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---- MODULE GCD ----

EXTENDS Integers, TLC

Divides(p, n) == \E q \in -1000..1000 : n = q * p

DivisorsOf(n) == {p \in -1000..1000 : Divides(p, n)}

SetMax(S) == CHOOSE i \in S : \A j \in S : i >= j

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INIT
Init

NEXT
Next

INVARIANT
TypeOK

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INIT
Init

NEXT
Next

INVARIANT
TypeOK

CONSTANTS

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Internet Scale Services Checklist

A checklist for designing and developing internet scale services, inspired by James Hamilton's 2007 paper "On Desgining and Deploying Internet-Scale Services."

• http://mvdirona.com/jrh/talksandpapers/jamesrh_lisa.pdf

Basic tenets

• Does the design expect failures to happen regularly and handle them gracefully?
• Have we kept things as simple as possible?

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#!/bin/bash

USR=$1

su $USR --shell /bin/bash --comman "ulimit -n"

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Set values in:

/etc/security/limits.conf

Needs to be enabled in:

/etc/pam.d/common-session
/etc/pam.d/common-session-noninteractive

by adding:

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# Use white space as delimiter and return the 1st
# field and all fields including and after the
# 7th field.

cut -d' ' -f1,7-

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// Copyright 2012, Google Inc. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Write file to temp and atomically move when everything else succeeds.
func WriteFileAtomic(filename string, data []byte, perm os.FileMode) error {
	dir, name := path.Split(filename)
	f, err := ioutil.TempFile(dir, name)
	if err != nil {
		return err

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{-# LANGUAGE OverloadedStrings #-}

-- | Wai+Warp file server with routes. Used GHC 7.4, Wai 1.1, Warp 1.1 versions.
module Main where

import Network.HTTP.Types (status200)
import Network.Wai (Application,responseLBS)
import Network.Wai.Middleware.Router (router,dir)
import Network.Wai.Handler.Warp (run)
import Network.Wai.Application.Static 

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{-# LANGUAGE OverloadedStrings #-}

-- | Converts a matrix represented as text to Hmatrix Matrix. Used GHC 7.4, Hmatrix 0.14.
module Main where

import qualified Data.Text as T
import qualified Data.Text.IO as TIO
import Data.Text (Text,splitOn,lines)
import Data.Text.Read (double)
import Data.Packed.Matrix (Matrix,fromLists)