4 ms·

Benchmarks aside, does PCIe 4.0 show any real-world noticeable performance gains over PCIe 3.0 (let alone SATA)?

loeg 6y ago
Any rate above ~3.8GB/s is impossible on PCIe 3.0 x4. These things clear 4-5 GB/s with large block sizes, especially on sequential reads. It's probably workload dependent whether you'll see much use out of the PCIe 4.0 (over 3.0) with these particular devices. > (let alone SATA) NVMe is (very) noticeably faster than SATA, especially for random IO, but also for sequential io patterns. Multiple queues and reduced protocol latency go a long way. SATA III throughput maxes out at 600 MB/s. In comparison, these drives do 4000-5000 MB/s.
AdrianB1 6y ago
It mostly depends on the workload. For the typical PC, no. I have some real life cases at work where the performance difference is more than noticeable, but that is a relatively small percentage of workload.
the8472 6y ago
Workloads aren't just about sustained bandwidth. The available bandwidth and IOPS also determine how fast a burst can be finished. OS hibernation, application startup, loading game/3D assets, system updates (unless you're on windows), autosave features, ripgrep... They all can saturate some of those limits momentarily. And those moments gets shorter if you have more bandwidth and lower latency. avg-cpu: %user %nice %system %iowait %steal %idle 0.19 0.00 1.96 1.21 0.00 96.64 Device r/s rkB/s rrqm/s %rrqm r_await rareq-sz w/s wkB/s wrqm/s %wrqm w_await wareq-sz d/s dkB/s drqm/s %drqm d_await dareq-sz f/s f_await aqu-sz %util nvme0n1 4180.00 332544.00 0.00 0.00 0.21 79.56 2518.00 1332796.00 74.00 2.85 6.89 529.31 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 18.21 81.60 it's wrapping code blocks :( you had one job.

loeg 6y ago

Any rate above ~3.8GB/s is impossible on PCIe 3.0 x4. These things clear 4-5 GB/s with large block sizes, especially on sequential reads. It's probably workload dependent whether you'll see much use out of the PCIe 4.0 (over 3.0) with these particular devices. > (let alone SATA) NVMe is (very) noticeably faster than SATA, especially for random IO, but also for sequential io patterns. Multiple queues and reduced protocol latency go a long way. SATA III throughput maxes out at 600 MB/s. In comparison, these drives do 4000-5000 MB/s.

AdrianB1 6y ago

It mostly depends on the workload. For the typical PC, no. I have some real life cases at work where the performance difference is more than noticeable, but that is a relatively small percentage of workload.

the8472 6y ago

Workloads aren't just about sustained bandwidth. The available bandwidth and IOPS also determine how fast a burst can be finished. OS hibernation, application startup, loading game/3D assets, system updates (unless you're on windows), autosave features, ripgrep... They all can saturate some of those limits momentarily. And those moments gets shorter if you have more bandwidth and lower latency. avg-cpu: %user %nice %system %iowait %steal %idle 0.19 0.00 1.96 1.21 0.00 96.64 Device r/s rkB/s rrqm/s %rrqm r_await rareq-sz w/s wkB/s wrqm/s %wrqm w_await wareq-sz d/s dkB/s drqm/s %drqm d_await dareq-sz f/s f_await aqu-sz %util nvme0n1 4180.00 332544.00 0.00 0.00 0.21 79.56 2518.00 1332796.00 74.00 2.85 6.89 529.31 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 18.21 81.60 it's wrapping code blocks :( you had one job.