Brendan Gregg

SEPTEMBER 25, 2021

Since instances of both CentOS and Ubuntu were running in parallel, I could collect flame graphs at the same time (same time-of-day traffic mix) and compare them side by side. As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI. But I'm not completely sure.

Speed 126

Speed Java AWS Virtualization 126

Brendan Gregg

SEPTEMBER 5, 2017

Linux has been adding tracing technologies over the years: kprobes (kernel dynamic tracing), uprobes (user-level dynamic tracing), tracepoints (static tracing), and perf_events (profiling and hardware counters). In a test environment, I've seen several more Linux panics in the past three years.

Virtualization 76

Virtualization AWS Engineering Hardware 76

Brendan Gregg

SEPTEMBER 25, 2021

Since instances of both CentOS and Ubuntu were running in parallel, I could collect flame graphs at the same time (same time-of-day traffic mix) and compare them side by side. As a Xen guest, this profile was gathered using perf(1) and the kernel's software cpu-clock soft interrupts, not the hardware NMI. But I'm not completely sure.

Speed 40

Speed Java AWS Virtualization 40

Smashing Magazine

JANUARY 7, 2019

For Mac OS, we can use Network Link Conditioner , for Windows Windows Traffic Shaper , for Linux netem , and for FreeBSD dummynet. On the other hand, we have hardware constraints on memory and CPU due to JavaScript parsing times (we’ll talk about them in detail later). Lighthouse , a performance auditing tool integrated into DevTools.

Performance 104

Performance Cache Metrics Network 104