Mohamed3on

Studying for a Tech Interview Sucks, so Here's a Cheat Sheet to Help

This list is meant to be a both a quick guide and reference for further research into these topics. It's basically a summary of that comp sci course you never took or forgot about, so there's no way it can cover everything in depth. It also will be available as a gist on Github for everyone to edit and add to.

Data Structure Basics

Array

Definition:

• Stores data elements based on an sequential, most commonly 0 based, index.
• Based on tuples from set theory.

chewbranca

On the Viability of Erlang Releases and CouchDB

There has been some discussion on what versions of Erlang CouchDB should support, and what versions of Erlang are detrimental to use. Sadly there were some pretty substantial problems in the R15 line and even parts of R16 that are landmines for CouchDB. This post will describe the current state of things and make some potential recommendations on approach.

Scheduler Collapse

tsiege

ANNOUNCEMENT

I have moved this over to the Tech Interview Cheat Sheet Repo and has been expanded and even has code challenges you can run and practice against!






\

angrycub

#!/usr/bin/env escript -f
%% -*- erlang -*-
 
-define(OFFSETFIELD,  64).
-define(TSTAMPFIELD,  32).
-define(KEYSIZEFIELD, 16).
-define(TOTALSIZEFIELD, 32).
 
-define(HINTHEADSIZE, 18). %%(?TSTAMPFIELD + ?KEYSIZEFIELD + ?TOTALSIZEFIELD + ?OFFSETFIELD)/8

lukebakken

Testing Notes

At this time only the protocol buffers client supports client certificates. HTTP is not supported.

Setup

Setting up a Root CA

It is necessary to set up a Root Certificate authority to be able to create and sign certificates.

mranney

dtrace -n 'syscall::writev:entry /execname == "node" && arg2 > 16/ { printf("iovcnt: %d", arg2); }' -n 'syscall::writev:return /execname == "node" && arg1 == -1 && errno == 22/ { printf("%s %s %d\\n", curpsinfo->pr_psargs, probefunc, errno); jstack(100, 8000); }'  
  1  10260                     writev:entry iovcnt: 57
  1  10261                    writev:return node --nouse-idle-notification /voxer/server/node_router/node_router.js /voxer/ writev 22\n
              libc.so.1`__writev+0x15
              node`uv__write.part.5+0x18f
              node`uv_write2+0x1b9
              node`uv_write+0x35
              node`_ZN4node10StreamWrap6WritevERKN2v89ArgumentsE+0x678
              node`_ZN2v88internalL21Builtin_HandleApiCallENS0_12_GLOBAL__N_116BuiltinArgumentsILNS0_21BuiltinExtraArgumentsE1EEEPNS0_7IsolateE+0x157
              << internal code >>

macintux

• https://ferd.ca/a-distributed-systems-reading-list.html
• http://the-paper-trail.org/blog/distributed-systems-theory-for-the-distributed-systems-engineer/
• https://github.com/palvaro/CMPS290S-Winter16/blob/master/readings.md
• http://muratbuffalo.blogspot.com/2015/12/my-distributed-systems-seminars-reading.html
• http://christophermeiklejohn.com/distributed/systems/2013/07/12/readings-in-distributed-systems.html
• http://michaelrbernste.in/2013/11/06/distributed-systems-archaeology-works-cited.html
• http://rxin.github.io/db-readings/
• http://research.microsoft.com/en-us/um/people/lamport/pubs/pubs.html
• http://pdos.csail.mit.edu/dsrg/papers/
• http://scalingsystems.com/2011/09/07/reading-list-for-distributed-systems/

macintux

#!/usr/bin/perl -w

use strict;
use warnings;

sub usage {
    my ($errmsg) = @_;
    my $msg = <<END;
Usage: split-info <info file> <output directory>

cdahlqvist

%% -------------------------------------------------------------------
%%
%% pb_status_monitor: PoolBoy pool monitor
%%
%% Copyright (c) 2013 Basho Technologies, Inc. All Rights Reserved.
%%
%% This file is provided to you 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

freerobby

# This function uses net::http streaming and the Riak HTTP endpoint
# to export all keys in a riak bucket into a newline-delimited file.
 
require 'json'
require 'net/http'
 
RIAK_ROOT = 'http://localhost:8098'
 
# bucket: The bucket to export
# path: The folder into which to put the output file