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--- top [2012/03/21 10:48]
k2patel created
+++ top [2020/08/10 02:35] (current)
@@ Line 1: / Line 1: @@
 ====== TOP ======
 command to help understanding system performance.
+==== Block on Top ====
 <code bash | Cpu(s) Row>
@@ Line 9: / Line 12: @@
 id = idle
 hi = hardware interrupts
 si = software interrupts
+st = steal time (time in involuntary wait by virtual cpu while hypervisor is servicing another processor)
+</code>
+==== Columns ====
+Listed below are top's available fields. They are always associated with the letter shown, \\
+regardless of the position you may have established for them with the 'o' (Order fields) interactive command.
+Any field is selectable as the sort field, and you control whether they are sorted high-to-low or low-to-high.\\
+For additional information on sort provisions see topic 3c. TASK Area Commands.
+<code text | Fields >
+a: PID -- Process Id
+    The task's unique process ID, which periodically wraps, though never restarting at zero.
+b: PPID -- Parent Process Pid
+    The process ID of a task's parent.
+c: RUSER -- Real User Name
+    The real user name of the task's owner.
+d: UID -- User Id
+    The effective user ID of the task's owner.
+e: USER -- User Name
+    The effective user name of the task's owner.
+f: GROUP -- Group Name
+    The effective group name of the task's owner.
+g: TTY -- Controlling Tty
+    The name of the controlling terminal. This is usually the device (serial port, pty, etc.)
+    from which the process was started, and which it uses for input or output.
+    However, a task need not be associated with a terminal, in which case you'll see '?' displayed.
+h: PR -- Priority
+    The priority of the task.
+i: NI -- Nice value
+    The nice value of the task. A negative nice value means higher priority,
+    whereas a positive nice value means lower priority.
+    Zero in this field simply means priority will not be adjusted in determining a task's dispatchability.
+j: P -- Last used CPU (SMP)
+    A number representing the last used processor.
+    In a true SMP environment this will likely change frequently since the kernel intentionally uses weak affinity.
+    Also, the very act of running top may break this weak affinity and cause more processes to change
+    CPUs more often (because of the extra demand for cpu time).
+k: %CPU -- CPU usage
+    The task's share of the elapsed CPU time since the last screen update,
+    expressed as a percentage of total CPU time. In a true SMP environment,
+    if 'Irix mode' is Off, top will operate in 'Solaris mode' where a task's cpu usage will be divided by the total number of CPUs.
+    You toggle 'Irix/Solaris' modes with the 'I' interactive command.
+l: TIME -- CPU Time
+    Total CPU time the task has used since it started. When 'Cumulative mode' is On,
+    each process is listed with the cpu time that it and its dead children has used.
+    You toggle 'Cumulative mode' with 'S', which is a command-line option and an interactive command.
+    See the 'S' interactive command for additional information regarding this mode.
+m: TIME+ -- CPU Time, hundredths
+    The same as 'TIME', but reflecting more granularity through hundredths of a second.
+n: %MEM -- Memory usage (RES)
+    A task's currently used share of available physical memory.
+o: VIRT -- Virtual Image (kb)
+    The total amount of virtual memory used by the task.
+    It includes all code, data and shared libraries plus pages that have been swapped out.
+    (Note: you can define the STATSIZE=1 environment variable and the VIRT will be calculated from the /proc/#/state VmSize field.)
+    VIRT = SWAP + RES.
+p: SWAP -- Swapped size (kb)
+    The swapped out portion of a task's total virtual memory image.
+q: RES -- Resident size (kb)
+    The non-swapped physical memory a task has used.
+    RES = CODE + DATA.
+r: CODE -- Code size (kb)
+    The amount of physical memory devoted to executable code, also known as the 'text resident set' size or TRS.
+s: DATA -- Data+Stack size (kb)
+    The amount of physical memory devoted to other than executable code, also known as the 'data resident set' size or DRS.
+t: SHR -- Shared Mem size (kb)
+    The amount of shared memory used by a task. It simply reflects memory that could be potentially shared with other processes.
+u: nFLT -- Page Fault count
+    The number of major page faults that have occurred for a task.
+    A page fault occurs when a process attempts to read from or write to a virtual page that is not currently present in its address space.
+    A major page fault is when disk access is involved in making that page available.
+v: nDRT -- Dirty Pages count
+    The number of pages that have been modified since they were last written to disk.
+    Dirty pages must be written to disk before the corresponding physical memory location can be used for some other virtual page.
+w: S -- Process Status
+    The status of the task which can be one of: 'D' = uninterruptible sleep 'R' = running 'S' = sleeping 'T' = traced or stopped 'Z' = zombie
+    Tasks shown as running should be more properly thought of as 'ready to run' -- their task_struct is simply represented on the Linux run-queue.
+    Even without a true SMP machine, you may see numerous tasks in this state depending on top's delay interval and nice value.
+x: Command -- Command line or Program name
+    Display the command line used to start a task or the name of the associated program.
+    You toggle between command line and name with 'c', which is both a command-line option and an interactive command.
+    When you've chosen to display command lines,
+    processes without a command line (like kernel threads) will be shown with only the program name in parentheses,
+    as in this example: ( mdrecoveryd )
+    Either form of display is subject to potential truncation if it's too long to fit in this field's current width.
+    That width depends upon other fields selected, their order and the current screen width.
+    Note: The 'Command' field/column is unique, in that it is not fixed-width.
+    When displayed, this column will be allocated all remaining screen width
+    (up to the maximum 512 characters) to provide for the potential growth of program names into command lines.
+y: WCHAN -- Sleeping in Function
+    Depending on the availability of the kernel link map ('System.map'),
+    this field will show the name or the address of the kernel function in which the task is currently sleeping.
+    Running tasks will display a dash ('-') in this column.
+    Note: By displaying this field, top's own working set will be increased by over 700Kb.
+    Your only means of reducing that overhead will be to stop and restart top.
+z: Flags -- Task Flags
+    This column represents the task's current scheduling flags which are expressed in hexadecimal notation and with zeros suppressed.
+    These flags are officially documented in <linux/sched.h>.
+    Less formal documentation can also be found on the 'Fields select' and 'Order fields' screens.
+</code>
+==== .toprc ====
+.toprc is the file you do not need to play with it all the time.\\
+Here is my .toprc file.\\
+<code bash | ~/.toprc>
+RCfile for "top with windows"           # shameless braggin'
+Id:a, Mode_altscr=0, Mode_irixps=1, Delay_time=3.000, Curwin=0
+Def     fieldscur=OQNTKPMehaiWbcdfgJlrsuvyzX
+        winflags=130489, sortindx=13, maxtasks=0
+        summclr=6, msgsclr=1, headclr=3, taskclr=2
+Job     fieldscur=ABcefgjlrstuvyzMKNHIWOPQDX
+        winflags=64825, sortindx=0, maxtasks=0
+        summclr=6, msgsclr=6, headclr=7, taskclr=6
+Mem     fieldscur=ANOPQRSTUVbcdefgjlmyzWHIKX
+        winflags=64825, sortindx=13, maxtasks=0
+        summclr=5, msgsclr=5, headclr=4, taskclr=5
+Usr     fieldscur=ABDECGfhijlopqrstuvyzMKNWX
+        winflags=64825, sortindx=4, maxtasks=0
+        summclr=3, msgsclr=3, headclr=2, taskclr=3
+</code>
+Playing with color is not advised from interface as it was hard for me :) still you can try using "Z"\\
+Here is how i played.
+<code text>
+Select target as upper case letter:
+   S = Summary Data,  M = Messages/Prompts,
+   H = Column Heads,  T = Task Information
+Select color as number:
+= black,  1 = red,      2 = green,  3 = yellow,
+= blue,   5 = magenta,  6 = cyan,   7 = white
 </code>
+**Curwin=0** Which define which block you are using start the first one as "0".
+**summclr=6, msgsclr=1, headclr=3, taskclr=2** this is the value you can play with with above list of colors.

Daily *Nix

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