I want to check how many cores my Python script is using.
Suppose that I have this code:
while True: print('Hello World!')When I run top, it gives the CPU, Memory, percentage in addition to other information but not the cores id or how many cores the process is using.
top - 11:44:15 up 1 day, 23:08, 1 user, load average: 2.88, 2.39, 2.15
Tasks: 289 total, 5 running, 238 sleeping, 0 stopped, 0 zombie
%Cpu(s): 55.2 us, 31.8 sy, 0.0 ni, 12.8 id, 0.0 wa, 0.0 hi, 0.2 si, 0.0 st
KiB Mem : 7945496 total, 1027328 free, 4707680 used, 2210488 buff/cache
KiB Swap: 15999996 total, 14991876 free, 1008120 used. 2615420 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
15336 lenovo 20 0 4393044 470488 192616 S 8.6 5.9 148:18.31 firefox 4412 lenovo 20 0 4521092 437940 65416 R 15.6 5.5 87:58.54 gnome-shell 4221 root 20 0 561840 82500 45652 R 9.9 1.0 84:25.21 Xorg
15395 lenovo 20 0 3871472 319376 151876 S 0.0 4.0 83:57.26 Web Content 2838 lenovo 20 0 3993616 823816 158412 R 68.5 10.4 36:28.10 Web Content 4435 lenovo 9 -11 2915368 11596 8836 S 0.3 0.1 35:46.08 pulseaudio 3342 lenovo 20 0 3060860 324000 127948 S 8.6 4.1 27:53.92 atom
29632 lenovo 20 0 3717204 750864 152688 S 10.3 9.5 22:25.05 Web Content
15443 lenovo 20 0 3273020 245772 50128 S 2.3 3.1 19:49.64 WebExtensions 3293 lenovo 20 0 1291576 215972 112612 S 4.6 2.7 15:38.90 atom 3319 lenovo 20 0 734208 226016 104340 S 5.6 2.8 14:52.60 atom 1446 root -51 0 0 0 0 S 1.0 0.0 14:21.71 irq/132-nvidia
16083 lenovo 20 0 446420 35468 27844 S 1.3 0.4 11:06.27 RDD Process
29733 lenovo 20 0 3537988 363160 235184 S 0.0 4.6 9:29.13 Web Content
29780 lenovo 20 0 3414220 363812 174640 S 0.3 4.6 7:50.64 Web Content
29570 lenovo 20 0 3068760 245412 125788 S 0.3 3.1 4:14.76 Web Content 1733 gdm 20 0 3464584 75712 45704 S 0.0 1.0 4:08.74 gnome-shell I did some googling, and I found this command:
watch -tdn0.5 ps -mo pid,tid,%cpu,psr -p \`pgrep python\`Which outputs:
PID TID %CPU PSR
15329 - 95.2 - - 15329 95.2 1Well I am not sure if the previous command really does the trick or not.
If anyone could give an explanation, I would be grateful.
EDIT:
I am using Ubuntu 18.04 the desktop version.
Kernel version :
4.15.0-99-generic #100-Ubuntu SMP Wed Apr 22 20:32:56 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux2 Answers
With top, you can show the "last used CPU":
Fields Management for window 1:Def, whose current sort field is %CPU Navigate with Up/Dn, Right selects for move then <Enter> or Left commits, 'd' or <Space> toggles display, 's' sets sort. Use 'q' or <Esc> to end!
* PID = Process Id SUSER = Saved User Name vMj = Major Faults delta PPID = Parent Process pid GID = Group Id vMn = Minor Faults delta TGID = Thread Group Id GROUP = Group Name USED = Res+Swap Size (KiB)
* USER = Effective User Name PGRP = Process Group Id nsIPC = IPC namespace Inode
* PR = Priority TTY = Controlling Tty nsMNT = MNT namespace Inode
* NI = Nice Value TPGID = Tty Process Grp Id nsNET = NET namespace Inode
* VIRT = Virtual Image (KiB) SID = Session Id nsPID = PID namespace Inode
* RES = Resident Size (KiB) TIME = CPU Time nsUSER = USER namespace Inode SHR = Shared Memory (KiB) SWAP = Swapped Size (KiB) nsUTS = UTS namespace Inode
* %CPU = CPU Usage CODE = Code Size (KiB) LXC = LXC container name
* %MEM = Memory Usage (RES) DATA = Data+Stack (KiB) RSan = RES Anonymous (KiB)
* TIME+ = CPU Time, hundredths nMaj = Major Page Faults RSfd = RES File-based (KiB) nTH = Number of Threads nMin = Minor Page Faults RSlk = RES Locked (KiB) P = Last Used Cpu (SMP) nDRT = Dirty Pages Count RSsh = RES Shared (KiB)
* S = Process Status Flags = Task Flags <sched.h> CGNAME = Control Group name WCHAN = Sleeping in Function CGROUPS = Control Groups NU = Last Used NUMA node
* COMMAND = Command Name/Line SUPGIDS = Supp Groups IDs UID = Effective User Id SUPGRPS = Supp Groups Names RUID = Real User Id OOMa = OOMEM Adjustment RUSER = Real User Name OOMs = OOMEM Score current SUID = Saved User Id ENVIRON = Environment vars Press f, navigate to P (Last Used CPU), press d to mark it for display, and press q to go back to the process view.
To show the threads instead of processes (a process runs on multiple CPUs at once by having its threads scheduled on them), run top with the -H option, or press H after starting it.
Example with Firefox:
top - 03:25:57 up 2:36, 1 user, load average: 0.61, 0.43, 0.45
Threads: 86 total, 0 running, 86 sleeping, 0 stopped, 0 zombie
%Cpu(s): 2.4/1.2 4[||| ]
GiB Mem : 23.7/15.4 [ ]
GiB Swap: 0.0/0.0 [ ] PID USER PR NI VIRT RES %CPU %MEM TIME+ P S COMMAND 3870 muru 20 0 3354.0m 461.1m 2.0 2.9 13:43.39 4 S firefox 3875 muru 20 0 3354.0m 461.1m 0.7 2.9 2:54.10 0 S Gecko_IOThread 4063 muru 20 0 3354.0m 461.1m 0.7 2.9 0:12.78 9 S URL Classifier 3873 muru 20 0 3354.0m 461.1m 0.0 2.9 0:00.00 6 S gmain 3874 muru 20 0 3354.0m 461.1m 0.0 2.9 0:08.25 6 S gdbus 3876 muru 20 0 3354.0m 461.1m 0.0 2.9 0:31.17 1 S Timer 3877 muru 20 0 3354.0m 461.1m 0.0 2.9 0:00.00 8 S Netlink Monitor 3878 muru 20 0 3354.0m 461.1m 0.0 2.9 0:16.99 9 S Socket Thread 3879 muru 20 0 3354.0m 461.1m 0.0 2.9 0:00.43 11 S Permission 3882 muru 20 0 3354.0m 461.1m 0.0 2.9 0:00.25 6 S JS Watchdog 3883 muru 20 0 3354.0m 461.1m 0.0 2.9 0:02.15 11 S JS Helper I found a great tool, similar to top, but with more details.
htop, it can be installed by running sudo apt install htop.
This is the default interface after running htop.
As you can see, there are much more information about the running processes, CPU and memory usage.
Similar to top, it is also possible to add new columns with more information.
In my case, to display on which core the process/thread is running:
- Press F2 (or fn + F2 for some computers).
- Move down to columns section under Setup.
- Press the right arrow key to move to Active Columns, you can move up or down to choose the place where to add the new column.
- Press the right arrow key to move to the Available Columns.
- Move to the column you want to add and press enter once it is selected.
- Once the new column added, press Esc.
Here is a screenshot after I added the new column:
