🔍 Introduction If you've ever used a bottleneck calculator, you've probably seen a simple percentage telling you whether your CPU or GPU is holding your system back. But here’s the truth most people don’t realize: Bottlenecks are not fixed numbers — they are dynamic, workload-dependent behaviors. In this post, we’ll go beyond basic tools and break down how CPU and GPU bottlenecks actually work in…
The server is on a Gbit link. ethtool confirms 1000 Mbps on the interface. And yet every SFTP transfer caps out somewhere around 800 KB/s. Not 80 MB/s — 800 kilobytes per second. Less than 1% of the theoretical capacity. The problem isn't bandwidth. It's a stack of bad defaults: a congestion control algorithm designed for year-2000 networks, microscopically small NIC ring buffers, and application…
When your profiler swears everything’s fast but your metrics are screaming bloody murder eBPF From Rust: The 34ms Ghost We Couldn’t See When your profiler swears everything’s fast but your metrics are screaming bloody murder eBPF provides kernel-depth observability without overhead — tracing from userspace through syscalls to kernel internals reveals bottlenecks invisible to traditional profilers…
