在 Linux 上检索单个进程的 CPU 使用率和内存使用率？

Question

I want to get the CPU and memory usage of a single process on Linux - I know the PID. Hopefully, I can get it every second and write it to a CSV using the 'watch' command. What command can I use to get this info from the Linux command-line?

Answer 1

ps -p <pid> -o %cpu,%mem,cmd

(You can leave off "cmd" but that might be helpful in debugging).

Note that this gives average CPU usage of the process over the time it has been running.

Answer 2

A variant of caf's answer : top -p <pid>

This auto-refreshes the CPU usage so it's good for monitoring.

Answer 3

You can get the results by the name of the process using

ps -C chrome -o %cpu,%mem,cmd

the -C option allows you to use process name without knowing it's pid.

Answer 4

ps command (should not use):

• CPU usage is currently expressed as the percentage of time spent running during the entire lifetime of a process.

top command (should use):

• The task's share of the elapsed CPU time since the last screen update, expressed as a percentage of total CPU time.

Use top to get CPU usage in real time(current short interval):

top -b -n 2 -d 0.2 -p 6962 | tail -1 | awk '{print $9}'

will echo like: 78.6

• -b : Batch-mode
• -n 2 : Number-of-iterations, use 2 because: When you first run it, it has no previous sample to compare to, so these initial values are the percentages since boot.
• -d 0.2 : Delay-time(in second, here is 200ms)
• -p 6962 : Monitor-PIDs
• tail -1 : the last row
• awk '{print $9}' : the 9-th column(the cpu usage number)

Answer 5

Use pidstat (from sysstat -Refer Link ).

eg to monitor these two process IDs (12345 and 11223) every 5 seconds use

$ pidstat -h -r -u -v -p 12345,11223 5

Answer 6

Launch a program and monitor it

This form is useful if you want to benchmark an executable easily:

topp() (
  $* &>/dev/null &
  pid="$!"
  trap ':' INT
  echo 'CPU  MEM'
  while sleep 1; do ps --no-headers -o '%cpu,%mem' -p "$pid"; done
  kill "$pid"
)
topp ./myprog arg1 arg2

Now when you hit Ctrl + C it exits the program and stops monitoring. Sample output:

CPU  MEM
20.0  1.3
35.0  1.3
40.0  1.3

Related: https://unix.stackexchange.com/questions/554/how-to-monitor-cpu-memory-usage-of-a-single-process

Tested on Ubuntu 16.04.

Answer 7

您可以使用top -b并 grep 输出您想要的 pid（使用-b标志 top 在批处理模式下运行），或者也可以使用-p标志并在不使用 grep 的情况下指定 pid。

Answer 8

As commented in caf's answer above, ps and in some cases pidstat will give you the lifetime average of the pCPU. To get more accurate results use top. If you need to run top once you can run:

top -b -n 1 -p <PID>

or for process only data and header:

top -b -n 1 -p <PID> | tail -3 | head -2

without headers:

top -b -n 1 -p <PID> | tail -2 | head -1

Answer 9

ps aux | awk '{print $4"\t"$11}' | sort | uniq -c | awk '{print $2" "$1" "$3}' | sort -nr

或每个进程

ps aux | awk '{print $4"\t"$11}' | sort | uniq -c | awk '{print $2" "$1" "$3}' | sort -nr |grep mysql

Answer 10

The following command gets the average of CPU and memory usage every 40 seconds for a specific process(pid)

pidstat 40 -ru -p <pid>

Output for my case(first two lines for CPU usage, second two lines for memory):

02:15:07 PM       PID    %usr %system  %guest    %CPU   CPU  Command
02:15:47 PM     24563    0.65    0.07    0.00    0.73     3  java

02:15:07 PM       PID  minflt/s  majflt/s     VSZ    RSS   %MEM  Command
02:15:47 PM     24563      6.95      0.00 13047972 2123268   6.52  java

Answer 11

For those who struggled for a while wonderring why the selected answer does not work:

ps -p <pid> -o %cpu,%mem

No SPACE ibetween %cpu, and %mem .

Answer 12

To get the memory usage of just your application (as opposed to the shared libraries it uses, you need to use the Linux smaps interface). This answer explains it well .

Answer 13

ps aux|awk  '{print $2,$3,$4}'|grep PID

其中第一列是 PID，第二列是 CPU 使用率，第三列是内存使用率。

Answer 14

ps axo pid,etime,%cpu,%mem,cmd | grep 'processname' | grep -v grep

PID - Process ID

etime - Process Running/Live Duration

%cpu - CPU usage

%mem - Memory usage

cmd - Command

Replace processname with whatever process you want to track, mysql nginx php-fpm etc ...

Answer 15

All of the answers here show only the memory percentage for the PID.

Here's an example of how to get the rss memory usage in KB for all apache processes, replace "grep apache" with "grep PID" if you just want to watch a specific PID:

watch -n5 "ps aux -y | grep apache | awk '{print \$2,\$6}'"

This prints:

Every 5.0s: ps aux -y | grep apache | awk '{print $2,$6}'                                                                                                                                                                                                          
Thu Jan 25 15:44:13 2018

12588 9328
12589 8700
12590 9392
12591 9340
12592 8700
12811 15200
15453 9340
15693 3800
15694 2352
15695 1352
15697 948
22896 9360

With CPU %:

watch -n5 "ps aux -y | grep apache | awk '{print \$2,\$3,\$6}'"

Output:

Every 5.0s: ps aux -y | grep apache | awk '{print $2,$3,$6}'                                                                                                                                                                                                       
Thu Jan 25 15:46:00 2018

12588 0.0 9328
12589 0.0 8700
12590 0.0 9392
12591 0.0 9340
12592 0.0 8700
12811 0.0 15200
15453 0.0 9340
15778 0.0 3800
15779 0.0 2352
15780 0.0 1348
15782 0.0 948
22896 0.0 9360

Answer 16

这是一个很好的技巧，可以实时跟踪一个或多个程序，同时观察其他工具的输出： watch "top -bn1 -p$(pidof foo),$(pidof bar); tool"

Answer 17

Based on @caf's answer, this working nicely for me.

Calculate average for given PID:

measure.sh

times=100
total=0
for i in $(seq 1 $times)
do
   OUTPUT=$(top -b -n 1 -d 0.1 -p $1 | tail -1 | awk '{print $9}')
   echo -n "$i time: ${OUTPUT}"\\r
   total=`echo "$total + $OUTPUT" | bc -l`
done
#echo "Average: $total / $times" | bc

average=`echo "scale=2; $total / $times" | bc`
echo "Average: $average"

Usage:

# send PID as argument
sh measure.sh 3282

Answer 18

(If you are in MacOS 10.10, try the accumulative -c option of top:

top -c a -pid PID

(This option is not available in other linux, tried with Scientific Linux el6 and RHEL6)

Answer 19

上面列出了 CPU 和内存消耗最高的进程

        ps axo %cpu,%mem,command | sort -nr | head

Answer 20

根据@Neon 的回答，我的两分钱在这里：

pidstat -h -r -u -v -p $(ps aux | grep <process name> | awk '{print $2}' | tr '\n' ',')

Answer 21

Based on this answer we can estimate the average CPU and memory utilization of a specific process for a specific amount of time by collecting N samples with sampling period T as follows:

N=3;
T=1;
PROCESS_NAME="my_proc";

top -b -c -n $(let tmp=N+1; echo $tmp) -d ${T} -p $(pgrep ${PROCESS_NAME}) | 
grep ${PROCESS_NAME} |  
tee /var/tmp/foo.log |
tail -n +2 | 
awk -v N=$N 'BEGIN{
                c=0; 
                m=0
            }{
                c=c+$9; 
                m=m+$10
            }END{
                printf("%s %s\n", c/N, m/N) 
            }';

In order to be able to evaluate the results we are collecting the output of the top into the /var/tmp/foo.log file. The expected output is something like this:

2.33333 6.9

And the content of our log file:

196918 root      20   0   24.4g   1.3g 113872 S   0.0   6.9  39:58.15 my_proc
196918 root      20   0   24.4g   1.3g 113872 S   2.0   6.9  39:58.17 my_proc
196918 root      20   0   24.4g   1.3g 113872 S   3.0   6.9  39:58.20 my_proc
196918 root      20   0   24.4g   1.3g 113872 S   2.0   6.9  39:58.22 my_proc

Note that we ignore ( tail -n +2 ) the first execution of the top command.

Answer 22

CPU and memory usage of a single process on Linux or you can get the top 10 cpu utilized processes by using below command

ps -aux --sort -pcpu | head -n 11