albertywu

echo "console.log(require('v8').getHeapStatistics())" | node - | grep heap_size_limit

# both max-old-space-size and max_old_space_size work
export NODE_OPTIONS="--max-old-space-size=16384"
export NODE_OPTIONS="--max_old_space_size=16384"

# alternatively, "node --max-old-space-size=16384 ..."

albertywu

Convert table t1 of this form:

id | p50 | p75 | p95
---------------------
1  | 10  | 11  | 12
2  | 13  | 14  | 15

into this form:

albertywu

# note: run as root

devicemount=/mnt
logicalname=/dev/md0

# get instance storage block devices
devices=( $(lsblk -o name,type,size,model,mountpoint | grep -i "NVMe Instance Storage" | awk '{print "/dev/"$1}') )

if [[ "${#devices[@]}" -gt 0 ]] ; then
  mkdir -p "$devicemount"

albertywu

cheat sheet for https://tldp.org/LDP/abs/html/parameter-substitution.html

---

Variable existence checking

${var:?}          # returns exit-code 1 if var not defined or null
${var:?err_msg}   # prints err_msg and returns exit-code 1 if var not defined or null

albertywu

# run a command inside a docker container
docker run --rm node ls

# run multiple commands inside a docker container
docker run --rm node bash -c "ls && pwd"

# pipe commands from stdin
echo "ls && pwd" | docker run --rm -i node bash

# pipe commands from script

albertywu

package main

import (
	"bytes"
	"fmt"
	"os"
	"os/exec"
	"strings"
)

albertywu

#!/bin/bash
# reproduces this failure locally: https://buildkite.com/uber/web-code-runner/builds/3499312#49338f5b-c4e8-4d4b-8b60-c2961f22657f

function docker_login_ecr {
  local DOCKER_CREDENTIAL_UBER_REGISTRY="027047743804.dkr.ecr.us-west-1.amazonaws.com"
  aws --region=us-west-1 ecr get-login-password | docker login --username AWS --password-stdin $DOCKER_CREDENTIAL_UBER_REGISTRY
}

docker_login_ecr # so we can pull down image from buildkite

albertywu

#!/bin/sh

# Called by "git push" after it has checked the remote status, 
# but before anything has been pushed.  

# If this script exits with a non-zero status nothing will be pushed.
#
# This hook is called with the following parameters:
#
# $1 -- Name of the remote to which the push is being done

albertywu

#!/usr/bin/env bash

# --- NORMAL-MODE BENCHMARKS ---
echo "--- web-code-base normal ---"
docker system prune --all --force
docker pull 027047743804.dkr.ecr.us-west-1.amazonaws.com/web-code-base@sha256:ddfb3a6aecf3fa9fbafceb600f5d670efed472196b0dc405fc23b897a2a100d1
time IMAGE="web-code-base:normal-build" docker-compose --file tools/ci/scripts/docker/docker-compose-base.yml build web-code-base

echo "--- web-code normal ---"
docker system prune --all --force 

albertywu

/**
 * Encodes a tree to a single string.
 *
 * @param {TreeNode} root
 * @return {string}
 */
var serialize = function(root) {
  let result = []