1. Article purpose[edit source]
This article provides the basic information needed to start using the Linux® tool: top[1].
2. Introduction[edit source]
The following table provides a brief description of the tool, as well as its availability depending on the software packages:
: this tool is either present (ready to use or to be activated), or can be integrated and activated on the software package.
: this tool is not present and cannot be integrated, or it is present but cannot be activated on the software package.
| Tool | STM32MPU Embedded Software distribution | STM32MPU Embedded Softwaredistribution for Android™ | ||||||
|---|---|---|---|---|---|---|---|---|
| Name | Category | Purpose | Starter Package | Developer Package | Distribution Package | Starter Package | Developer Package | Distribution Package |
| top | Monitoring tools | The top[1] program provides a dynamic real-time view of a running system. It can display system summary information as well as a list of tasks currently being managed by the Linux kernel. The types of system summary information shown and the types, order and size of information displayed for tasks are all user configurable and that configuration can be made persistent across restarts. (Extracted from man page[1]) | |
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3. Installing the trace and debug tool on your target board[edit source]
3.1. Using the STM32MPU Embedded Software Distribution[edit source]
top is installed by default and is ready to be used with all STM32MPU Embedded Software Packages.
which top /usr/bin/top
It is integrated into the Weston image distribution by using the following meta-st package recipe to enable the procps module: layers/meta-st/meta-st-openstlinux/recipes-st/packagegroups/packagegroup-framework-tools.bb.
RDEPENDS_packagegroup-framework-tools-core = "\
grep \
util-linux \
util-linux-lscpu \
procps \
kbd \
...
3.2. Using the STM32MPU Embedded Software distribution for Android™[edit source]
top is installed by default and ready to be used with all STM32MPU Embedded Software Packages for Android™.
It comes with the toybox:
which top | xargs ls -la /system/bin/top -> toybox
4. Getting started[edit source]
- Displaying individual threads: without this command-line option a summation of all threads in each process is shown
top -H top - 16:50:23 up 4:31, 1 user, load average: 0.38, 0.38, 0.37 Threads: 130 total, 1 running, 129 sleeping, 0 stopped, 0 zombie %Cpu(s): 4.3 us, 10.9 sy, 0.0 ni, 84.8 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st MiB Mem : 871.9 total, 673.1 free, 107.7 used, 91.2 buff/cache MiB Swap: 0.0 total, 0.0 free, 0.0 used. 736.6 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 895 root 20 0 2652 1608 1220 R 25.0 0.2 0:00.08 top 1 root 20 0 24164 4808 3104 S 0.0 0.5 0:17.88 systemd 2 root 20 0 0 0 0 S 0.0 0.0 0:00.03 kthreadd 3 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 rcu_gp 4 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 rcu_par_gp 6 root 0 -20 0 0 0 I 0.0 0.0 0:00.01 kworker/0:0H-kblockd 7 root 20 0 0 0 0 I 0.0 0.0 0:00.04 kworker/u4:0-events_unbound 8 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 mm_percpu_wq 9 root 20 0 0 0 0 S 0.0 0.0 0:01.42 ksoftirqd/0 10 root 20 0 0 0 0 I 0.0 0.0 0:03.19 rcu_preempt 11 root 20 0 0 0 0 I 0.0 0.0 0:00.00 rcu_sched 12 root 20 0 0 0 0 I 0.0 0.0 0:00.00 rcu_bh 13 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/0 14 root 20 0 0 0 0 S 0.0 0.0 0:00.00 cpuhp/0 15 root 20 0 0 0 0 S 0.0 0.0 0:00.00 cpuhp/1 16 root rt 0 0 0 0 S 0.0 0.0 0:00.00 migration/1 17 root 20 0 0 0 0 S 0.0 0.0 0:01.64 ksoftirqd/1 19 root 0 -20 0 0 0 I 0.0 0.0 0:00.07 kworker/1:0H-kblockd 20 root 20 0 0 0 0 S 0.0 0.0 0:00.04 kdevtmpfs 21 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 netns 22 root 20 0 0 0 0 S 0.0 0.0 0:00.00 rcu_tasks_kthre 24 root 20 0 0 0 0 S 0.0 0.0 0:00.00 oom_reaper 25 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 writeback 26 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kcompactd0 27 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 crypto 28 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kblockd 29 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 ata_sff 30 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 edac-poller 31 root rt 0 0 0 0 S 0.0 0.0 0:00.00 watchdogd 32 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 rpciod 33 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 kworker/u5:0 34 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 xprtiod 35 root 20 0 0 0 0 S 0.0 0.0 0:00.00 kswapd0 36 root 0 -20 0 0 0 I 0.0 0.0 0:00.00 nfsiod
- Displaying only given PID:
top -p<PID>
<PID> can be a given known value, or it could be useful to use the pidof macro:
top -p`pidof netdata`
top - 16:59:39 up 4:40, 1 user, load average: 0.46, 0.46, 0.41
Tasks: 1 total, 0 running, 1 sleeping, 0 stopped, 0 zombie
%Cpu(s): 0.0 us, 2.9 sy, 0.0 ni, 97.1 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
MiB Mem : 871.9 total, 673.2 free, 107.6 used, 91.2 buff/cache
MiB Swap: 0.0 total, 0.0 free, 0.0 used. 736.6 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
389 root 20 0 131340 15528 2036 S 0.0 1.7 2:39.63 netdata
and by adding -H option:
top -p`pidof netdata` -H
top - 16:58:15 up 4:39, 1 user, load average: 0.62, 0.48, 0.41
Threads: 12 total, 0 running, 12 sleeping, 0 stopped, 0 zombie
%Cpu(s): 0.3 us, 0.5 sy, 0.0 ni, 99.2 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st
MiB Mem : 871.9 total, 673.1 free, 107.6 used, 91.2 buff/cache
MiB Swap: 0.0 total, 0.0 free, 0.0 used. 736.6 avail Mem
PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND
407 root 20 0 131340 15528 2036 S 0.3 1.7 1:06.85 netdata
409 root 20 0 131340 15528 2036 S 0.3 1.7 0:46.08 netdata
389 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.23 netdata
406 root 20 0 131340 15528 2036 S 0.0 1.7 0:13.30 netdata
408 root 20 0 131340 15528 2036 S 0.0 1.7 0:05.31 netdata
411 root 20 0 131340 15528 2036 S 0.0 1.7 0:03.51 netdata
412 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.09 netdata
413 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.08 netdata
414 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.92 netdata
418 root 20 0 131340 15528 2036 S 0.0 1.7 0:01.24 netdata
419 root 20 0 131340 15528 2036 S 0.0 1.7 0:21.12 netdata
425 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.00 netdata
Note that several PIDs can be given by using the following syntax:
top -p<PID1>,<PID2>,<PID3>...
- Sorting informations
When the top command result is displayed, type "F", then select a filter: please see highlighted part below:
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 SUPGRPS = Supp Groups Names * USER = Effective User Name TGID = Thread Group Id * PR = Priority OOMa = OOMEM Adjustment * NI = Nice Value OOMs = OOMEM Score current * VIRT = Virtual Image (KiB) ENVIRON = Environment vars * RES = Resident Size (KiB) vMj = Major Faults delta * SHR = Shared Memory (KiB) vMn = Minor Faults delta * S = Process Status USED = Res+Swap Size (KiB) * %CPU = CPU Usage nsIPC = IPC namespace Inode * %MEM = Memory Usage (RES) nsMNT = MNT namespace Inode * TIME+ = CPU Time, hundredths nsNET = NET namespace Inode * COMMAND = Command Name/Line nsPID = PID namespace Inode PPID = Parent Process pid nsUSER = USER namespace Inode UID = Effective User Id nsUTS = UTS namespace Inode RUID = Real User Id LXC = LXC container name RUSER = Real User Name RSan = RES Anonymous (KiB) SUID = Saved User Id RSfd = RES File-based (KiB) SUSER = Saved User Name RSlk = RES Locked (KiB) GID = Group Id RSsh = RES Shared (KiB) GROUP = Group Name CGNAME = Control Group name PGRP = Process Group Id NU = Last Used NUMA node TTY = Controlling Tty TPGID = Tty Process Grp Id SID = Session Id nTH = Number of Threads P = Last Used Cpu (SMP) TIME = CPU Time SWAP = Swapped Size (KiB) CODE = Code Size (KiB) DATA = Data+Stack (KiB) nMaj = Major Page Faults nMin = Minor Page Faults nDRT = Dirty Pages Count WCHAN = Sleeping in Function Flags = Task Flags <sched.h> CGROUPS = Control Groups SUPGIDS = Supp Groups IDs
- Displaying where threads are sleeping
When the top command result is displayed, type "F", then go to the WCHAN parameter. Type "d" or <space> to toggle the display of this field.
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 SUPGRPS = Supp Groups Names * USER = Effective User Name TGID = Thread Group Id * PR = Priority OOMa = OOMEM Adjustment * NI = Nice Value OOMs = OOMEM Score current * VIRT = Virtual Image (KiB) ENVIRON = Environment vars * RES = Resident Size (KiB) vMj = Major Faults delta * SHR = Shared Memory (KiB) vMn = Minor Faults delta * S = Process Status USED = Res+Swap Size (KiB) * %CPU = CPU Usage nsIPC = IPC namespace Inode * %MEM = Memory Usage (RES) nsMNT = MNT namespace Inode * TIME+ = CPU Time, hundredths nsNET = NET namespace Inode * COMMAND = Command Name/Line nsPID = PID namespace Inode PPID = Parent Process pid nsUSER = USER namespace Inode UID = Effective User Id nsUTS = UTS namespace Inode RUID = Real User Id LXC = LXC container name RUSER = Real User Name RSan = RES Anonymous (KiB) SUID = Saved User Id RSfd = RES File-based (KiB) SUSER = Saved User Name RSlk = RES Locked (KiB) GID = Group Id RSsh = RES Shared (KiB) GROUP = Group Name CGNAME = Control Group name PGRP = Process Group Id NU = Last Used NUMA node TTY = Controlling Tty TPGID = Tty Process Grp Id SID = Session Id nTH = Number of Threads P = Last Used Cpu (SMP) TIME = CPU Time SWAP = Swapped Size (KiB) CODE = Code Size (KiB) DATA = Data+Stack (KiB) nMaj = Major Page Faults nMin = Minor Page Faults nDRT = Dirty Pages Count * WCHAN = Sleeping in Function Flags = Task Flags <sched.h> CGROUPS = Control Groups SUPGIDS = Supp Groups IDs
This option enables the display of wchan.
top -p `pidof netdata`,`pidof python3` top - 17:19:15 up 5:00, 1 user, load average: 0.47, 0.45, 0.45 Tasks: 2 total, 0 running, 2 sleeping, 0 stopped, 0 zombie %Cpu(s): 0.3 us, 1.0 sy, 0.0 ni, 98.7 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st MiB Mem : 871.9 total, 672.9 free, 107.8 used, 91.2 buff/cache MiB Swap: 0.0 total, 0.0 free, 0.0 used. 736.4 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND WCHAN 389 root 20 0 131340 15528 2036 S 0.7 1.7 2:50.72 netdata sys_pause 424 root 20 0 43496 14860 5680 S 0.0 1.7 0:33.02 python3 poll_sche+
- Showing only one iteration of top and putting it in batch mode (useful for putting in a file)
top -p`pidof netdata` -H -b -n1 top - 17:26:53 up 5:07, 1 user, load average: 0.46, 0.47, 0.45 Threads: 12 total, 0 running, 12 sleeping, 0 stopped, 0 zombie %Cpu(s): 0.0 us, 2.9 sy, 0.0 ni, 97.1 id, 0.0 wa, 0.0 hi, 0.0 si, 0.0 st MiB Mem : 871.9 total, 672.9 free, 107.8 used, 91.2 buff/cache MiB Swap: 0.0 total, 0.0 free, 0.0 used. 736.5 avail Mem PID USER PR NI VIRT RES SHR S %CPU %MEM TIME+ COMMAND 389 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.23 netdata 406 root 20 0 131340 15528 2036 S 0.0 1.7 0:14.67 netdata 407 root 20 0 131340 15528 2036 S 0.0 1.7 1:13.64 netdata 408 root 20 0 131340 15528 2036 S 0.0 1.7 0:05.83 netdata 409 root 20 0 131340 15528 2036 S 0.0 1.7 0:50.85 netdata 411 root 20 0 131340 15528 2036 S 0.0 1.7 0:03.92 netdata 412 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.10 netdata 413 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.09 netdata 414 root 20 0 131340 15528 2036 S 0.0 1.7 0:01.00 netdata 418 root 20 0 131340 15528 2036 S 0.0 1.7 0:01.38 netdata 419 root 20 0 131340 15528 2036 S 0.0 1.7 0:23.24 netdata 425 root 20 0 131340 15528 2036 S 0.0 1.7 0:00.00 netdata
5. References[edit source]