18 ms·
No. "io_uring faster than mmap" is sort of a truism: sequential page faults are slower than carefully orchestrated async I/O. The point of the article is that r
by nine_k 1y ago
No. "io_uring faster than mmap" is sort of a truism: sequential page faults are slower than carefully orchestrated async I/O. The point of the article is that reading directly from a PCIe device, such as an NVMe flash, can actually be faster than caching things in RAM first.
- wmf 1y agoreading directly from a PCIe device, such as an NVMe flash, can actually be faster than caching things in RAM first. That's not true though, because the PCIe device DMAs into RAM anyway.
- nine_k 1y agoNo, it can DMA straight into L3 cache, as mentioned in the article. See https://www.intel.com/content/www/us/en/io/data-direct-i-o-technology.html https://www.intel.com/content/www/us/en/io/data-direct-i-o-t...