benchcmp: 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/bin/benchcmp - from package: golang-googlecode-tools-benchcmp

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

On Debian possible default full paths are:

/usr/bin/benchcmp - from package: golang-go.tools

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

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