pcp-atop(1)
NAME
pcp-atop, pmatop - Advanced System and Process Monitor
SYNOPSIS
Interactive Usage: pcp [pcp options] atop [-g|-m|-d|-n|-u|-p|-s|-c|-v|-o|-y] [-C|-M|-D|-N|-A] [-afFG1xR] [-L linelen] [-Plabel[,label]...] [interval [samples]] Writing and reading raw logfiles: pcp atop -w rawfile [-a] [-S] [interval [samples]] pcp atop -r [ rawfile ] [-b hh:mm ] [-e hh:mm ] [-g|-m|-d|-n|-u|-p|-s|-c|-v|-o|-y] [-C|-M|-D|-N|-A] [-fFG1xR] [-L linelen] [-Plabel[,label]...]
DESCRIPTION
The program pcp-atop is an interactive monitor to view various aspects of load on a system. It shows the occupation of the most critical hardware resources (from a performance point of view) on system level, i.e. cpu, memory, disk and network. It also shows which processes are responsible for the indicated load with respect to cpu and memory load on process level. Disk load is shown per process if "storage accounting" is active in the kernel. Every interval (default: 10 seconds) information is shown about the resource occupation on system level (cpu, memory, disks and network layers), followed by a list of processes which have been active during the last interval (note that all processes that were unchanged during the last interval are not shown, unless the key 'a' has been pressed). If the list of active processes does not entirely fit on the screen, only the top of the list is shown (sorted in order of activity). The intervals are repeated till the number of samples (specified as command argument) is reached, or till the key 'q' is pressed in interactive mode. When invoked via the pcp(1) command, the PCPIntro(1) options -h/--host, -a/--archive, -O/--origin, -s/--samples, -t/--interval, -Z/--timezone and several other pcp options become indirectly available. When pcp-atop is started, it checks whether the standard output channel is connected to a screen, or to a file/pipe. In the first case it produces screen control codes (via the ncurses library) and behaves interactively; in the second case it produces flat ASCII-output. In interactive mode, the output of pcp-atop scales dynamically to the current dimensions of the screen/window. If the window is resized horizontally, columns will be added or removed automatically. For this purpose, every column has a particular weight. The columns with the highest weights that fit within the current width will be shown. If the window is resized vertically, lines of the process/thread list will be added or removed automatically. Furthermore in interactive mode the output of pcp-atop can be controlled by pressing particular keys. However it is also possible to specify such key as flag on the command line. In that case pcp-atop switches to the indicated mode on beforehand; this mode can be modified again interactively. Specifying such key as flag is especially useful when running pcp-atop with output to a pipe or file (non- interactively). These flags are the same as the keys that can be pressed in interactive mode (see section INTERACTIVE COMMANDS). Additional flags are available to support storage of pcp-atop data in PCP archive format (see section PCP DATA STORAGE).
COLORS
For the resource consumption on system level, pcp-atop uses colors to
indicate that a critical occupation percentage has been (almost)
reached. A critical occupation percentage means that is likely that
this load causes a noticeable negative performance influence for
applications using this resource. The critical percentage depends on
the type of resource: e.g. the performance influence of a disk with a
busy percentage of 80% might be more noticeable for applications/user
than a CPU with a busy percentage of 90%.
Currently pcp-atop uses the following default values to calculate a
weighted percentage per resource:
Processor
A busy percentage of 90% or higher is considered `critical'.
Disk
A busy percentage of 70% or higher is considered `critical'.
Network
A busy percentage of 90% or higher for the load of an interface is
considered `critical'.
Memory
An occupation percentage of 90% is considered `critical'. Notice
that this occupation percentage is the accumulated memory
consumption of the kernel (including slab) and all processes; the
memory for the page cache (`cache' and `buff' in the MEM-line) and
the reclaimable part of the slab (`slrec`) is not implied!
If the number of pages swapped out (`swout' in the PAG-line) is
larger than 10 per second, the memory resource is considered
`critical'. A value of at least 1 per second is considered
`almost critical'.
If the committed virtual memory exceeds the limit (`vmcom' and
`vmlim' in the SWP-line), the SWP-line is colored due to
overcommitting the system.
Swap
An occupation percentage of 80% is considered `critical' because
swap space might be completely exhausted in the near future; it is
not critical from a performance point-of-view.
These default values can be modified in the configuration file (see
separate man-page of pcp-atoprc).
When a resource exceeds its critical occupation percentage, the
concerning values in the screen line are colored red by default.
When a resource exceeded (default) 80% of its critical percentage (so
it is almost critical), the concerning values in the screen line are
colored cyan by default. This `almost critical percentage' (one value
for all resources) can be modified in the configuration file (see
separate man-page of pcp-atoprc).
The default colors red and cyan can be modified in the configuration
file as well (see separate man-page of pcp-atoprc).
With the key 'x' (or flag -x), the use of colors can be suppressed.
INTERACTIVE COMMANDS
When running pcp-atop interactively (no output redirection), keys can
be pressed to control the output. In general, lower case keys can be
used to show other information for the active processes and upper case
keys can be used to influence the sort order of the active
process/thread list.
g Show generic output (default).
Per process the following fields are shown in case of a window-
width of 80 positions: process-id, cpu consumption during the last
interval in system and user mode, the virtual and resident memory
growth of the process.
The subsequent columns depend on the used kernel:
When the kernel supports "storage accounting" (>= 2.6.20), the
data transfer for read/write on disk, the status and exit code are
shown for each process. When the kernel does not support "storage
accounting", the username, number of threads in the thread group,
the status and exit code are shown.
The last columns contain the state, the occupation percentage for
the chosen resource (default: cpu) and the process name.
When more than 80 positions are available, other information is
added.
m Show memory related output.
Per process the following fields are shown in case of a window-
width of 80 positions: process-id, minor and major memory faults,
size of virtual shared text, total virtual process size, total
resident process size, virtual and resident growth during last
interval, memory occupation percentage and process name.
When more than 80 positions are available, other information is
added.
d Show disk-related output.
When "storage accounting" is active in the kernel, the following
fields are shown: process-id, amount of data read from disk,
amount of data written to disk, amount of data that was written
but has been withdrawn again (WCANCL), disk occupation percentage
and process name.
s Show scheduling characteristics.
Per process the following fields are shown in case of a window-
width of 80 positions: process-id, number of threads in state
'running' (R), number of threads in state 'interruptible sleeping'
(S), number of threads in state 'uninterruptible sleeping' (D),
scheduling policy (normal timesharing, realtime round-robin,
realtime fifo), nice value, priority, realtime priority, current
processor, status, exit code, state, the occupation percentage for
the chosen resource and the process name.
When more than 80 positions are available, other information is
added.
v Show various process characteristics.
Per process the following fields are shown in case of a window-
width of 80 positions: process-id, user name and group, start date
and time, status (e.g. exit code if the process has finished),
state, the occupation percentage for the chosen resource and the
process name.
When more than 80 positions are available, other information is
added.
c Show the command line of the process.
Per process the following fields are shown: process-id, the
occupation percentage for the chosen resource and the command line
including arguments.
o Show the user-defined line of the process.
In the configuration file the keyword ownprocline can be specified
with the description of a user-defined output-line.
Refer to the man-page of pcp-atoprc for a detailed description.
y Show the individual threads within a process (toggle).
Single-threaded processes are still shown as one line.
For multi-threaded processes, one line represents the process
while additional lines show the activity per individual thread (in
a different color). Depending on the option 'a' (all or active
toggle), all threads are shown or only the threads that were
active during the last interval.
Whether this key is active or not can be seen in the header line.
u Show the process activity accumulated per user.
Per user the following fields are shown: number of processes
active or terminated during last interval (or in total if combined
with command `a'), accumulated cpu consumption during last
interval in system and user mode, the current virtual and resident
memory space consumed by active processes (or all processes of the
user if combined with command `a').
When "storage accounting" is active in the kernel, the accumulated
read and write throughput on disk is shown. When the kernel
module `netatop' has been installed, the number of received and
sent network packets are shown.
The last columns contain the accumulated occupation percentage for
the chosen resource (default: cpu) and the user name.
p Show the process activity accumulated per program (i.e. process
name).
Per program the following fields are shown: number of processes
active or terminated during last interval (or in total if combined
with command `a'), accumulated cpu consumption during last
interval in system and user mode, the current virtual and resident
memory space consumed by active processes (or all processes of the
user if combined with command `a').
When "storage accounting" is active in the kernel, the accumulated
read and write throughput on disk is shown. When the kernel
module `netatop' has been installed, the number of received and
sent network packets are shown.
The last columns contain the accumulated occupation percentage for
the chosen resource (default: cpu) and the program name.
C Sort the current list in the order of cpu consumption (default).
The one-but-last column changes to ``CPU''.
M Sort the current list in the order of resident memory consumption.
The one-but-last column changes to ``MEM''.
D Sort the current list in the order of disk accesses issued. The
one-but-last column changes to ``DSK''.
N Sort the current list in the order of network bandwidth (received
and transmitted). The one-but-last column changes to ``NET''.
A Sort the current list automatically in the order of the most busy
system resource during this interval. The one-but-last column
shows either ``ACPU'', ``AMEM'', ``ADSK'' or ``ANET'' (the
preceding 'A' indicates automatic sorting-order). The most busy
resource is determined by comparing the weighted busy-percentages
of the system resources, as described earlier in the section
COLORS.
This option remains valid until another sorting-order is
explicitly selected again.
A sorting-order for disk is only possible when "storage
accounting" is active. A sorting-order for network is only
possible when the kernel module `netatop' is loaded.
Miscellaneous interactive commands:
? Request for help information (also the key 'h' can be pressed).
V Request for version information (version number and date).
R Gather and calculate the proportional set size of processes
(toggle). Gathering of all values that are needed to calculate
the PSIZE of a process is a relatively time-consuming task, so
this key should only be active when analyzing the resident memory
consumption of processes.
x Suppress colors to highlight critical resources (toggle).
Whether this key is active or not can be seen in the header line.
z The pause key can be used to freeze the current situation in order
to investigate the output on the screen. While pcp-atop is paused,
the keys described above can be pressed to show other information
about the current list of processes. Whenever the pause key is
pressed again, pcp-atop will continue with a next sample.
i Modify the interval timer (default: 10 seconds). If an interval
timer of 0 is entered, the interval timer is switched off. In that
case a new sample can only be triggered manually by pressing the
key 't'.
t Trigger a new sample manually. This key can be pressed if the
current sample should be finished before the timer has exceeded,
or if no timer is set at all (interval timer defined as 0). In the
latter case pcp-atop can be used as a stopwatch to measure the
load being caused by a particular application transaction, without
knowing on beforehand how many seconds this transaction will last.
When viewing the contents of a raw file, this key can be used to
show the next sample from the file.
T When viewing the contents of a raw file, this key can be used to
show the previous sample from the file.
b When viewing the contents of a raw file, this key can be used to
branch to a certain timestamp within the file (either forward or
backward).
r Reset all counters to zero to see the system and process activity
since boot again.
When viewing the contents of a raw file, this key can be used to
rewind to the beginning of the file again.
U Specify a search string for specific user names as a regular
expression. From now on, only (active) processes will be shown
from a user which matches the regular expression. The system
statistics are still system wide. If the Enter-key is pressed
without specifying a name, (active) processes of all users will be
shown again.
Whether this key is active or not can be seen in the header line.
I Specify a list with one or more PIDs to be selected. From now on,
only processes will be shown with a PID which matches one of the
given list. The system statistics are still system wide. If the
Enter-key is pressed without specifying a PID, all (active)
processes will be shown again.
Whether this key is active or not can be seen in the header line.
P Specify a search string for specific process names as a regular
expression. From now on, only processes will be shown with a name
which matches the regular expression. The system statistics are
still system wide. If the Enter-key is pressed without specifying
a name, all (active) processes will be shown again.
Whether this key is active or not can be seen in the header line.
/ Specify a specific command line search string as a regular
expression. From now on, only processes will be shown with a
command line which matches the regular expression. The system
statistics are still system wide. If the Enter-key is pressed
without specifying a string, all (active) processes will be shown
again.
Whether this key is active or not can be seen in the header line.
S Specify search strings for specific logical volume names, specific
disk names and specific network interface names. All search
strings are interpreted as a regular expressions. From now on,
only those system resources are shown that match the concerning
regular expression. If the Enter-key is pressed without
specifying a search string, all (active) system resources of that
type will be shown again.
Whether this key is active or not can be seen in the header line.
a The `all/active' key can be used to toggle between only
showing/accumulating the processes that were active during the
last interval (default) or showing/accumulating all processes.
Whether this key is active or not can be seen in the header line.
G By default, pcp-atop shows/accumulates the processes that are
alive and the processes that are exited during the last interval.
With this key (toggle), showing/accumulating the processes that
are exited can be suppressed.
Whether this key is active or not can be seen in the header line.
f Show a fixed (maximum) number of header lines for system resources
(toggle). By default only the lines are shown about system
resources (CPUs, paging, logical volumes, disks, network
interfaces) that really have been active during the last interval.
With this key you can force pcp-atop to show lines of inactive
resources as well.
Whether this key is active or not can be seen in the header line.
F Suppress sorting of system resources (toggle). By default system
resources (CPUs, logical volumes, disks, network interfaces) are
sorted on utilization.
Whether this key is active or not can be seen in the header line.
1 Show relevant counters as an average per second (in the format
`..../s') instead of as a total during the interval (toggle).
Whether this key is active or not can be seen in the header line.
l Limit the number of system level lines for the counters per-cpu,
the active disks and the network interfaces. By default lines are
shown of all CPUs, disks and network interfaces which have been
active during the last interval. Limiting these lines can be
useful on systems with huge number CPUs, disks or interfaces in
order to be able to run pcp-atop on a screen/window with e.g. only
24 lines.
For all mentioned resources the maximum number of lines can be
specified interactively. When using the flag -l the maximum number
of per-cpu lines is set to 0, the maximum number of disk lines to
5 and the maximum number of interface lines to 3. These values
can be modified again in interactive mode.
k Send a signal to an active process (a.k.a. kill a process).
q Quit the program.
PgDn Show the next page of the process/thread list.
With the arrow-down key the list can be scrolled downwards with
single lines.
^F Show the next page of the process/thread list (forward).
With the arrow-down key the list can be scrolled downwards with
single lines.
PgUp Show the previous page of the process/thread list.
With the arrow-up key the list can be scrolled upwards with single
lines.
^B Show the previous page of the process/thread list (backward).
With the arrow-up key the list can be scrolled upwards with single
lines.
^L Redraw the screen.
PCP DATA STORAGE
In order to store system and process level statistics for long-term analysis (e.g. to check the system load and the active processes running yesterday between 3:00 and 4:00 PM), pcp-atop can store the system and process level statistics in the PCP archive format, as an archive folio (see mkaf(1)). By default only processes which have been active during the interval are stored in the raw file. When the flag -a is specified, all processes will be stored. The interval (default: 10 seconds) and number of samples (default: infinite) can be passed as last arguments. Instead of the number of samples, the flag -S can be used to indicate that pcp-atop should finish anyhow before midnight. A PCP archive can be read and visualized again with the flag -r . The argument is a comma-separated list of names, each of which may be the base name of an archive or the name of a directory containing one or more archives. If no argument is specified, the file $PCP_LOG_DIR/pmlogger/HOST/YYYYMMDD is opened for input (where YYYYMMDD are digits representing the current date, and HOST is the hostname of the machine being logged). If a filename is specified in the format YYYYMMDD (representing any valid date), the file $PCP_LOG_DIR/pmlogger/HOST/YYYYMMDD is opened. If a filename with the symbolic name y is specified, yesterday's daily logfile is opened (this can be repeated so 'yyyy' indicates the logfile of four days ago). The samples from the file can be viewed interactively by using the key 't' to show the next sample, the key 'T' to show the previous sample, the key 'b' to branch to a particular time or the key 'r' to rewind to the begin of the file. When output is redirected to a file or pipe, pcp-atop prints all samples in plain ASCII. The default line length is 80 characters in that case; with the flag -L followed by an alternate line length, more (or less) columns will be shown. With the flag -b (begin time) and/or -e (end time) followed by a time argument of the form HH:MM, a certain time period within the raw file can be selected.
OUTPUT DESCRIPTION
The first sample shows the system level activity since boot (the elapsed time in the header shows the time since boot). Note that particular counters could have reached their maximum value (several times) and started by zero again, so do not rely on these figures. For every sample pcp-atop first shows the lines related to system level activity. If a particular system resource has not been used during the interval, the entire line related to this resource is suppressed. So the number of system level lines may vary for each sample. After that a list is shown of processes which have been active during the last interval. This list is by default sorted on cpu consumption, but this order can be changed by the keys which are previously described. If values have to be shown by pcp-atop which do not fit in the column width, another format is used. If e.g. a cpu-consumption of 233216 milliseconds should be shown in a column width of 4 positions, it is shown as `233s' (in seconds). For large memory figures, another unit is chosen if the value does not fit (Mb instead of Kb, Gb instead of Mb, Tb instead of Gb, ...). For other values, a kind of exponent notation is used (value 123456789 shown in a column of 5 positions gives 123e6).
OUTPUT DESCRIPTION - SYSTEM LEVEL
The system level information consists of the following output lines:
PRC Process and thread level totals.
This line contains the total cpu time consumed in system mode
(`sys') and in user mode (`user'), the total number of processes
present at this moment (`#proc'), the total number of threads
present at this moment in state `running' (`#trun'), `sleeping
interruptible' (`#tslpi') and `sleeping uninterruptible'
(`#tslpu'), the number of zombie processes (`#zombie'), the number
of clone system calls (`clones'), and the number of processes that
ended during the interval (`#exit') when process accounting is
used. Instead of `#exit` the last column may indicate that process
accounting could not be activated (`no procacct`).
If the screen-width does not allow all of these counters, only a
relevant subset is shown.
CPU CPU utilization.
At least one line is shown for the total occupation of all CPUs
together.
In case of a multi-processor system, an additional line is shown
for every individual processor (with `cpu' in lower case), sorted
on activity. Inactive CPUs will not be shown by default. The
lines showing the per-cpu occupation contain the cpu number in the
last field.
Every line contains the percentage of cpu time spent in kernel
mode by all active processes (`sys'), the percentage of cpu time
consumed in user mode (`user') for all active processes (including
processes running with a nice value larger than zero), the
percentage of cpu time spent for interrupt handling (`irq')
including softirq, the percentage of unused cpu time while no
processes were waiting for disk-I/O (`idle'), and the percentage
of unused cpu time while at least one process was waiting for
disk-I/O (`wait').
In case of per-cpu occupation, the last column shows the cpu
number and the wait percentage (`w') for that cpu. The number of
lines showing the per-cpu occupation can be limited.
For virtual machines the steal-percentage is shown (`steal'),
reflecting the percentage of cpu time stolen by other virtual
machines running on the same hardware.
For physical machines hosting one or more virtual machines, the
guest-percentage is shown (`guest'), reflecting the percentage of
cpu time used by the virtual machines. Notice that this percentage
overlaps the user-percentage.
In case of frequency-scaling, all previously mentioned CPU-
percentages are relative to the used scaling of the CPU during the
interval. If a CPU has been active for e.g. 50% in user mode
during the interval while the frequency-scaling of that CPU was
40%, only 20% of the full capacity of the CPU has been used in
user mode.
If the screen-width does not allow all of these counters, only a
relevant subset is shown.
CPL CPU load information.
This line contains the load average figures reflecting the number
of threads that are available to run on a CPU (i.e. part of the
runqueue) or that are waiting for disk I/O. These figures are
averaged over 1 (`avg1'), 5 (`avg5') and 15 (`avg15') minutes.
Furthermore the number of context switches (`csw'), the number of
serviced interrupts (`intr') and the number of available CPUs are
shown.
If the screen-width does not allow all of these counters, only a
relevant subset is shown.
MEM Memory occupation.
This line contains the total amount of physical memory (`tot'),
the amount of memory which is currently free (`free'), the amount
of memory in use as page cache including the total resident shared
memory (`cache'), the amount of memory within the page cache that
has to be flushed to disk (`dirty'), the amount of memory used for
filesystem meta data (`buff'), the amount of memory being used for
kernel mallocs (`slab'), the amount of slab memory that is
reclaimable (`slrec'), the resident size of shared memory
including tmpfs (`shmem`), the resident size of shared memory
(`shrss`) the amount of shared memory that is currently swapped
(`shswp`), the amount of memory that is currently claimed by
vmware's balloon driver (`vmbal`), the amount of memory that is
claimed for huge pages (`hptot`), and the amount of huge page
memory that is really in use (`hpuse`).
If the screen-width does not allow all of these counters, only a
relevant subset is shown.
SWP Swap occupation and overcommit info.
This line contains the total amount of swap space on disk (`tot')
and the amount of free swap space (`free').
Furthermore the committed virtual memory space (`vmcom') and the
maximum limit of the committed space (`vmlim', which is by default
swap size plus 50% of memory size) is shown. The committed space
is the reserved virtual space for all allocations of private
memory space for processes. The kernel only verifies whether the
committed space exceeds the limit if strict overcommit handling is
configured (vm.overcommit_memory is 2).
PAG Paging frequency.
This line contains the number of scanned pages (`scan') due to the
fact that free memory drops below a particular threshold and the
number times that the kernel tries to reclaim pages due to an
urgent need (`stall').
Also the number of memory pages the system read from swap space
(`swin') and the number of memory pages the system wrote to swap
space (`swout') are shown.
LVM/MDD/DSK
Logical volume/multiple device/disk utilization.
Per active unit one line is produced, sorted on unit activity.
Such line shows the name (e.g. VolGroup00-lvtmp for a logical
volume or sda for a hard disk), the busy percentage i.e. the
portion of time that the unit was busy handling requests (`busy'),
the number of read requests issued (`read'), the number of write
requests issued (`write'), the number of KiBytes per read
(`KiB/r'), the number of KiBytes per write (`KiB/w'), the number
of MiBytes per second throughput for reads (`MBr/s'), the number
of MiBytes per second throughput for writes (`MBw/s'), the average
queue depth (`avq') and the average number of milliseconds needed
by a request (`avio') for seek, latency and data transfer.
If the screen-width does not allow all of these counters, only a
relevant subset is shown.
The number of lines showing the units can be limited per class
(LVM, MDD or DSK) with the 'l' key or statically (see separate
man-page of pcp-atoprc(5)). By specifying the value 0 for a
particular class, no lines will be shown any more for that class.
NFM Network Filesystem (NFS) mount at the client side.
For each NFS-mounted filesystem, a line is shown that contains the
mounted server directory, the name of the server (`srv'), the
total number of bytes physically read from the server (`read') and
the total number of bytes physically written to the server
(`write'). Data transfer is subdivided in the number of bytes
read via normal read() system calls (`nread'), the number of bytes
written via normal read() system calls (`nwrit'), the number of
bytes read via direct I/O (`dread'), the number of bytes written
via direct I/O (`dwrit'), the number of bytes read via memory
mapped I/O pages (`mread'), and the number of bytes written via
memory mapped I/O pages (`mwrit').
NFC Network Filesystem (NFS) client side counters.
This line contains the number of RPC calls issues by local
processes (`rpc'), the number of read RPC calls (`read`) and write
RPC calls (`rpwrite') issued to the NFS server, the number of RPC
calls being retransmitted (`retxmit') and the number of
authorization refreshes (`autref').
NFS Network Filesystem (NFS) server side counters.
This line contains the number of RPC calls received from NFS
clients (`rpc'), the number of read RPC calls received (`cread`),
the number of write RPC calls received (`cwrit'), the number of
network requests handled via TCP (`nettcp'), the number of network
requests handled via UDP (`netudp'), the number of
Megabytes/second returned to read requests by clients (`MBcr/s`),
the number of Megabytes/second passed in write requests by clients
(`MBcw/s`), the number of reply cache hits (`rchits'), the number
of reply cache misses (`rcmiss') and the number of uncached
requests (`rcnoca'). Furthermore some error counters indicating
the number of requests with a bad format (`badfmt') or a bad
authorization (`badaut'), and a counter indicating the number of
bad clients (`badcln'). and the number of authorization refreshes
(`autref').
NET Network utilization (TCP/IP).
One line is shown for activity of the transport layer (TCP and
UDP), one line for the IP layer and one line per active interface.
For the transport layer, counters are shown concerning the number
of received TCP segments including those received in error
(`tcpi'), the number of transmitted TCP segments excluding those
containing only retransmitted octets (`tcpo'), the number of UDP
datagrams received (`udpi'), the number of UDP datagrams
transmitted (`udpo'), the number of active TCP opens (`tcpao'),
the number of passive TCP opens (`tcppo'), the number of TCP
output retransmissions (`tcprs'), the number of TCP input errors
(`tcpie'), the number of TCP output resets (`tcpor'), the number
of UDP no ports (`udpnp'), and the number of UDP input errors
(`udpie').
If the screen-width does not allow all of these counters, only a
relevant subset is shown.
These counters are related to IPv4 and IPv6 combined.
For the IP layer, counters are shown concerning the number of IP
datagrams received from interfaces, including those received in
error (`ipi'), the number of IP datagrams that local higher-layer
protocols offered for transmission (`ipo'), the number of received
IP datagrams which were forwarded to other interfaces (`ipfrw'),
the number of IP datagrams which were delivered to local higher-
layer protocols (`deliv'), the number of received ICMP datagrams
(`icmpi'), and the number of transmitted ICMP datagrams (`icmpo').
If the screen-width does not allow all of these counters, only a
relevant subset is shown.
These counters are related to IPv4 and IPv6 combined.
For every active network interface one line is shown, sorted on
the interface activity. Such line shows the name of the interface
and its busy percentage in the first column. The busy percentage
for half duplex is determined by comparing the interface speed
with the number of bits transmitted and received per second; for
full duplex the interface speed is compared with the highest of
either the transmitted or the received bits. When the interface
speed can not be determined (e.g. for the loopback interface),
`---' is shown instead of the percentage.
Furthermore the number of received packets (`pcki'), the number of
transmitted packets (`pcko'), the line speed of the interface
(`sp'), the effective amount of bits received per second (`si'),
the effective amount of bits transmitted per second (`so'), the
number of collisions (`coll'), the number of received multicast
packets (`mlti'), the number of errors while receiving a packet
(`erri'), the number of errors while transmitting a packet
(`erro'), the number of received packets dropped (`drpi'), and the
number of transmitted packets dropped (`drpo').
If the screen-width does not allow all of these counters, only a
relevant subset is shown.
The number of lines showing the network interfaces can be limited.
OUTPUT DESCRIPTION - PROCESS LEVEL
Following the system level information, the processes are shown from
which the resource utilization has changed during the last interval.
These processes might have used cpu time or issued disk or network
requests. However a process is also shown if part of it has been paged
out due to lack of memory (while the process itself was in sleep
state).
Per process the following fields may be shown (in alphabetical order),
depending on the current output mode as described in the section
INTERACTIVE COMMANDS and depending on the current width of your window:
AVGRSZ The average size of one read-action on disk.
AVGWSZ The average size of one write-action on disk.
CMD The name of the process. This name can be surrounded by
"less/greater than" signs (`<name>') which means that the
process has finished during the last interval.
Behind the abbreviation `CMD' in the header line, the current
page number and the total number of pages of the
process/thread list are shown.
COMMAND-LINE
The full command line of the process (including arguments). If
the length of the command line exceeds the length of the
screen line, the arrow keys -> and <- can be used for
horizontal scroll.
Behind the verb `COMMAND-LINE' in the header line, the current
page number and the total number of pages of the
process/thread list are shown.
CPU The occupation percentage of this process related to the
available capacity for this resource on system level.
CPUNR The identification of the CPU the (main) thread is running on
or has recently been running on.
DSK The occupation percentage of this process related to the total
load that is produced by all processes (i.e. total disk
accesses by all processes during the last interval).
This information is shown when per process "storage
accounting" is active in the kernel.
EGID Effective group-id under which this process executes.
ENDATE Date that the process has been finished. If the process is
still running, this field shows `active'.
ENTIME Time that the process has been finished. If the process is
still running, this field shows `active'.
ENVID Virtual environment identified (OpenVZ only).
EUID Effective user-id under which this process executes.
EXC The exit code of a terminated process (second position of
column `ST' is E) or the fatal signal number (second position
of column `ST' is S or C).
FSGID Filesystem group-id under which this process executes.
FSUID Filesystem user-id under which this process executes.
MAJFLT The number of page faults issued by this process that have
been solved by creating/loading the requested memory page.
MEM The occupation percentage of this process related to the
available capacity for this resource on system level.
MINFLT The number of page faults issued by this process that have
been solved by reclaiming the requested memory page from the
free list of pages.
NET The occupation percentage of this process related to the total
load that is produced by all processes (i.e. consumed network
bandwidth of all processes during the last interval).
This information will only be shown when kernel module
`netatop' is loaded.
NICE The more or less static priority that can be given to a
process on a scale from -20 (high priority) to +19 (low
priority).
NPROCS The number of active and terminated processes accumulated for
this user or program.
PID Process-id.
POLI The policies 'norm' (normal, which is SCHED_OTHER), 'btch'
(batch) and 'idle' refer to timesharing processes. The
policies 'fifo' (SCHED_FIFO) and 'rr' (round robin, which is
SCHED_RR) refer to realtime processes.
PPID Parent process-id.
PRI The process' priority ranges from 0 (highest priority) to 139
(lowest priority). Priority 0 to 99 are used for realtime
processes (fixed priority independent of their behavior) and
priority 100 to 139 for timesharing processes (variable
priority depending on their recent CPU consumption and the
nice value).
PSIZE The proportional memory size of this process (or user).
Every process shares resident memory with other processes.
E.g. when a particular program is started several times, the
code pages (text) are only loaded once in memory and shared by
all incarnations. Also the code of shared libraries is shared
by all processes using that shared library, as well as shared
memory and memory-mapped files. For the PSIZE calculation of
a process, the resident memory of a process that is shared
with other processes is divided by the number of sharers.
This means, that every process is accounted for a proportional
part of that memory. Accumulating the PSIZE values of all
processes in the system gives a reliable impression of the
total resident memory consumed by all processes.
Since gathering of all values that are needed to calculate the
PSIZE is a relatively time-consuming task, the 'R' key (or
'-R' flag) should be active. Gathering these values also
requires superuser privileges (otherwise '?K' is shown in the
output).
RDDSK When the kernel maintains standard io statistics (>= 2.6.20):
The read data transfer issued physically on disk (so reading
from the disk cache is not accounted for).
Unfortunately, the kernel aggregates the data tranfer of a
process to the data transfer of its parent process when
terminating, so you might see transfers for (parent) processes
like cron, bash or init, that are not really issued by them.
RGID The real group-id under which the process executes.
RGROW The amount of resident memory that the process has grown
during the last interval. A resident growth can be caused by
touching memory pages which were not physically created/loaded
before (load-on-demand). Note that a resident growth can also
be negative e.g. when part of the process is paged out due to
lack of memory or when the process frees dynamically allocated
memory. For a process which started during the last interval,
the resident growth reflects the total resident size of the
process at that moment.
RSIZE The total resident memory usage consumed by this process (or
user). Notice that the RSIZE of a process includes all
resident memory used by that process, even if certain memory
parts are shared with other processes (see also the
explanation of PSIZE).
RTPR Realtime priority according the POSIX standard. Value can be
0 for a timesharing process (policy 'norm', 'btch' or 'idle')
or ranges from 1 (lowest) till 99 (highest) for a realtime
process (policy 'rr' or 'fifo').
RUID The real user-id under which the process executes.
S The current state of the (main) thread: `R' for running
(currently processing or in the runqueue), `S' for sleeping
interruptible (wait for an event to occur), `D' for sleeping
non-interruptible, `Z' for zombie (waiting to be synchronized
with its parent process), `T' for stopped (suspended or
traced), `W' for swapping, and `E' (exit) for processes which
have finished during the last interval.
SGID The saved group-id of the process.
ST The status of a process.
The first position indicates if the process has been started
during the last interval (the value N means 'new process').
The second position indicates if the process has been finished
during the last interval.
The value E means 'exit' on the process' own initiative; the
exit code is displayed in the column `EXC'.
The value S means that the process has been terminated
unvoluntarily by a signal; the signal number is displayed in
the in the column `EXC'.
The value C means that the process has been terminated
unvoluntarily by a signal, producing a core dump in its
current directory; the signal number is displayed in the
column `EXC'.
STDATE The start date of the process.
STTIME The start time of the process.
SUID The saved user-id of the process.
SWAPSZ The swap space consumed by this process (or user).
SYSCPU CPU time consumption of this process in system mode (kernel
mode), usually due to system call handling.
THR Total number of threads within this process. All related
threads are contained in a thread group, represented by pcp-
atop as one line or as a separate line when the 'y' key (or -y
flag) is active.
On Linux 2.4 systems it is hardly possible to determine which
threads (i.e. processes) are related to the same thread group.
Every thread is represented by pcp-atop as a separate line.
TID Thread-id. All threads within a process run with the same PID
but with a different TID. This value is shown for individual
threads in multi-threaded processes (when using the key 'y').
TRUN Number of threads within this process that are in the state
'running' (R).
TSLPI Number of threads within this process that are in the state
'interruptible sleeping' (S).
TSLPU Number of threads within this process that are in the state
'uninterruptible sleeping' (D).
USRCPU CPU time consumption of this process in user mode, due to
processing the own program text.
VDATA The virtual memory size of the private data used by this
process (including heap and shared library data).
VGROW The amount of virtual memory that the process has grown during
the last interval. A virtual growth can be caused by e.g.
issueing a malloc() or attaching a shared memory segment. Note
that a virtual growth can also be negative by e.g. issueing a
free() or detaching a shared memory segment. For a process
which started during the last interval, the virtual growth
reflects the total virtual size of the process at that moment.
VSIZE The total virtual memory usage consumed by this process (or
user).
VSLIBS The virtual memory size of the (shared) text of all shared
libraries used by this process.
VSTACK The virtual memory size of the (private) stack used by this
process
VSTEXT The virtual memory size of the (shared) text of the executable
program.
WRDSK When the kernel maintains standard io statistics (>= 2.6.20):
The write data transfer issued physically on disk (so writing
to the disk cache is not accounted for). This counter is
maintained for the application process that writes its data to
the cache (assuming that this data is physically transferred
to disk later on). Notice that disk I/O needed for swapping is
not taken into account.
Unfortunately, the kernel aggregates the data tranfer of a
process to the data transfer of its parent process when
terminating, so you might see transfers for (parent) processes
like cron, bash or init, that are not really issued by them.
WCANCL When the kernel maintains standard io statistics (>= 2.6.20):
The write data transfer previously accounted for this process
or another process that has been cancelled. Suppose that a
process writes new data to a file and that data is removed
again before the cache buffers have been flushed to disk.
Then the original process shows the written data as WRDSK,
while the process that removes/truncates the file shows the
unflushed removed data as WCANCL.
PARSEABLE OUTPUT
With the flag -P followed by a list of one or more labels (comma-
separated), parseable output is produced for each sample. The labels
that can be specified for system-level statistics correspond to the
labels (first verb of each line) that can be found in the interactive
output: "CPU", "cpu" "CPL" "MEM", "SWP", "PAG", "LVM", "MDD", "DSK",
"NFM", "NFC", "NFS" and "NET".
For process-level statistics special labels are introduced: "PRG"
(general), "PRC" (cpu), "PRM" (memory), "PRD" (disk, only if "storage
accounting" is active) and "PRN" (network, only if the kernel module
'netatop' has been installed).
With the label "ALL", all system and process level statistics are
shown.
For every interval all requested lines are shown whereafter pcp-atop
shows a line just containing the label "SEP" as a separator before the
lines for the next sample are generated.
When a sample contains the values since boot, pcp-atop shows a line
just containing the label "RESET" before the lines for this sample are
generated.
The first part of each output-line consists of the following six
fields: label (the name of the label), host (the name of this machine),
epoch (the time of this interval as number of seconds since 1-1-1970),
date (date of this interval in format YYYY/MM/DD), time (time of this
interval in format HH:MM:SS), and interval (number of seconds elapsed
for this interval).
The subsequent fields of each output-line depend on the label:
CPU Subsequent fields: total number of clock-ticks per second for
this machine, number of processors, consumption for all CPUs
in system mode (clock-ticks), consumption for all CPUs in user
mode (clock-ticks), consumption for all CPUs in user mode for
niced processes (clock-ticks), consumption for all CPUs in
idle mode (clock-ticks), consumption for all CPUs in wait mode
(clock-ticks), consumption for all CPUs in irq mode (clock-
ticks), consumption for all CPUs in softirq mode (clock-
ticks), consumption for all CPUs in steal mode (clock-ticks),
consumption for all CPUs in guest mode (clock-ticks)
overlapping user mode, frequency of all CPUs and frequency
percentage of all CPUs.
cpu Subsequent fields: total number of clock-ticks per second for
this machine, processor-number, consumption for this CPU in
system mode (clock-ticks), consumption for this CPU in user
mode (clock-ticks), consumption for this CPU in user mode for
niced processes (clock-ticks), consumption for this CPU in
idle mode (clock-ticks), consumption for this CPU in wait mode
(clock-ticks), consumption for this CPU in irq mode (clock-
ticks), consumption for this CPU in softirq mode (clock-
ticks), consumption for this CPU in steal mode (clock-ticks),
consumption for this CPU in guest mode (clock-ticks)
overlapping user mode, frequency of this CPU and frequency
percentage of this CPU.
CPL Subsequent fields: number of processors, load average for last
minute, load average for last five minutes, load average for
last fifteen minutes, number of context-switches, and number
of device interrupts.
MEM Subsequent fields: page size for this machine (in bytes), size
of physical memory (pages), size of free memory (pages), size
of page cache (pages), size of buffer cache (pages), size of
slab (pages), dirty pages in cache (pages), reclaimable part
of slab (pages), size of vmware's balloon pages (pages), total
size of shared memory (pages), size of resident shared memory
(pages), size of swapped shared memory (pages), huge page size
(in bytes), total size of huge pages (huge pages), and size of
free huge pages (huge pages).
SWP Subsequent fields: page size for this machine (in bytes), size
of swap (pages), size of free swap (pages), 0 (future use),
size of committed space (pages), and limit for committed space
(pages).
PAG Subsequent fields: page size for this machine (in bytes),
number of page scans, number of allocstalls, 0 (future use),
number of swapins, and number of swapouts.
LVM/MDD/DSK
For every logical volume/multiple device/hard disk one line is
shown.
Subsequent fields: name, number of milliseconds spent for I/O,
number of reads issued, number of sectors transferred for
reads, number of writes issued, and number of sectors
transferred for write.
NFM Subsequent fields: mounted NFS filesystem, total number of
bytes read, total number of bytes written, number of bytes
read by normal system calls, number of bytes written by normal
system calls, number of bytes read by direct I/O, number of
bytes written by direct I/O, number of pages read by memory-
mapped I/O, and number of pages written by memory-mapped I/O.
NFC Subsequent fields: number of transmitted RPCs, number of
transmitted read RPCs, number of transmitted write RPCs,
number of RPC retransmissions, and number of authorization
refreshes.
NFS Subsequent fields: number of handled RPCs, number of received
read RPCs, number of received write RPCs, number of bytes read
by clients, number of bytes written by clients, number of RPCs
with bad format, number of RPCs with bad authorization, number
of RPCs from bad client, total number of handled network
requests, number of handled network requests via TCP, number
of handled network requests via UDP, number of handled TCP
connections, number of hits on reply cache, number of misses
on reply cache, and number of uncached requests.
NET First one line is produced for the upper layers of the TCP/IP
stack.
Subsequent fields: the verb "upper", number of packets
received by TCP, number of packets transmitted by TCP, number
of packets received by UDP, number of packets transmitted by
UDP, number of packets received by IP, number of packets
transmitted by IP, number of packets delivered to higher
layers by IP, and number of packets forwarded by IP.
Next one line is shown for every interface.
Subsequent fields: name of the interface, number of packets
received by the interface, number of bytes received by the
interface, number of packets transmitted by the interface,
number of bytes transmitted by the interface, interface speed,
and duplex mode (0=half, 1=full).
PRG For every process one line is shown.
Subsequent fields: PID (unique ID of task), name (between
brackets), state, real uid, real gid, TGID (group number of
related tasks/threads), total number of threads, exit code,
start time (epoch), full command line (between brackets),
PPID, number of threads in state 'running' (R), number of
threads in state 'interruptible sleeping' (S), number of
threads in state 'uninterruptible sleeping' (D), effective
uid, effective gid, saved uid, saved gid, filesystem uid,
filesystem gid, elapsed time (hertz), is_process (y/n),
virtual pid and container id.
PRC For every process one line is shown.
Subsequent fields: PID, name (between brackets), state, total
number of clock-ticks per second for this machine, CPU-
consumption in user mode (clockticks), CPU-consumption in
system mode (clockticks), nice value, priority, realtime
priority, scheduling policy, current CPU, sleep average, TGID
(group number of related tasks/threads) and is_process (y/n).
PRM For every process one line is shown.
Subsequent fields: PID, name (between brackets), state, page
size for this machine (in bytes), virtual memory size
(Kbytes), resident memory size (Kbytes), shared text memory
size (Kbytes), virtual memory growth (Kbytes), resident memory
growth (Kbytes), number of minor page faults, number of major
page faults, virtual library exec size (Kbytes), virtual data
size (Kbytes), virtual stack size (Kbytes), swap space used
(Kbytes), TGID (group number of related tasks/threads),
is_process (y/n) and proportional set size (Kbytes) if in 'R'
option is specified.
PRD For every process one line is shown.
Subsequent fields: PID, name (between brackets), state,
obsoleted kernel patch installed ('n'), standard io statistics
used ('y' or 'n'), number of reads on disk, cumulative number
of sectors read, number of writes on disk, cumulative number
of sectors written, cancelled number of written sectors, TGID
(group number of related tasks/threads) and is_process (y/n).
If the standard I/O statistics (>= 2.6.20) are not used, the
disk I/O counters per process are not relevant. The counters
'number of reads on disk' and 'number of writes on disk' are
obsoleted anyhow.
PRN For every process one line is shown.
Subsequent fields: PID, name (between brackets), state, kernel
module 'netatop' loaded ('y' or 'n'), number of TCP-packets
transmitted, cumulative size of TCP-packets transmitted,
number of TCP-packets received, cumulative size of TCP-packets
received, number of UDP-packets transmitted, cumulative size
of UDP-packets transmitted, number of UDP-packets received,
cumulative size of UDP-packets transmitted, number of raw
packets transmitted (obsolete, always 0), number of raw
packets received (obsolete, always 0), TGID (group number of
related tasks/threads) and is_process (y/n).
EXAMPLES
To monitor the current system load interactively with an interval of 5
seconds:
pcp atop 5
To monitor the system load and write it to a file (in plain ASCII) with
an interval of one minute during half an hour with active processes
sorted on memory consumption:
pcp atop -M 60 30 > /log/pcp-atop.mem
Store information about the system and process activity in a PCP
archive folio with an interval of ten minutes during an hour:
pcp atop -w /tmp/pcp-atop 600 6
View the contents of this file interactively:
pcp atop -r /tmp/pcp-atop
View the processor and disk utilization of this file in parseable
format:
pcp atop -PCPU,DSK -r /tmp/pcp-atop.raw
View the contents of today's standard logfile interactively:
pcp atop -r
View the contents of the standard logfile of the day before yesterday
interactively:
pcp atop -r yy
View the contents of the standard logfile of 2014, June 7 from 02:00 PM
onwards interactively:
pcp atop -r 20140607 -b 14:00
FILES
/etc/atoprc
Configuration file containing system-wide default values. See
related man-page.
~/.atoprc
Configuration file containing personal default values. See
related man-page.
NOTES
pcp-atop is based on the source code of the atop(1) command from http://atoptool.nl and aims to be command line and output compatible with it as much as possible. Some features of that atop command are not available in pcp-atop. Some features of pcp-atop (such as reporting on the Apache HTTP daemon, and NFS client mounts) are only activated if the corresonding PCP metrics are available. Refer to the documentation for pmdaapache(1) and pmdanfsclient(1) for further details on activating these metrics.
SEE ALSO
pcp(1), pcp-atopsar(1), pmdaapache(1), pmdanfsclient(1), mkaf(1), pmlogger(1), pmlogger_daily(1), PCPIntro(1) and pcp-atoprc(5).
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