azat

#include <atomic>
#include <bits/types/clockid_t.h>
#include <cstdint>
#include <cstdlib>
#include <ctime>
#include <cerrno>
#include <iostream>
#include <list>
#include <random>
#include <sched.h>

azat

#!/usr/bin/env bash

# Measure overhead of fsync_part_directory for SELECTs from MergeTree/ReplicatedMergeTree (due to rename under lock)
# Refs: https://github.com/ClickHouse/ClickHouse/pull/64955

set -e

bin=$1 && shift
id=$BASHPID

azat

#!/usr/bin/env bash

# This is wrapper for faster addr2line, that is required for "perf --call-graph dwarf"
# NOTE: since v6.3 perf supports specifying addr2line and supports LLVM so it is not required there

# stdbuf is important here to avoid buffering, otherwise perf will stuck
stdbuf -o0 -i0 sed -e 's/,//' -e 's/^$/ffffffffffffff/' | llvm-addr2line "$@"

azat

#include <boost/smart_ptr/detail/spinlock.hpp>
#include <cstdint>
#include <cstring>
#include <cassert>
#include <iostream>
#include <list>
#include <mutex>
#include <optional>
#include <shared_mutex>
#include <thread>

azat

$ lscpu -J | jq '.lscpu.[] | select(.field == "Model name:").data' -r
AMD Ryzen Threadripper PRO 5975WX 32-Cores
$ musl-clang -static -O3 -o test-syscalls test-syscalls.cpp
$ ldd test-syscalls
        not a dynamic executable
$ ./test-syscalls
gettid: 48735.848us, 20518777.061 cps, 48.736 ns per call
clock_gettime (VDSO): 20660.516us, 48401501.686 cps, 20.661 ns per call
nothing_indirect_call: 0.020us, 50000000000000.000 cps, 0.000 ns per call
nothing: 0.020us, 50000000000000.000 cps, 0.000 ns per call

azat

#include <cstdint>
#include <ctime>
#include <cerrno>
#include <iostream>
#include <utility>

uint64_t now_ns(clockid_t clock)
{
    struct timespec ts;
    clock_gettime(clock, &ts);

azat

#include <cstdint>
#include <ctime>
#include <iostream>
#include <sys/types.h>
#include <thread>
#include <list>

uint64_t now_ns()
{
    struct timespec ts;

azat

#!/usr/bin/env python

# Based on https://github.com/goldshtn/linux-tracing-workshop
# Based on https://gist.github.com/SaveTheRbtz/807be09f73d13b80e429d45bd1707e00

"""
The MIT License (MIT)

Copyright (c) 2017 Sasha Goldshtein
Copyright (c) 2018 Alexey Ivanov

azat

#include <bits/time.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <time.h>

// https://igoro.com/archive/gallery-of-processor-cache-effects/

u_int64_t now_ns()

azat

#include <bits/time.h>
#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <sys/types.h>
#include <time.h>

// Answers the question "Does cache oblivious in jemalloc still make sense?"
// The short answer is "Yes"!
//