3 ms·
How does this map to the current state of commodity computing? For example, it seems we already achieved that with disks, once embedded controllers attached to
by mmt 8y ago
How does this map to the current state of commodity computing?
For example, it seems we already achieved that with disks, once embedded controllers attached to DMA-capabled HBAs became the norm.
A similar thing seems to have happened with NICs, as well as the ability to offload higher-level protocol processing (another mainframe-like feature).
- nickpsecurity 8y agoThe Channel I/O worked on many devices and the OS. Far as cost, using AWS might not be cheap but I was thinking redundant VM's or dedi's with cost-effective hosts. That doesnt cost hundreds of thousands to millions a year.
- mmt 8y agoPerhaps I'm missing something. I'm still unsure if you're saying that Channel I/O (or its equivalent) is missing from current x86 server systems. Does virtualization affect this situation? Initially, you mentioned high utilization ratio and throughput. I think the former is a red herring [1], but I'm curious about the latter. I've certainly witnessed poorer I/O throughput under virtualization, but on bare metal, throughput doesn't seem to be limited (beyond the capabilities of the bus). [1] e.g. it doesn't matter if CPU is pegged but I/O channels are at 10% if the workload is CPU-bound and CPUs are the expensive part to scale. Or substitute memory for CPU.