Get CPU usage via SSH

Question

I want to retrieve the CPU utilization percentage via SSH and I have tried the command "top" but it will not let me.

I am using CentOS 6.

I tried this code

$connection = ssh2_connect("IP", PORT);
ssh2_auth_password($connection, "root", "PASS");
$stream = ssh2_exec($connection, "top");
$errorStream = ssh2_fetch_stream($stream, SSH2_STREAM_STDERR);

// Enable blocking for both streams
stream_set_blocking($errorStream, true);
stream_set_blocking($stream, true);

// Whichever of the two below commands is listed first will receive its appropriate output.  The second command receives nothing
echo "Output: " . stream_get_contents($stream);
echo "Error: " . stream_get_contents($errorStream);

// Close the streams        
fclose($errorStream);
fclose($stream);

But its every time give me an error: Output: Error: TERM environment variable not set.

I'm using PHP.

Answer 1

Thanks everyone but I managed. I did this command:

top -b -n 10 -d.2 | grep 'Cpu' |  awk 'NR==3{ print($2)}'

Answer 2

you can use

top -n 1
mpstat
iostat

Answer 3

phpseclib, a pure PHP SSH implementation, has a nifty discussing of how to do top in PHP with it:

http://phpseclib.sourceforge.net/ssh/pty.html#top

ie. you need a PTY.

$ssh->enablePTY();
$ssh->exec('top');
$ssh->setTimeout(5);
$ansi->appendString($ssh->read());
echo $ansi->getScreen();

You can do it with interactive mode too:

$ansi->appendString($ssh->read('username@username:~$'));
$ssh->write("top\n");
$ssh->setTimeout(5);
$ansi->appendString($ssh->read());
echo $ansi->getScreen();

Note that the output will have ANSI escape codes. Here's an example of what it'll look like if the ANSI escape codes are rendered to HTML:

http://phpseclib.sourceforge.net/ssh/examples.html#top

Answer 4

top shows CPU load in current moment, thus it may mislead, when there is processes which use CPU not continuously.

cat /proc/loadavg | awk '{print $1, $8}'

• will output average system load for 1 last minute. For idle system it will be 0.0, for loaded system it will be 0.5, 1.5 and above. when heavy task launched - it will instantly jump above 0.1.

to wait for idle system I use:

  while true
  do
    load=`cat /proc/loadavg | awk '{print $1, $8}'`
    if (( $(echo "$load < 0.05" |bc -l) )); then
      break
    fi
    echo -ne "Waiting for idle system: $load> 0.05... \033[0K\r"
    sleep 1
  done

Answer 5

Even better would be to simply install glances.

sudo apt install glances

Then simply run glances. Then your output would look like this. You can change the update speed.

$yourhostname - IP x.x.x.x/x Pub xx.xxx.xxx.xxx                  Uptime: 0:41:24

CPU  [  1.4%]   CPU -     1.4%  MEM -   10.8%  SWAP -    0.0%  LOAD    12-core
MEM  [ 10.7%]   user:     1.0%  total:  31.4G  total:   2.00G  1 min:    0.71
SWAP [  0.0%]   system:   0.4%  used:   3.38G  used:        0  5 min:    0.73
                idle:    98.5%  free:   28.0G  free:    2.00G  15 min:   0.69

NETWORK     Rx/s   Tx/s   TASKS 322 (1136 thr), 1 run, 235 slp, 86 oth 
eno1          0b     0b
lo           2Kb    2Kb   Systemd          6    Services loaded: 190 active: 190
_xxxxxxxx     0b    4Kb
                            CPU%  MEM%   PID USER        NI S Command 
DefaultGateway     62ms      4.2   0.9  1923 xxx          0 S cinnamon --replace
                             2.9   0.1  9055 xxx          0 R /usr/bin/python3 /
DISK I/O     R/s    W/s      1.9   0.5  1323 root         0 S /usr/lib/xorg/Xorg
disk1          0    91K      1.3   0.0  1338 root         0 S irq/74-nvidia
partition1     0      0      1.3   0.1  8586 xxx          0 S /usr/lib/gnome-ter
partition2     0    91K      1.0   0.4  8907 xxx          0 S /opt/google/chrome
sda1           0      0      0.6   1.0  5381 xxx          0 S /home/xxx/Programs
sdc1           0      0      0.3   0.5  2102 xxx          0 S /opt/google/chrome
                             0.3   0.4  2689 xxx          0 S /opt/google/chrome
FILE SYS    Used  Total      0.3   0.6  4831 xxx          0 S /home/xxx/Programs
/          15.6G   228G
2019-02-13 05:39:04       No warning or critical alert detected