive device!

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#56

Post by elorant »

chx wrote: post #35
bkeroack wrote: post #33

Earlier quoted context omitted.

With public cloud, you're paying for the control plane. Period. Yes the raw compute cost is much higher (and the performance often less) than bare metal, but software development is really, really expensive. With the public cloud you get the result of literally millions of programmer-hours "for free". To many that's worth it (at least at first, below a certain scale). This is also one reason why Kubernetes is really…

I really badly do not understand what EC2 gives you that a dedicated box doesn't. Yes, if you use all the other services, then there's a value but then again for example SQS is a particularly shitty queue.

It gives you dev ops out of the box. For small projects it has its merits. For most developers tinkering with the server isn't high in their priority list. I'm with you on dedicated but if I were to run an asynchronous crawler I'd rather go with AWS and save me the trouble of setting up the proper environment.

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#57

Post by boznz »

bbulkow wrote: post #21
mtanski wrote: post #6

Some people like to claim that old storage technologies go away. But in reality old storage technologies live on along side of new... all that happens is that we end up having more tiers to deal with. Drum magnetic memory has been replace but we still have spinning rust, tape, optical, DRAM, SRAM, SSD...

There are only 3 forms of bit storage, historically. 1) Poking holes in things ( tape, DVD, etc ) 2) Magnets ( core memory, drum memory, tape, disks ) 3) Circuits ( DRAM, NAND, etc ) Examples of all three of these still exist. What's interesting about XPoint is it is literally a fourth form that has never been commercially available: melting a substance and cooling it quickly or slowly, forming either a crystal or am…

Memristors would technically be another form of storage but after the hype HP have been a bit quiet on this for the last 3 years.

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#58

Post by davrosthedalek »

endorphone wrote: post #53
Dylan16807 wrote: post #52

Earlier quoted context omitted.

What context am I missing? While Analemma_ was talking about using it to augment DRAM, like you are, endorphone was very specifically talking about replacing DRAM in that comment. And that comment claims that it already has good enough latency for the job.

It's turtles all the way down, and I think this is needlessly splitting hairs. L1->L2->L3->(L4->)DRAM->Storage 3D XPoint is being considered as the DIMM-module, byte-addressed "memory" before storage. Saying that it "augments" DRAM is almost meaningless because we already have multiple levels of DRAM.

If I am not mistaken, we have only one level of DRAM. Caches are SRAM. (Also, DRAM on DIMM is not byte-addressable)

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#59

Post by mozumder »

saosebastiao wrote: post #5

Impressive. On a semi-related note, the fact that cloud providers offer managed Postgres databases is great, but things like this keep pushing me to think about bare metal in colo. A $20,000 server/backup combo with a couple of these will give me 5x the performance of a server that costs me $70k/year on AWS before provisioned IOPS . That's a huge gap to play with for taking care of your own maintenance costs.

You don't even need to co-lo. Just build a system for your home on a static IP address with a business account from your ISP.

It's so much cheaper than AWS, and you get unlimited bandwidth.

Re: The Intel Optane SSD DC P4800X (375GB) Review: Testing 3D XPoint Performance

#60

Post by agumonkey »

blacksmith_tb wrote: post #31
agumonkey wrote: post #26

Earlier quoted context omitted.

Optical discs are relegated to back shelves too. Hard to beat cheap rewritable nand flash. ps: I'd be curious about a tiny, 2017 laptop friendly optical disc storage. Say a 2.5" RW BD layer in cartridge. A modern mini disc.

I doubt anything could be compact enough to be laptop friendly in the sense of being a physical part of the machine - but external USB 3 BD burners are quite small (powered over usb, too), I have a Samsung which works fine.

i don't know, a small radius "may" help remove mecanical constraints, and with a non stacked lens design sdcard reader height device.

I was mostly wonder about the psychological aspect of form factor. naked optical disks are non-personal, mini discs weren't. You interacted with them freely, carried them as is in your pocket. A large enough yet tiny enough reincarnation might be "fun".

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