Earlier quoted context omitted.
Still waiting for the Memristor...
Oh jeez I was so excited for that!
At first I was resistant but now I am charged for it.
Rest in Peace, Optane
81–90 of 122 posts
Re: Rest in Peace, Optane
#82Optane suffered the same fate as every other storage technology over the decades with a similar value proposition. Broadly, the notional value of storage technology like Optane is that it offers a drop-in improvement in storage performance without requiring any software modification, albeit at a significant cost premium. The theory that this market exists in any significant way never pans out in practice. On one hand…
" The theory that this market exists in any significant way never pans out in practice. " The transition from HDD to SSD technology is a counter example to your claim. It was a drop-in replacement (same SATA interface) and the tech significantly improved performance without any other software modification needed.
SSDs are orders of magnitude faster than HDD, enough to justify the cost differential and investments to rethink the software stack.
Octane was an incremental improvement in performance when compared to SSD, and in cost when compared to RAM. An awkward spot to be in.
Re: Rest in Peace, Optane
#83Earlier quoted context omitted.
Interactively, it felt like they were slower than even a sun 3. I know this isn't scientific, but I never metered it. Seymour Cray's CDC machines were fast computers, but IMHO those Cray Corp machines were essentially high performance vector units that happened also to be able to run a bit of control code. I guess it wasn't sexy enough to build a coprocessor, or maybe by then there was enough choice in mainframes tha…
We weren’t building them to be interactive dedicated mostly-idle personal computers with snappy response times, and that’s not why they were purchased.
I’m not disagreeing with you! I don’t really understand why people wanted it — it wasn’t what the machine was designed for.
I mean, I do understand (but disagree with) the specific use case at NASA where I encountered it: the CFD would run all night (or longer) and when done the files went to some Irises for visualization, which also took forever. So running the same source code (basically rsync iirc) sounds easier in theory. But at what cost? I think it would have been better to just write the transfer code to run under Cray OS.
And indeed, once unicos was on the machine people did want to run it interactively.
Re: Rest in Peace, Optane
#84Optane is dead. Long live Optane! PCIE 3.0 Optane recently sold so well it got backordered and the price popped. (Ok maybe it was LevelOneTechs Wendell? Maybe it was organic? https://www.newegg.com/intel-optane-905p-1-5tb/p/N82E1682016... ) Today PCIE 4.0 prices have fallen so fast that you can RAID0 a few M.2s and get about the same IOPs from a single Optane drive for a similar $ per GB, though not exactly the same…
I’ve been using them on SBCs for that reason - on pcie 3 you still get the latency benefits even if throughput isn’t there.
Re: Rest in Peace, Optane
#85Why was everyone so obsessed with the idea of Optane as universal memory? From a consumer perspective, it was a fast small SSD that doesn't wear out. That was enough to justify it's value at the prices it went for(Or at least it seems like it, I never personally used it). It didn't need any radical rethink of computing to be worth it. I'm not even a fan of the nonvolatile RAM idea. Rebooting is often the first thing…
> Rebooting is often the first thing we do to fix stuff.
Depends on the environment. That used to be the common approach for windows, less so for *nix systems.
Re: Rest in Peace, Optane
#86Earlier quoted context omitted.
mmap on Optane direct-access-aware (DAX) filesystems like EXT4/XFS now, is not like mmap on block devices where the OS gets in your way and pages stuff in from disk and (maybe) later syncs it back to persistent storage. Optane is the persistent storage, it's just usable/addressable as regular RAM as it's plugged in to DIMM slots. And in the later Xeon architecture (Xeon Scalable 3rd gen, I think), intel expanded the…
> mmap on Optane direct-access-aware (DAX) filesystems like EXT4/XFS now, is not like mmap on block devices where the OS gets in your way and pages stuff in from disk Yes, the real case for Optane memory is that, supposedly, you don't have to fsync(). And insisting on proper fsync() tends to tank the performance of even the fastest NVMe SSD's. So the argument for a real, transformative performance improvement is ther…
Why would you not have to fsync? The fsync is a memory barrier that is just as useful with octane to ensure integrity.
Do you mean the latency of ensuring fsync safety is lower?
Re: Rest in Peace, Optane
#87Why was everyone so obsessed with the idea of Optane as universal memory? From a consumer perspective, it was a fast small SSD that doesn't wear out. That was enough to justify it's value at the prices it went for(Or at least it seems like it, I never personally used it). It didn't need any radical rethink of computing to be worth it. I'm not even a fan of the nonvolatile RAM idea. Rebooting is often the first thing…
I've always thought this would be perfect for something like Redis to run on top of.
You wouldn't have to necessarily worry about DB dumps since the backing storage would still be very fast but could survive reboots.
Re: Rest in Peace, Optane
#88What was interesting about Optane was that it was kinda an attempt to get rid of disk and ram distinction. You had single device (optane stick) which served as both - ram and disk. After decades of current approach we finally could physically get rid of disks - hdds, ssds or even nvme sticks. https://www.theregister.com/2022/08/01/optane_intel_cancella... >Optane presented a radical, transformative technology but bec…
Still waiting for the Memristor...
Optane was probably a memristor technology under the hood.
Re: Rest in Peace, Optane
#89It's not just Optane. There have been other NVRAM technologies that were hyped as "fast as SRAM, persistent as HDDs, cheap and dense as DRAM" over the years such as FeRAM and MRAM. MRAM exists as a commercial product but it still fails to deliver on the cheap/dense part.
FRAM and MRAM have found a place in embedded markets doing weird things - MRAM is a low-cost alternative to space-grade flash right now, and both FRAM and MRAM are used for small, fast persistent "caching" with good wear-out. Optane was the only one of these products that was really targeted at the server space, and had much better density than FRAM, MRAM, PCM, and all the other weird alternatives.
Re: Rest in Peace, Optane
#90What was interesting about Optane was that it was kinda an attempt to get rid of disk and ram distinction. You had single device (optane stick) which served as both - ram and disk. After decades of current approach we finally could physically get rid of disks - hdds, ssds or even nvme sticks. https://www.theregister.com/2022/08/01/optane_intel_cancella... >Optane presented a radical, transformative technology but bec…
> What was interesting about Optane was that it was kinda an attempt to get rid of disk and ram distinction.
That might be the promise, but that premise is fundamentally flawed. I mean, what drives the need to classify memory devices is performance characteristics, and even if your starting point is this idealized world where Optane was ubiquitous then all it took was a ephemeral memory technology to significantly outperform Optane to create need support the performance-oriented non-persistent memory type.