tools/perf/Documentation/perf-top.txt

   1 perf-top(1)
   2 ===========
   3
   4 NAME
   5 ----
   6 perf-top - System profiling tool.
   7
   8 SYNOPSIS
   9 --------
  10 [verse]
  11 'perf top' [-e <EVENT> | --event=EVENT] [<options>]
  12
  13 DESCRIPTION
  14 -----------
  15 This command generates and displays a performance counter profile in real time.
  16
  17
  18 OPTIONS
  19 -------
  20 -a::
  21 --all-cpus::
  22         System-wide collection.  (default)
  23
  24 -c <count>::
  25 --count=<count>::
  26         Event period to sample.
  27
  28 -C <cpu-list>::
  29 --cpu=<cpu>::
  30 Monitor only on the list of CPUs provided. Multiple CPUs can be provided as a
  31 comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2.
  32 Default is to monitor all CPUS.
  33
  34 -d <seconds>::
  35 --delay=<seconds>::
  36         Number of seconds to delay between refreshes.
  37
  38 -e <event>::
  39 --event=<event>::
  40         Select the PMU event. Selection can be a symbolic event name
  41         (use 'perf list' to list all events) or a raw PMU
  42         event (eventsel+umask) in the form of rNNN where NNN is a
  43         hexadecimal event descriptor.
  44
  45 -E <entries>::
  46 --entries=<entries>::
  47         Display this many functions.
  48
  49 -f <count>::
  50 --count-filter=<count>::
  51         Only display functions with more events than this.
  52
  53 --group::
  54         Put the counters into a counter group.
  55
  56 -F <freq>::
  57 --freq=<freq>::
  58         Profile at this frequency.
  59
  60 -i::
  61 --inherit::
  62         Child tasks do not inherit counters.
  63
  64 -k <path>::
  65 --vmlinux=<path>::
  66         Path to vmlinux.  Required for annotation functionality.
  67
  68 -m <pages>::
  69 --mmap-pages=<pages>::
  70         Number of mmap data pages (must be a power of two) or size
  71         specification with appended unit character - B/K/M/G. The
  72         size is rounded up to have nearest pages power of two value.
  73
  74 -p <pid>::
  75 --pid=<pid>::
  76         Profile events on existing Process ID (comma separated list).
  77
  78 -t <tid>::
  79 --tid=<tid>::
  80         Profile events on existing thread ID (comma separated list).
  81
  82 -u::
  83 --uid=::
  84         Record events in threads owned by uid. Name or number.
  85
  86 -r <priority>::
  87 --realtime=<priority>::
  88         Collect data with this RT SCHED_FIFO priority.
  89
  90 --sym-annotate=<symbol>::
  91         Annotate this symbol.
  92
  93 -K::
  94 --hide_kernel_symbols::
  95         Hide kernel symbols.
  96
  97 -U::
  98 --hide_user_symbols::
  99         Hide user symbols.
 100
 101 -D::
 102 --dump-symtab::
 103         Dump the symbol table used for profiling.
 104
 105 -v::
 106 --verbose::
 107         Be more verbose (show counter open errors, etc).
 108
 109 -z::
 110 --zero::
 111         Zero history across display updates.
 112
 113 -s::
 114 --sort::
 115         Sort by key(s): pid, comm, dso, symbol, parent, srcline, weight,
 116         local_weight, abort, in_tx, transaction, overhead, sample, period.
 117         Please see description of --sort in the perf-report man page.
 118
 119 --fields=::
 120         Specify output field - multiple keys can be specified in CSV format.
 121         Following fields are available:
 122         overhead, overhead_sys, overhead_us, overhead_children, sample and period.
 123         Also it can contain any sort key(s).
 124
 125         By default, every sort keys not specified in --field will be appended
 126         automatically.
 127
 128 -n::
 129 --show-nr-samples::
 130         Show a column with the number of samples.
 131
 132 --show-total-period::
 133         Show a column with the sum of periods.
 134
 135 --dsos::
 136         Only consider symbols in these dsos.  This option will affect the
 137         percentage of the overhead column.  See --percentage for more info.
 138
 139 --comms::
 140         Only consider symbols in these comms.  This option will affect the
 141         percentage of the overhead column.  See --percentage for more info.
 142
 143 --symbols::
 144         Only consider these symbols.  This option will affect the
 145         percentage of the overhead column.  See --percentage for more info.
 146
 147 -M::
 148 --disassembler-style=:: Set disassembler style for objdump.
 149
 150 --source::
 151         Interleave source code with assembly code. Enabled by default,
 152         disable with --no-source.
 153
 154 --asm-raw::
 155         Show raw instruction encoding of assembly instructions.
 156
 157 -g::
 158         Enables call-graph (stack chain/backtrace) recording.
 159
 160 --call-graph::
 161         Setup and enable call-graph (stack chain/backtrace) recording,
 162         implies -g.
 163
 164 --children::
 165         Accumulate callchain of children to parent entry so that then can
 166         show up in the output.  The output will have a new "Children" column
 167         and will be sorted on the data.  It requires -g/--call-graph option
 168         enabled.
 169
 170 --max-stack::
 171         Set the stack depth limit when parsing the callchain, anything
 172         beyond the specified depth will be ignored. This is a trade-off
 173         between information loss and faster processing especially for
 174         workloads that can have a very long callchain stack.
 175
 176         Default: 127
 177
 178 --ignore-callees=<regex>::
 179         Ignore callees of the function(s) matching the given regex.
 180         This has the effect of collecting the callers of each such
 181         function into one place in the call-graph tree.
 182
 183 --percent-limit::
 184         Do not show entries which have an overhead under that percent.
 185         (Default: 0).
 186
 187 --percentage::
 188         Determine how to display the overhead percentage of filtered entries.
 189         Filters can be applied by --comms, --dsos and/or --symbols options and
 190         Zoom operations on the TUI (thread, dso, etc).
 191
 192         "relative" means it's relative to filtered entries only so that the
 193         sum of shown entries will be always 100%. "absolute" means it retains
 194         the original value before and after the filter is applied.
 195
 196 -w::
 197 --column-widths=<width[,width...]>::
 198         Force each column width to the provided list, for large terminal
 199         readability.  0 means no limit (default behavior).
 200
 201
 202 INTERACTIVE PROMPTING KEYS
 203 --------------------------
 204
 205 [d]::
 206         Display refresh delay.
 207
 208 [e]::
 209         Number of entries to display.
 210
 211 [E]::
 212         Event to display when multiple counters are active.
 213
 214 [f]::
 215         Profile display filter (>= hit count).
 216
 217 [F]::
 218         Annotation display filter (>= % of total).
 219
 220 [s]::
 221         Annotate symbol.
 222
 223 [S]::
 224         Stop annotation, return to full profile display.
 225
 226 [z]::
 227         Toggle event count zeroing across display updates.
 228
 229 [qQ]::
 230         Quit.
 231
 232 Pressing any unmapped key displays a menu, and prompts for input.
 233
 234
 235 SEE ALSO
 236 --------
 237 linkperf:perf-stat[1], linkperf:perf-list[1], linkperf:perf-report[1]