84% of a single-threaded 1KB write in Redis is spent in the kernel

from blog Alex Clemmer, | ↗ original
The performance of live site systems — everything from K/V stores to lock servers — is still measured principally in latency and throughput. Server I/O performance still matters here. It is impossible to do well on either of these metrics without a performant I/O subsystem. Oddly, while the last 10 years have seen remarkable improvements in the...