What is the competitive advantage of this versus NVMe? Their 1TB ramdisk is $1000, while a Gen 4 NVMe PCI-e card gives the same speeds in a smaller and more standard format for $150-$200.
I don't know if that is external data written, or also includes whatever overhead the drive's internal processes have, which I imagine is higher when you run it near max capacity.
RAM has virtually unlimited write endurance.
I was interested for CCTV recording, as it can be murder on standard HDDs and consumer SSDs. Continuous writing at whatever the total bitrate of all cameras is, plus whatever index you're using, plus whatever clips its generating.
Ideally HDD for the constant, SSD for the clips and index.
I had a small (120GB) clip and index SSD drive start to struggle in a dirt-cheap non-critical system and found it had written 42TB in a year. Now part of that was poor configuration, but the drive was REALLY starting to struggle, throughput would occasionally drop off a cliff.
The system was battery backed, so a RAM disk would have been fine, and on triggering the UPS I'd have it just copy the contents to a fast HDD.
Given that WD sells comparable TLC in their dual-port PCIe3 NVMe zoned namespace SSD with 10x the spec-sheet total drive writer, I'm not surprised.
These commands don't unnecessarily copy data.
Speaking as someone who actually runs NVMe RAIDs for large-ish databases, the NVMe speeds quoted are usually only attainable for large sequential streaming loads. While they are not spinning disks with heads that need to seek, there is still very substantial random I/O overhead with SSDs, including NVMe. Even with a top of the line model like a Samsung 980 Pro, you might only get 5% the PCIe 4 bus speed with heavy random IO performance.
RAM has cachelines and such, but postgres reading 8k at a time isn't limited by that.
How to work something like this into Linux as say, a very fast swap device, is another question.
The 980 Pro does way more with random reads of sufficient concurrency. The main issue is the 100us latency under load, so to get half a million IOPS, that's 50 concurrent requests. For maximum speed you need some batching I think.
RAM doesn't have a fixed number of write cycles. It can be written to indefinitely, but NVME flash has an estimated number of TBs that it can write before it fails.
RAM is volatile (the data is destroyed when the power is cut), which can be a security feature. There appears to be a battery backup on these boards, but I imagine that it can be removed easily.
Aside from what everyone else has stated, a ram disk like this seems to have a very very good rand4k speed, so it would be extremely useful for buffering high volume small size, erratic data loads while decreasing the number of writes to long term storage.
Samsung 980 Pro is under warranty up to 600 TBW.
I don't know if that is external data written, or also includes whatever overhead the drive's internal processes have, which I imagine is higher when you run it near max capacity.
RAM has virtually unlimited write endurance.
I was interested for CCTV recording, as it can be murder on standard HDDs and consumer SSDs. Continuous writing at whatever the total bitrate of all cameras is, plus whatever index you're using, plus whatever clips its generating.
Ideally HDD for the constant, SSD for the clips and index.
I had a small (120GB) clip and index SSD drive start to struggle in a dirt-cheap non-critical system and found it had written 42TB in a year. Now part of that was poor configuration, but the drive was REALLY starting to struggle, throughput would occasionally drop off a cliff.
The system was battery backed, so a RAM disk would have been fine, and on triggering the UPS I'd have it just copy the contents to a fast HDD.