Where are they implying this? Just because something fits into a DIMM socket doesn't imply that it's equivalent to DRAM, that would be an unfounded assumption.
In all of the Optane marketing material that I have seen they mention that Optane fits a performance niche in between DRAM and NAND. That it is less-than-DRAM in the performance aspect, and more-than-DRAM in the capacity and non-volatile aspects.
I had written a fairly large comment defending Intel, then realized that I was almost positive there isn't any tag ram to use that DRAM like a cache. 3dxpt really *should* be the memory on these servers, but it looks like the only way to switch between them is either some sort of manual partition (which will probably work fine in practice with huge databases) or the same trick currently used in consumer trash with 3dxpt labled as "memory": simply use the 3dxpt as storage with a large virtual drive hanging off of it.
Talk about baby steps, can they make this thing even more of a niche item?
Presumably the people purchasing a system with Optane sitting in DIMM slots would understand what they're buying and align the equipment to a role that properly leverages the hardware. This isn't like an end user picking up a Chromebook at WalMart that's surprised that it doesn't run Windows after unboxing it at home. I think to make the argument you're making ignores the target buyer knowledge base in order to justify what is otherwise unreasonable outrage over a new piece of technology that you strangely feel is some sort of threat to you.
RAM has always been measured in GiB/TiB, so whenever someone says GB it's safe to assume they mean GiB. Opposite for network bandwidth. It's those evil optical and magnetic storage companies that decided to confuse everyone.
I have a bad feeling about Optane. Something tells me that Xpoint will be sold as actual DRAM for entry level VMs on Azure, AWS and other cloud services.
You do know that anyone could write an AVX job to run on a VM and if run on the same CPU as your VM would reduce your memory latency and bandwidth to less than Optane.
I thought I understood VMs and such. Either I don't or your comment is acronym barf that makes no sense. Someone please explain "write an AVX job to run on a VM and if run on the same CPU as your VM would reduce your memory latency and bandwidth to less than Optane." It just makes no sense to way it is said, who says "run on the same CPU as your VM"? and that "would reduce your memory latency and bandwidth? Huh?
AVX is an acronym for Advanced Vector Extensions, which are special instructions that perform vector math. Historically AVX has been aimed at multimedia applications, where algorithms like filters require dozens or hundreds of the same math performed on each pixel or audio sample. While the performance is amazing, because a single instruction can operate on 128 to 512 bit vectors of packed data, the functions are fairly simple and only really apply to certain types of applications. It's no replacement for general purpose computing.
An "AVX job" would presumably be a program someone has written to leverage AVX instructions to speed up a massive computation. While multimedia has typically been the main use for AVX, modern AI frameworks like Tensorflow (a keyword to google...) can leverage AVX to speed up neural network computation. So it's quite possible someone might try to make heavy use of AVX512 on a server.
I believe an implicit assumption here could be called "Process CPU Affinity" (another term to give to google....) And of course the pretty obvious practice of VPS providers to run more virtual machines on their servers than non-hyperthread CPU cores. If these conditions are true, then it would seem likely your virtual machine would tend to time-slice with the same group of other customers' VPS instances on the same CPU core.
I personally do not have enough experience with AVX to know whether code using mostly AVX instructions would put an undue burned on the L1, L2, L3 caches and memory bus to the actual DRAM. But I have personally written quite a lot of signal processing code on embedded ARM microcontrollers, where sustaining enough read and write performance to the buffers with the signal data (or vectors in memory) is a huge issue. It's pretty easy to imagine AVX512 code could theoretically sustain a large number of row reads & writes as it grinds through incredible amount of vector data. If you're familiar with DDR DRAM timing numbers (usually 4 numbers advertised on consumer DDR DIMMs, each the number of cycles needed for a certain part of a row access), it's pretty easy to imagine a CPU core running lots of AVX instructions causing a large number of row reads and queuing lots of row write backs.
AVX also has earned a reputation for causing thermal problems, since an sustained set of AVX instructions (or "AVX job") places far more computation load on these CPUs than ordinary code.
Hopefully this helps explain", with the caveat that someone who's actually written & debugged & optimized code directly using AVX could probably speak more authoritatively to the memory bandwidth & latency impact on other code.
"I have a bad feeling about Optane. Something tells me that Xpoint will be sold as actual DRAM for entry level VMs on Azure, AWS and other cloud services."
I don't think you need to be worry about that - for one thing I don't believe the Optane memory can be used in same slot for DRAM. It appears that even if it is same slots - it requires special programming to access this memory. My feeling is that it will actually be used by VM's and that the system using will have extremely high performance transfer between normal ram and Optane memory.
Yes a system with 3.75 TB of DRAM will perform better than a system with 678G of DRAM and remainder with Optane memory - but think realistically - what kind of system would use 3.75 TB at the same time.
I see it as high performance cache that is slower than all DRAM but faster than SSD.
The following is information on SDK for programming this kind of memory
Yes, this won't be coming to a gaming rig near you, at least not near me or for me. Optane-type DIMM-formatted non-volatile memory is a niche product for a niche market, albeit a very lucrative one. The terabyte capacities become interesting if you are, for example, running HANA or similar very large high-availability databases. Customers that can afford the very expensive site licenses for those will also spring for top-end CPUs with all the frills, because it makes business sense. If millions of dollars are at stake, spending $ 150K and more on 1-2 TB ECC DRAM plus matching optane DIMMs is suddenly not that outrageous.
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Jhlot - Tuesday, July 10, 2018 - link
Speculation bandwagon, everyone hop on!PurpleTangent - Tuesday, July 10, 2018 - link
Intel continuing to be super disingenuous by implying that Optane is equivalent memory to DRAM.prisonerX - Tuesday, July 10, 2018 - link
But it's the same shape and size, and it's right there next to the DRAM.FunBunny2 - Tuesday, July 10, 2018 - link
and it does remember.HollyDOL - Wednesday, July 11, 2018 - link
Imagine all that po.. wer it can hold!cdillon - Tuesday, July 10, 2018 - link
Where are they implying this? Just because something fits into a DIMM socket doesn't imply that it's equivalent to DRAM, that would be an unfounded assumption.In all of the Optane marketing material that I have seen they mention that Optane fits a performance niche in between DRAM and NAND. That it is less-than-DRAM in the performance aspect, and more-than-DRAM in the capacity and non-volatile aspects.
wumpus - Tuesday, July 10, 2018 - link
I had written a fairly large comment defending Intel, then realized that I was almost positive there isn't any tag ram to use that DRAM like a cache. 3dxpt really *should* be the memory on these servers, but it looks like the only way to switch between them is either some sort of manual partition (which will probably work fine in practice with huge databases) or the same trick currently used in consumer trash with 3dxpt labled as "memory": simply use the 3dxpt as storage with a large virtual drive hanging off of it.Talk about baby steps, can they make this thing even more of a niche item?
PeachNCream - Tuesday, July 10, 2018 - link
Presumably the people purchasing a system with Optane sitting in DIMM slots would understand what they're buying and align the equipment to a role that properly leverages the hardware. This isn't like an end user picking up a Chromebook at WalMart that's surprised that it doesn't run Windows after unboxing it at home. I think to make the argument you're making ignores the target buyer knowledge base in order to justify what is otherwise unreasonable outrage over a new piece of technology that you strangely feel is some sort of threat to you.Elstar - Tuesday, July 10, 2018 - link
How long before someone points out the difference between terabytes (TB) and tebibytes (TiB)?jardows2 - Tuesday, July 10, 2018 - link
I think you just did.Mr Perfect - Wednesday, July 11, 2018 - link
Is that even relevant to RAM? I've only seen the distinction applied to storage.sandytheguy - Thursday, July 12, 2018 - link
RAM has always been measured in GiB/TiB, so whenever someone says GB it's safe to assume they mean GiB. Opposite for network bandwidth. It's those evil optical and magnetic storage companies that decided to confuse everyone.Joseph Luppens - Thursday, July 12, 2018 - link
https://mintywhite.com/vista/terabytes-tebibytes-h...SLB - Tuesday, July 17, 2018 - link
Right -- the correct number is 3.75 TB per socket (or better yet, 3.75 TiB). The article should be fixed.lilmoe - Tuesday, July 10, 2018 - link
I have a bad feeling about Optane. Something tells me that Xpoint will be sold as actual DRAM for entry level VMs on Azure, AWS and other cloud services.Zan Lynx - Wednesday, July 11, 2018 - link
So what?You do know that anyone could write an AVX job to run on a VM and if run on the same CPU as your VM would reduce your memory latency and bandwidth to less than Optane.
Jhlot - Saturday, July 14, 2018 - link
I thought I understood VMs and such. Either I don't or your comment is acronym barf that makes no sense. Someone please explain "write an AVX job to run on a VM and if run on the same CPU as your VM would reduce your memory latency and bandwidth to less than Optane." It just makes no sense to way it is said, who says "run on the same CPU as your VM"? and that "would reduce your memory latency and bandwidth? Huh?PaulStoffregen - Monday, July 30, 2018 - link
AVX is an acronym for Advanced Vector Extensions, which are special instructions that perform vector math. Historically AVX has been aimed at multimedia applications, where algorithms like filters require dozens or hundreds of the same math performed on each pixel or audio sample. While the performance is amazing, because a single instruction can operate on 128 to 512 bit vectors of packed data, the functions are fairly simple and only really apply to certain types of applications. It's no replacement for general purpose computing.An "AVX job" would presumably be a program someone has written to leverage AVX instructions to speed up a massive computation. While multimedia has typically been the main use for AVX, modern AI frameworks like Tensorflow (a keyword to google...) can leverage AVX to speed up neural network computation. So it's quite possible someone might try to make heavy use of AVX512 on a server.
I believe an implicit assumption here could be called "Process CPU Affinity" (another term to give to google....) And of course the pretty obvious practice of VPS providers to run more virtual machines on their servers than non-hyperthread CPU cores. If these conditions are true, then it would seem likely your virtual machine would tend to time-slice with the same group of other customers' VPS instances on the same CPU core.
I personally do not have enough experience with AVX to know whether code using mostly AVX instructions would put an undue burned on the L1, L2, L3 caches and memory bus to the actual DRAM. But I have personally written quite a lot of signal processing code on embedded ARM microcontrollers, where sustaining enough read and write performance to the buffers with the signal data (or vectors in memory) is a huge issue. It's pretty easy to imagine AVX512 code could theoretically sustain a large number of row reads & writes as it grinds through incredible amount of vector data. If you're familiar with DDR DRAM timing numbers (usually 4 numbers advertised on consumer DDR DIMMs, each the number of cycles needed for a certain part of a row access), it's pretty easy to imagine a CPU core running lots of AVX instructions causing a large number of row reads and queuing lots of row write backs.
AVX also has earned a reputation for causing thermal problems, since an sustained set of AVX instructions (or "AVX job") places far more computation load on these CPUs than ordinary code.
Hopefully this helps explain", with the caveat that someone who's actually written & debugged & optimized code directly using AVX could probably speak more authoritatively to the memory bandwidth & latency impact on other code.
But I'm going to go with not "acronym barf".
HStewart - Wednesday, July 25, 2018 - link
"I have a bad feeling about Optane. Something tells me that Xpoint will be sold as actual DRAM for entry level VMs on Azure, AWS and other cloud services."I don't think you need to be worry about that - for one thing I don't believe the Optane memory can be used in same slot for DRAM. It appears that even if it is same slots - it requires special programming to access this memory. My feeling is that it will actually be used by VM's and that the system using will have extremely high performance transfer between normal ram and Optane memory.
Yes a system with 3.75 TB of DRAM will perform better than a system with 678G of DRAM and remainder with Optane memory - but think realistically - what kind of system would use 3.75 TB at the same time.
I see it as high performance cache that is slower than all DRAM but faster than SSD.
The following is information on SDK for programming this kind of memory
https://www.snia.org/sites/default/orig/SDC2013/pr...
eastcoast_pete - Wednesday, July 11, 2018 - link
Yes, this won't be coming to a gaming rig near you, at least not near me or for me. Optane-type DIMM-formatted non-volatile memory is a niche product for a niche market, albeit a very lucrative one. The terabyte capacities become interesting if you are, for example, running HANA or similar very large high-availability databases. Customers that can afford the very expensive site licenses for those will also spring for top-end CPUs with all the frills, because it makes business sense. If millions of dollars are at stake, spending $ 150K and more on 1-2 TB ECC DRAM plus matching optane DIMMs is suddenly not that outrageous.