11 ms·
Memristor-based non-volatile memory matches DRAM performance
- sschueller 15y agoVery interesting video on the memristor. Long but worth it: http://www.youtube.com/watch?v=bKGhvKyjgLY http://www.youtube.com/watch?v=bKGhvKyjgLY
- sceadu 15y agohttp://www.youtube.com/watch?v=QFdDPzcZwbs http://www.youtube.com/watch?v=QFdDPzcZwbs
- vsviridov 15y agoNo more RAM chip freezing to extract the encryption keys for Mr. Government Man...
- simias 15y agoThis is actually a valid point, most modern encryption schemes rely on the fact that the RAM can't be dumped easily. I guess you could keep at least some volatile memory for storing sensitive information such as encryption keys. Of course unless the rest of the MRAM is encrypted you may indeed leak potentially sensitive data. Maybe dedicated hardware could encrypt/decrypt the RAM contents on the fly when the CPU or the devices access it, but it sounds costly.
- wazoox 15y agoProcessor cache could easily hold the encryption keys. Now that memory controllers are integrated to modern CPUs, this could be achieved quite easily when revamping the architecture, adding a couple of special instructions.
- 4ad 15y agoNo new instructions necessary: http://www1.informatik.uni-erlangen.de/tresor http://www1.informatik.uni-erlangen.de/tresor .
- wazoox 15y agoOh yeah, silly me, I had forgotten about that. However, probably a couple of specialized instructions or storage areas in cache or register may make it a little more easy to use.
- simias 15y agoInteresting link. However it doesn't solve the security issues caused by non-volatile unencrypted system memory. I guess custom hardware could encrypt/decrypt the data going trough the memory controller on the fly.
- bwarp 15y agoThis is the next wave of technology. It solves so many fundamental problems. I can't wait to have a few GiB of MRAM in a workstation. Load/store architectures may go away due to this. Imagine 32Gb of CPU registers.
- justincormack 15y agoIt only said it wad RAM speed, not register or cache speed. There are speed of light constraints in the memory hierarchy too surely?
- bwarp 15y agoA memristor is a smaller and simpler component than once register cell. Due to this, leakage and speed of light are less of an issue than the current techology. I wouldn't expect replacement for a decade though.
- haberman 15y agoThat may be, but OP was talking about having 32 Gb of registers and obsoleting load/store instructions. Current technology doesn't have 32 Gb of SRAM in registers, it has less than 1k. Even if the cost of SRAM wasn't an issue, I would be surprised if you could increase the size of the register file by 30,000,000x while maintaining the same latency and throughput characteristics.
- bwarp 15y agoI was the the OP. The CPU spends a lot of time moving shit around rather than doing work. My point is to remove the distinction between the register file and the main memory so that the entire CPU's working set is linear and no copies are required, therefore drastically increasing speed. When you do this, you lose all the cache control latency and context switch overhead, resulting in a much smaller and faster core, leaving plenty of space for 32Gb on die :) No existing architectures will do this as they rely on the memory hierarchy. I'm talking about a new architecture.
- JumpCrisscross 15y ago"At present, the endurance of DRAM is effectively a lifetime of usage" Liked the article, but that's a self-referencing statement
- modeless 15y agoPerhaps they meant a human lifetime.
- AndrewDucker 15y agoIt means the lifetime of the system it's placed in. DRAM will last until you've thrown away all of the other bits of your system.
- ralfd 15y agoDRAM is also commonly sold with a "lifetime warranty", which means the lifetime that the RAM is being made at the factory and they have the reasonable ability to replace it.
- kzrdude 15y agoIt isn't. It introduces the term with quotes first: "endurance". Then this sentence defines what "endurance" means for DRAM.
- rcthompson 15y agoIt's still not a replacement for DRAM, though. The article says it can only take a million rewrites before failing. Depending on what a computer is doing, I'll bet the main memory can easily hit that limit in days to weeks.
- deleted 15y ago[deleted]
- kondro 15y agoIt is a replacement for SSD, not RAM (at least for now). Imagine your permanent storage being as fast as your RAM.
- Leynos 15y agoDo you think this will be a driving impetus for the move from SATA to PCI Express connected backing stores in consumer hardware?
- archivator 15y agoIs that really a possibility? I assumed the 6 Gb/sec (as Wikipedia claims) for SATA 3 would be sufficient bandwidth for any drive storage. I'll admit, I've not followed this sort of hardware closely but my understanding was that SATA is set on its own track, apart from the other buses like PCI and USB.
- jws 15y agoDDR-3's bandwidth is about 20 times SATA-3's. I'm sure people will make SATA SSD's. There is an architecture revolution to be had, but it isn't as easy carving off a high speed bus from the CPU and turning your database speed up to a factor of 20. If the write lifetime is a million writes, at 10ns/write you can burn that up in a millisecond.[1] Maybe you trust your server hardware to last for three years.[2] You get about 38 writes per hour. I hope you aren't syncing a critical chunk of data once a minute. So you have an insanely fast, nonvolatile store, but you can't just write to it willy-nilly. Let the engineering begin! (I'm sure it has for some people.) -- [1] Malware can be expensive in a hurry. A couple quick loops and you can ruin 1000 blocks/second. [2] If you have less than a few dozen servers you end up playing quality roulette. You have no idea which models from which vendors are going to hold up, so you make a guess based on reputation and price. Sometimes you are right, sometimes you are wrong. Sometimes you have a 50% mortality in 6 months. When you get a model that works well, by the time you know it lasts, you can't buy it any more. My strategy was always to buy a batch, run them in non-critical positions for 6 months to screen for early failures, if they were good, move the critical functions to them, but then get off of them before the age related failures begin. Three years was about my limit.
- cs702 15y agoMemristors will have a major impact on hardware architecture in the near to medium term. They promise permanent storage not just without the costs imposed by SSD (much slower performance than DRAM), but also random access without the costs imposed by hard drives (variable seek times depending on how data happens to be laid out on physical discs). IMHO the impact on software architecture is likely to be much less pronounced at first, because software ecosystems -- OS kernels, libraries, utilities, applications, etc. -- can evolve only gradually over a period of many years. Consider that Ken Thompson and Dennis Ritchie reportedly created the /usr directory because they ran out of space on a 1.5MB hard disk (!) more than 40 years ago (!), yet we're still living with this directory ( see http://lists.busybox.net/pipermail/busybox/2010-December/074114.html http://lists.busybox.net/pipermail/busybox/2010-December/074... ).