mfleming’s gists

mfleming / Dockerfile.perf

Created March 27, 2024 22:53

	FROM ubuntu AS build

	RUN apt-get update
	RUN apt-get install -y git-core make gcc make flex bison pkg-config
	RUN git clone git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
	RUN NO_LIBTRACEEVENT=1 NO_JEVENTS=1 NO_LIBELF=1 make -C linux/tools/perf

	FROM ubuntu
	COPY --from=build linux/tools/perf/perf /bin/perf
	ENTRYPOINT ["/bin/perf", "bench", "sched", "pipe"]

mfleming / big-oh-n3.py

Created May 3, 2023 11:43

	#!/usr/bin/env python3
	#
	# Build three lists of integers with NUM_ELEMS elements where each element is a random integer in
	# the range [0,9223372036854775807]. Then measure the time to iterate over all three lists in a
	# O(n^3) loop.

	import random
	import sys
	import time

mfleming / futex-hrtimer-details.py

Created September 8, 2021 13:52

	#!/usr/bin/env python3
	#
	# Copyright 2021 Matt Fleming
	#
	# Licensed under the Apache License, Version 2.0 (the "License");
	# you may not use this file except in compliance with the License.
	# You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#

mfleming / aug-19-script

Created August 19, 2020 13:53

	#!/bin/bash

	mins=10

	echo "Collecting metrics for $mins minutes..."
	dstat_outfile="dstat-`hostname`.csv"
	echo "Writing dstat output to $dstat_outfile"
	#dstat --output $dstat_outfile -pmgsdr --disk-util -nyct -C $(seq --separator=, 0 `grep -c processor /proc/cpuinfo`),total 1 $mins*60 &
	dstat --output "dstat-`hostname`.csv" -pmgsdr --disk-util --disk-avgqu --disk-avgrq --disk-svctm --disk-tps --disk-wait -nyct -C $(seq --separator=, 0 `grep -c processor /proc/cpuinfo`),total 1 $mins*60 &

mfleming / local read p95

Created August 18, 2020 09:04

mfleming / local write p95

Created August 18, 2020 09:04

mfleming / p95 read latency

Created August 18, 2020 09:02

mfleming / p95 write latency

Created August 18, 2020 09:02

mfleming / jmx-metrics

Created August 17, 2020 15:06

	#!/bin/bash

	mins=60

	echo "Collecting metrics for $mins minutes..."
	dstat_outfile="dstat-`hostname`.csv"
	echo "Writing dstat output to $dstat_outfile"
	dstat --output $dstat_outfile -pmgsdr --disk-util -nyct -C $(seq --separator=, 0 `grep -c processor /proc/cpuinfo`),total 1 $mins &

	latency_outfile="jmx-lat-`hostname`.csv"

mfleming / objdump-clear_user.txt

Created May 7, 2020 12:18

This file has been truncated, but you can view the full file.


	clear_user: file format elf64-x86-64


	Disassembly of section .init:

	0000000000005718 <_init>:
	5718: 48 83 ec 08 sub $0x8,%rsp
	571c: 48 8b 05 c5 08 25 00 mov 0x2508c5(%rip),%rax # 255fe8 <__gmon_start__>
	5723: 48 85 c0 test %rax,%rax

Matt Fleming mfleming