rw-by-pid-report: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/libexec/perf-core/scripts/perl/bin/rw-by-pid-report - from package: perf

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/share/perf_3.16-core/scripts/perl/bin/rw-by-pid-report - from package: linux-tools-3.16

You may install the required package with command apt-get install {package}

Error in other languages:
rw-by-pid-report: bevel nie gevind nie
rw-by-pid-report: comandă negăsită
rw-by-pid-report: comando não encontrado
rw-by-pid-report: commande introuvable
rw-by-pid-report: command not found
rw-by-pid-report: käsku ei ole
rw-by-pid-report: không tìm thấy lệnh
rw-by-pid-report: komanda nerasta
rw-by-pid-report: Kommando nicht gefunden.
rw-by-pid-report: kommandot finns inte
rw-by-pid-report: komut yok
rw-by-pid-report: nie znaleziono polecenia
rw-by-pid-report: níor aimsíodh an t-ordú
rw-by-pid-report: no se encontró la orden
rw-by-pid-report: no s'ha trobat l'ordre
rw-by-pid-report: opdracht niet gevonden
rw-by-pid-report: parancs nem található
rw-by-pid-report: perintah tidak ditemukan
rw-by-pid-report: príkaz nenájdený
rw-by-pid-report: příkaz nenalezen
rw-by-pid-report: команда не найдена
rw-by-pid-report: командата не е открита
rw-by-pid-report: 命令找不到
rw-by-pid-report: コマンドが見つかりません