1 perf-stat(1) 1 perf-stat(1) 2 ============ 2 ============ 3 3 4 NAME 4 NAME 5 ---- 5 ---- 6 perf-stat - Run a command and gather performan 6 perf-stat - Run a command and gather performance counter statistics 7 7 8 SYNOPSIS 8 SYNOPSIS 9 -------- 9 -------- 10 [verse] 10 [verse] 11 'perf stat' [-e <EVENT> | --event=EVENT] [-a] 11 'perf stat' [-e <EVENT> | --event=EVENT] [-a] <command> 12 'perf stat' [-e <EVENT> | --event=EVENT] [-a] !! 12 'perf stat' [-e <EVENT> | --event=EVENT] [-a] -- <command> [<options>] 13 'perf stat' [-e <EVENT> | --event=EVENT] [-a] !! 13 'perf stat' [-e <EVENT> | --event=EVENT] [-a] record [-o file] -- <command> [<options>] 14 'perf stat' report [-i file] 14 'perf stat' report [-i file] 15 15 16 DESCRIPTION 16 DESCRIPTION 17 ----------- 17 ----------- 18 This command runs a command and gathers perfor 18 This command runs a command and gathers performance counter statistics 19 from it. 19 from it. 20 20 21 21 22 OPTIONS 22 OPTIONS 23 ------- 23 ------- 24 <command>...:: 24 <command>...:: 25 Any command you can specify in a shell 25 Any command you can specify in a shell. 26 26 27 record:: 27 record:: 28 See STAT RECORD. 28 See STAT RECORD. 29 29 30 report:: 30 report:: 31 See STAT REPORT. 31 See STAT REPORT. 32 32 33 -e:: 33 -e:: 34 --event=:: 34 --event=:: 35 Select the PMU event. Selection can be 35 Select the PMU event. Selection can be: 36 36 37 - a symbolic event name (use 'perf lis 37 - a symbolic event name (use 'perf list' to list all events) 38 38 39 - a raw PMU event in the form of rN wh !! 39 - a raw PMU event (eventsel+umask) in the form of rNNN where NNN is a 40 that represents the raw register enc !! 40 hexadecimal event descriptor. 41 event control registers as described << 42 /sys/bus/event_source/devices/cpu/fo << 43 41 44 - a symbolic or raw PMU event followed 42 - a symbolic or raw PMU event followed by an optional colon 45 and a list of event modifiers, e.g., 43 and a list of event modifiers, e.g., cpu-cycles:p. See the 46 linkperf:perf-list[1] man page for d 44 linkperf:perf-list[1] man page for details on event modifiers. 47 45 48 - a symbolically formed event like 'pm 46 - a symbolically formed event like 'pmu/param1=0x3,param2/' where 49 param1 and param2 are defined as for 47 param1 and param2 are defined as formats for the PMU in 50 /sys/bus/event_source/devices/<pmu>/ 48 /sys/bus/event_source/devices/<pmu>/format/* 51 49 52 'percore' is a event qualifier that 50 'percore' is a event qualifier that sums up the event counts for both 53 hardware threads in a core. For exam 51 hardware threads in a core. For example: 54 perf stat -A -a -e cpu/event,percore 52 perf stat -A -a -e cpu/event,percore=1/,otherevent ... 55 53 56 - a symbolically formed event like 'pm 54 - a symbolically formed event like 'pmu/config=M,config1=N,config2=K/' 57 where M, N, K are numbers (in decima 55 where M, N, K are numbers (in decimal, hex, octal format). 58 Acceptable values for each of 'confi 56 Acceptable values for each of 'config', 'config1' and 'config2' 59 parameters are defined by correspond 57 parameters are defined by corresponding entries in 60 /sys/bus/event_source/devices/<pmu>/ 58 /sys/bus/event_source/devices/<pmu>/format/* 61 59 62 Note that the last two syntaxes suppor 60 Note that the last two syntaxes support prefix and glob matching in 63 the PMU name to simplify creation of e 61 the PMU name to simplify creation of events across multiple instances 64 of the same type of PMU in large syste 62 of the same type of PMU in large systems (e.g. memory controller PMUs). 65 Multiple PMU instances are typical for 63 Multiple PMU instances are typical for uncore PMUs, so the prefix 66 'uncore_' is also ignored when perform 64 'uncore_' is also ignored when performing this match. 67 65 68 66 69 -i:: 67 -i:: 70 --no-inherit:: 68 --no-inherit:: 71 child tasks do not inherit counters 69 child tasks do not inherit counters 72 -p:: 70 -p:: 73 --pid=<pid>:: 71 --pid=<pid>:: 74 stat events on existing process id (co 72 stat events on existing process id (comma separated list) 75 73 76 -t:: 74 -t:: 77 --tid=<tid>:: 75 --tid=<tid>:: 78 stat events on existing thread id (com 76 stat events on existing thread id (comma separated list) 79 77 80 -b:: << 81 --bpf-prog:: << 82 stat events on existing bpf program id << 83 requiring root rights. bpftool-prog co << 84 id all bpf programs in the system. For << 85 << 86 # bpftool prog | head -n 1 << 87 17247: tracepoint name sys_enter tag 192d5 << 88 << 89 # perf stat -e cycles,instructions --bpf-pro << 90 << 91 Performance counter stats for 'BPF program( << 92 << 93 85,967 cycles << 94 28,982 instructions << 95 << 96 1.102235068 seconds time elapsed << 97 << 98 --bpf-counters:: << 99 Use BPF programs to aggregate readings << 100 allows multiple perf-stat sessions tha << 101 instructions, etc.) to share hardware << 102 To use BPF programs on common events b << 103 "perf config stat.bpf-counter-events=< << 104 << 105 --bpf-attr-map:: << 106 With option "--bpf-counters", differen << 107 information about shared BPF programs << 108 Use "--bpf-attr-map" to specify the pa << 109 The default path is /sys/fs/bpf/perf_a << 110 << 111 ifdef::HAVE_LIBPFM[] 78 ifdef::HAVE_LIBPFM[] 112 --pfm-events events:: 79 --pfm-events events:: 113 Select a PMU event using libpfm4 syntax (see h 80 Select a PMU event using libpfm4 syntax (see http://perfmon2.sf.net) 114 including support for event filters. For examp 81 including support for event filters. For example '--pfm-events 115 inst_retired:any_p:u:c=1:i'. More than one eve 82 inst_retired:any_p:u:c=1:i'. More than one event can be passed to the 116 option using the comma separator. Hardware eve 83 option using the comma separator. Hardware events and generic hardware 117 events cannot be mixed together. The latter mu 84 events cannot be mixed together. The latter must be used with the -e 118 option. The -e option and this one can be mixe 85 option. The -e option and this one can be mixed and matched. Events 119 can be grouped using the {} notation. 86 can be grouped using the {} notation. 120 endif::HAVE_LIBPFM[] 87 endif::HAVE_LIBPFM[] 121 88 122 -a:: 89 -a:: 123 --all-cpus:: 90 --all-cpus:: 124 system-wide collection from all CPUs ( 91 system-wide collection from all CPUs (default if no target is specified) 125 92 126 --no-scale:: 93 --no-scale:: 127 Don't scale/normalize counter values 94 Don't scale/normalize counter values 128 95 129 -d:: 96 -d:: 130 --detailed:: 97 --detailed:: 131 print more detailed statistics, can be 98 print more detailed statistics, can be specified up to 3 times 132 99 133 -d: detailed events, L1 an 100 -d: detailed events, L1 and LLC data cache 134 -d -d: more detailed events, dTLB 101 -d -d: more detailed events, dTLB and iTLB events 135 -d -d -d: very detailed events, addin 102 -d -d -d: very detailed events, adding prefetch events 136 103 137 -r:: 104 -r:: 138 --repeat=<n>:: 105 --repeat=<n>:: 139 repeat command and print average + std 106 repeat command and print average + stddev (max: 100). 0 means forever. 140 107 141 -B:: 108 -B:: 142 --big-num:: 109 --big-num:: 143 print large numbers with thousands' se 110 print large numbers with thousands' separators according to locale. 144 Enabled by default. Use "--no-big-num" 111 Enabled by default. Use "--no-big-num" to disable. 145 Default setting can be changed with "p 112 Default setting can be changed with "perf config stat.big-num=false". 146 113 147 -C:: 114 -C:: 148 --cpu=:: 115 --cpu=:: 149 Count only on the list of CPUs provided. Multi 116 Count only on the list of CPUs provided. Multiple CPUs can be provided as a 150 comma-separated list with no space: 0,1. Range 117 comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2. 151 In per-thread mode, this option is ignored. Th 118 In per-thread mode, this option is ignored. The -a option is still necessary 152 to activate system-wide monitoring. Default is 119 to activate system-wide monitoring. Default is to count on all CPUs. 153 120 154 -A:: 121 -A:: 155 --no-aggr:: 122 --no-aggr:: 156 Do not aggregate counts across all monitored C 123 Do not aggregate counts across all monitored CPUs. 157 124 158 -n:: 125 -n:: 159 --null:: 126 --null:: 160 null run - Don't start any counters. !! 127 null run - don't start any counters 161 << 162 This can be useful to measure just elapsed wal << 163 raw overhead of perf stat itself, without runn << 164 128 165 -v:: 129 -v:: 166 --verbose:: 130 --verbose:: 167 be more verbose (show counter open err 131 be more verbose (show counter open errors, etc) 168 132 169 -x SEP:: 133 -x SEP:: 170 --field-separator SEP:: 134 --field-separator SEP:: 171 print counts using a CSV-style output to make 135 print counts using a CSV-style output to make it easy to import directly into 172 spreadsheets. Columns are separated by the str 136 spreadsheets. Columns are separated by the string specified in SEP. 173 137 174 --table:: Display time for each run (-r option 138 --table:: Display time for each run (-r option), in a table format, e.g.: 175 139 176 $ perf stat --null -r 5 --table perf bench s 140 $ perf stat --null -r 5 --table perf bench sched pipe 177 141 178 Performance counter stats for 'perf bench s 142 Performance counter stats for 'perf bench sched pipe' (5 runs): 179 143 180 # Table of individual measurement 144 # Table of individual measurements: 181 5.189 (-0.293) # 145 5.189 (-0.293) # 182 5.189 (-0.294) # 146 5.189 (-0.294) # 183 5.186 (-0.296) # 147 5.186 (-0.296) # 184 5.663 (+0.181) ## 148 5.663 (+0.181) ## 185 6.186 (+0.703) #### 149 6.186 (+0.703) #### 186 150 187 # Final result: 151 # Final result: 188 5.483 +- 0.198 seconds time elaps 152 5.483 +- 0.198 seconds time elapsed ( +- 3.62% ) 189 153 190 -G name:: 154 -G name:: 191 --cgroup name:: 155 --cgroup name:: 192 monitor only in the container (cgroup) called 156 monitor only in the container (cgroup) called "name". This option is available only 193 in per-cpu mode. The cgroup filesystem must be 157 in per-cpu mode. The cgroup filesystem must be mounted. All threads belonging to 194 container "name" are monitored when they run o 158 container "name" are monitored when they run on the monitored CPUs. Multiple cgroups 195 can be provided. Each cgroup is applied to the 159 can be provided. Each cgroup is applied to the corresponding event, i.e., first cgroup 196 to first event, second cgroup to second event 160 to first event, second cgroup to second event and so on. It is possible to provide 197 an empty cgroup (monitor all the time) using, 161 an empty cgroup (monitor all the time) using, e.g., -G foo,,bar. Cgroups must have 198 corresponding events, i.e., they always refer 162 corresponding events, i.e., they always refer to events defined earlier on the command 199 line. If the user wants to track multiple even 163 line. If the user wants to track multiple events for a specific cgroup, the user can 200 use '-e e1 -e e2 -G foo,foo' or just use '-e e 164 use '-e e1 -e e2 -G foo,foo' or just use '-e e1 -e e2 -G foo'. 201 165 202 If wanting to monitor, say, 'cycles' for a cgr 166 If wanting to monitor, say, 'cycles' for a cgroup and also for system wide, this 203 command line can be used: 'perf stat -e cycles 167 command line can be used: 'perf stat -e cycles -G cgroup_name -a -e cycles'. 204 168 205 --for-each-cgroup name:: << 206 Expand event list for each cgroup in "name" (a << 207 by comma). It also support regex patterns to << 208 effect that repeating -e option and -G option << 209 cannot be used with -G/--cgroup option. << 210 << 211 -o file:: 169 -o file:: 212 --output file:: 170 --output file:: 213 Print the output into the designated file. 171 Print the output into the designated file. 214 172 215 --append:: 173 --append:: 216 Append to the output file designated with the 174 Append to the output file designated with the -o option. Ignored if -o is not specified. 217 175 218 --log-fd:: 176 --log-fd:: 219 177 220 Log output to fd, instead of stderr. Compleme 178 Log output to fd, instead of stderr. Complementary to --output, and mutually exclusive 221 with it. --append may be used here. Examples 179 with it. --append may be used here. Examples: 222 3>results perf stat --log-fd 3 !! 180 3>results perf stat --log-fd 3 -- $cmd 223 3>>results perf stat --log-fd 3 --append !! 181 3>>results perf stat --log-fd 3 --append -- $cmd 224 182 225 --control=fifo:ctl-fifo[,ack-fifo]:: !! 183 --control fd:ctl-fd[,ack-fd] 226 --control=fd:ctl-fd[,ack-fd]:: << 227 ctl-fifo / ack-fifo are opened and used as ctl << 228 Listen on ctl-fd descriptor for command to con 184 Listen on ctl-fd descriptor for command to control measurement ('enable': enable events, 229 'disable': disable events). Measurements can b 185 'disable': disable events). Measurements can be started with events disabled using 230 --delay=-1 option. Optionally send control com 186 --delay=-1 option. Optionally send control command completion ('ack\n') to ack-fd descriptor 231 to synchronize with the controlling process. E 187 to synchronize with the controlling process. Example of bash shell script to enable and 232 disable events during measurements: 188 disable events during measurements: 233 189 234 #!/bin/bash !! 190 #!/bin/bash 235 191 236 ctl_dir=/tmp/ !! 192 ctl_dir=/tmp/ 237 193 238 ctl_fifo=${ctl_dir}perf_ctl.fifo !! 194 ctl_fifo=${ctl_dir}perf_ctl.fifo 239 test -p ${ctl_fifo} && unlink ${ctl_fifo} !! 195 test -p ${ctl_fifo} && unlink ${ctl_fifo} 240 mkfifo ${ctl_fifo} !! 196 mkfifo ${ctl_fifo} 241 exec {ctl_fd}<>${ctl_fifo} !! 197 exec {ctl_fd}<>${ctl_fifo} 242 198 243 ctl_ack_fifo=${ctl_dir}perf_ctl_ack.fifo !! 199 ctl_ack_fifo=${ctl_dir}perf_ctl_ack.fifo 244 test -p ${ctl_ack_fifo} && unlink ${ctl_ack_f !! 200 test -p ${ctl_ack_fifo} && unlink ${ctl_ack_fifo} 245 mkfifo ${ctl_ack_fifo} !! 201 mkfifo ${ctl_ack_fifo} 246 exec {ctl_fd_ack}<>${ctl_ack_fifo} !! 202 exec {ctl_fd_ack}<>${ctl_ack_fifo} 247 203 248 perf stat -D -1 -e cpu-cycles -a -I 1000 !! 204 perf stat -D -1 -e cpu-cycles -a -I 1000 \ 249 --control fd:${ctl_fd},${ctl_fd_ack !! 205 --control fd:${ctl_fd},${ctl_fd_ack} \ 250 \-- sleep 30 & !! 206 -- sleep 30 & 251 perf_pid=$! !! 207 perf_pid=$! 252 208 253 sleep 5 && echo 'enable' >&${ctl_fd} && read !! 209 sleep 5 && echo 'enable' >&${ctl_fd} && read -u ${ctl_fd_ack} e1 && echo "enabled(${e1})" 254 sleep 10 && echo 'disable' >&${ctl_fd} && rea !! 210 sleep 10 && echo 'disable' >&${ctl_fd} && read -u ${ctl_fd_ack} d1 && echo "disabled(${d1})" 255 211 256 exec {ctl_fd_ack}>&- !! 212 exec {ctl_fd_ack}>&- 257 unlink ${ctl_ack_fifo} !! 213 unlink ${ctl_ack_fifo} 258 214 259 exec {ctl_fd}>&- !! 215 exec {ctl_fd}>&- 260 unlink ${ctl_fifo} !! 216 unlink ${ctl_fifo} 261 217 262 wait -n ${perf_pid} !! 218 wait -n ${perf_pid} 263 exit $? !! 219 exit $? 264 220 265 221 266 --pre:: 222 --pre:: 267 --post:: 223 --post:: 268 Pre and post measurement hooks, e.g.: 224 Pre and post measurement hooks, e.g.: 269 225 270 perf stat --repeat 10 --null --sync --pre 'mak !! 226 perf stat --repeat 10 --null --sync --pre 'make -s O=defconfig-build/clean' -- make -s -j64 O=defconfig-build/ bzImage 271 227 272 -I msecs:: 228 -I msecs:: 273 --interval-print msecs:: 229 --interval-print msecs:: 274 Print count deltas every N milliseconds (minim 230 Print count deltas every N milliseconds (minimum: 1ms) 275 The overhead percentage could be high in some 231 The overhead percentage could be high in some cases, for instance with small, sub 100ms intervals. Use with caution. 276 example: 'perf stat -I 1000 -e cycles 232 example: 'perf stat -I 1000 -e cycles -a sleep 5' 277 233 278 If the metric exists, it is calculated by the 234 If the metric exists, it is calculated by the counts generated in this interval and the metric is printed after #. 279 235 280 --interval-count times:: 236 --interval-count times:: 281 Print count deltas for fixed number of times. 237 Print count deltas for fixed number of times. 282 This option should be used together with "-I" 238 This option should be used together with "-I" option. 283 example: 'perf stat -I 1000 --interval 239 example: 'perf stat -I 1000 --interval-count 2 -e cycles -a' 284 240 285 --interval-clear:: 241 --interval-clear:: 286 Clear the screen before next interval. 242 Clear the screen before next interval. 287 243 288 --timeout msecs:: 244 --timeout msecs:: 289 Stop the 'perf stat' session and print count d 245 Stop the 'perf stat' session and print count deltas after N milliseconds (minimum: 10 ms). 290 This option is not supported with the "-I" opt 246 This option is not supported with the "-I" option. 291 example: 'perf stat --time 2000 -e cyc 247 example: 'perf stat --time 2000 -e cycles -a' 292 248 293 --metric-only:: 249 --metric-only:: 294 Only print computed metrics. Print them in a s 250 Only print computed metrics. Print them in a single line. 295 Don't show any raw values. Not supported with 251 Don't show any raw values. Not supported with --per-thread. 296 252 297 --per-socket:: 253 --per-socket:: 298 Aggregate counts per processor socket for syst 254 Aggregate counts per processor socket for system-wide mode measurements. This 299 is a useful mode to detect imbalance between s 255 is a useful mode to detect imbalance between sockets. To enable this mode, 300 use --per-socket in addition to -a. (system-wi 256 use --per-socket in addition to -a. (system-wide). The output includes the 301 socket number and the number of online process 257 socket number and the number of online processors on that socket. This is 302 useful to gauge the amount of aggregation. 258 useful to gauge the amount of aggregation. 303 259 304 --per-die:: 260 --per-die:: 305 Aggregate counts per processor die for system- 261 Aggregate counts per processor die for system-wide mode measurements. This 306 is a useful mode to detect imbalance between d 262 is a useful mode to detect imbalance between dies. To enable this mode, 307 use --per-die in addition to -a. (system-wide) 263 use --per-die in addition to -a. (system-wide). The output includes the 308 die number and the number of online processors 264 die number and the number of online processors on that die. This is 309 useful to gauge the amount of aggregation. 265 useful to gauge the amount of aggregation. 310 266 311 --per-cluster:: << 312 Aggregate counts per processor cluster for sys << 313 is a useful mode to detect imbalance between c << 314 use --per-cluster in addition to -a. (system-w << 315 cluster number and the number of online proces << 316 useful to gauge the amount of aggregation. The << 317 related CPUs can be gotten from /sys/devices/s << 318 << 319 --per-cache:: << 320 Aggregate counts per cache instance for system << 321 default, the aggregation happens for the cache << 322 in the system. To specify a particular level, << 323 alongside the option in the format [Ll][1-9][0 << 324 Using option "--per-cache=l3" or "--per-cache= << 325 information at the boundary of the level 3 cac << 326 << 327 --per-core:: 267 --per-core:: 328 Aggregate counts per physical processor for sy 268 Aggregate counts per physical processor for system-wide mode measurements. This 329 is a useful mode to detect imbalance between p 269 is a useful mode to detect imbalance between physical cores. To enable this mode, 330 use --per-core in addition to -a. (system-wide 270 use --per-core in addition to -a. (system-wide). The output includes the 331 core number and the number of online logical p 271 core number and the number of online logical processors on that physical processor. 332 272 333 --per-thread:: 273 --per-thread:: 334 Aggregate counts per monitored threads, when m 274 Aggregate counts per monitored threads, when monitoring threads (-t option) 335 or processes (-p option). 275 or processes (-p option). 336 276 337 --per-node:: 277 --per-node:: 338 Aggregate counts per NUMA nodes for system-wid 278 Aggregate counts per NUMA nodes for system-wide mode measurements. This 339 is a useful mode to detect imbalance between N 279 is a useful mode to detect imbalance between NUMA nodes. To enable this 340 mode, use --per-node in addition to -a. (syste 280 mode, use --per-node in addition to -a. (system-wide). 341 281 342 -D msecs:: 282 -D msecs:: 343 --delay msecs:: 283 --delay msecs:: 344 After starting the program, wait msecs before 284 After starting the program, wait msecs before measuring (-1: start with events 345 disabled). This is useful to filter out the st 285 disabled). This is useful to filter out the startup phase of the program, 346 which is often very different. 286 which is often very different. 347 287 348 -T:: 288 -T:: 349 --transaction:: 289 --transaction:: 350 290 351 Print statistics of transactional execution if 291 Print statistics of transactional execution if supported. 352 292 353 --metric-no-group:: 293 --metric-no-group:: 354 By default, events to compute a metric are pla 294 By default, events to compute a metric are placed in weak groups. The 355 group tries to enforce scheduling all or none 295 group tries to enforce scheduling all or none of the events. The 356 --metric-no-group option places events outside 296 --metric-no-group option places events outside of groups and may 357 increase the chance of the event being schedul 297 increase the chance of the event being scheduled - leading to more 358 accuracy. However, as events may not be schedu 298 accuracy. However, as events may not be scheduled together accuracy 359 for metrics like instructions per cycle can be 299 for metrics like instructions per cycle can be lower - as both metrics 360 may no longer be being measured at the same ti 300 may no longer be being measured at the same time. 361 301 362 --metric-no-merge:: 302 --metric-no-merge:: 363 By default metric events in different weak gro 303 By default metric events in different weak groups can be shared if one 364 group contains all the events needed by anothe 304 group contains all the events needed by another. In such cases one 365 group will be eliminated reducing event multip 305 group will be eliminated reducing event multiplexing and making it so 366 that certain groups of metrics sum to 100%. A 306 that certain groups of metrics sum to 100%. A downside to sharing a 367 group is that the group may require multiplexi 307 group is that the group may require multiplexing and so accuracy for a 368 small group that need not have multiplexing is 308 small group that need not have multiplexing is lowered. This option 369 forbids the event merging logic from sharing e 309 forbids the event merging logic from sharing events between groups and 370 may be used to increase accuracy in this case. 310 may be used to increase accuracy in this case. 371 311 372 --metric-no-threshold:: << 373 Metric thresholds may increase the number of e << 374 compute whether a metric has exceeded its thre << 375 may not be desirable, for example, as the even << 376 multiplexing. This option disables the adding << 377 events for a metric. However, if there are suf << 378 compute the threshold then the threshold is st << 379 color the metric's computed value. << 380 << 381 --quiet:: << 382 Don't print output, warnings or messages. This << 383 record below to only write data to the perf.da << 384 << 385 STAT RECORD 312 STAT RECORD 386 ----------- 313 ----------- 387 Stores stat data into perf data file. 314 Stores stat data into perf data file. 388 315 389 -o file:: 316 -o file:: 390 --output file:: 317 --output file:: 391 Output file name. 318 Output file name. 392 319 393 STAT REPORT 320 STAT REPORT 394 ----------- 321 ----------- 395 Reads and reports stat data from perf data fil 322 Reads and reports stat data from perf data file. 396 323 397 -i file:: 324 -i file:: 398 --input file:: 325 --input file:: 399 Input file name. 326 Input file name. 400 327 401 --per-socket:: 328 --per-socket:: 402 Aggregate counts per processor socket for syst 329 Aggregate counts per processor socket for system-wide mode measurements. 403 330 404 --per-die:: 331 --per-die:: 405 Aggregate counts per processor die for system- 332 Aggregate counts per processor die for system-wide mode measurements. 406 333 407 --per-cluster:: << 408 Aggregate counts perf processor cluster for sy << 409 << 410 --per-cache:: << 411 Aggregate counts per cache instance for system << 412 default, the aggregation happens for the cache << 413 in the system. To specify a particular level, << 414 alongside the option in the format [Ll][1-9][0 << 415 option "--per-cache=l3" or "--per-cache=L3" wi << 416 information at the boundary of the level 3 cac << 417 << 418 --per-core:: 334 --per-core:: 419 Aggregate counts per physical processor for sy 335 Aggregate counts per physical processor for system-wide mode measurements. 420 336 421 -M:: 337 -M:: 422 --metrics:: 338 --metrics:: 423 Print metrics or metricgroups specified in a c 339 Print metrics or metricgroups specified in a comma separated list. 424 For a group all metrics from the group are add 340 For a group all metrics from the group are added. 425 The events from the metrics are automatically 341 The events from the metrics are automatically measured. 426 See perf list output for the possible metrics !! 342 See perf list output for the possble metrics and metricgroups. 427 << 428 When threshold information is availabl << 429 color red is used to signify a metric << 430 while green shows it hasn't. The defau << 431 no threshold information was available << 432 couldn't be computed. << 433 343 434 -A:: 344 -A:: 435 --no-aggr:: 345 --no-aggr:: 436 --no-merge:: !! 346 Do not aggregate counts across all monitored CPUs. 437 Do not aggregate/merge counts across monitored << 438 << 439 When multiple events are created from a single << 440 stat will, by default, aggregate the event cou << 441 in a single row. This option disables that beh << 442 individual events and counts. << 443 << 444 Multiple events are created from a single even << 445 << 446 1. PID monitoring isn't requested and the syst << 447 CPU. For example, a system with 8 SMT threa << 448 opened on each thread and aggregation is pe << 449 << 450 2. Prefix or glob wildcard matching is used fo << 451 example, multiple memory controller PMUs ma << 452 suffix of _0, _1, etc. By default the event << 453 combined if the PMU is specified without th << 454 uncore_imc rather than uncore_imc_0. << 455 << 456 3. Aliases, which are listed immediately after << 457 by perf list, are used. << 458 << 459 --hybrid-merge:: << 460 Merge core event counts from all core PMUs. In << 461 systems by default each core PMU will report i << 462 separately. This option forces core PMU counts << 463 a behavior closer to having a single CPU type << 464 347 465 --topdown:: 348 --topdown:: 466 Print top-down metrics supported by the CPU. T !! 349 Print top down level 1 metrics if supported by the CPU. This allows to 467 bottle necks in the CPU pipeline for CPU bound !! 350 determine bottle necks in the CPU pipeline for CPU bound workloads, 468 the cycles consumed down into frontend bound, !! 351 by breaking the cycles consumed down into frontend bound, backend bound, 469 speculation and retiring. !! 352 bad speculation and retiring. 470 353 471 Frontend bound means that the CPU cannot fetch 354 Frontend bound means that the CPU cannot fetch and decode instructions fast 472 enough. Backend bound means that computation o 355 enough. Backend bound means that computation or memory access is the bottle 473 neck. Bad Speculation means that the CPU waste 356 neck. Bad Speculation means that the CPU wasted cycles due to branch 474 mispredictions and similar issues. Retiring me 357 mispredictions and similar issues. Retiring means that the CPU computed without 475 an apparently bottleneck. The bottleneck is on 358 an apparently bottleneck. The bottleneck is only the real bottleneck 476 if the workload is actually bound by the CPU a 359 if the workload is actually bound by the CPU and not by something else. 477 360 478 For best results it is usually a good idea to 361 For best results it is usually a good idea to use it with interval 479 mode like -I 1000, as the bottleneck of worklo 362 mode like -I 1000, as the bottleneck of workloads can change often. 480 363 481 This enables --metric-only, unless overridden << 482 << 483 The following restrictions only apply to older << 484 on newer CPUs (IceLake and later) TopDown can << 485 << 486 The top down metrics are collected per core in 364 The top down metrics are collected per core instead of per 487 CPU thread. Per core mode is automatically ena 365 CPU thread. Per core mode is automatically enabled 488 and -a (global monitoring) is needed, requirin 366 and -a (global monitoring) is needed, requiring root rights or 489 perf.perf_event_paranoid=-1. 367 perf.perf_event_paranoid=-1. 490 368 491 Topdown uses the full Performance Monitoring U 369 Topdown uses the full Performance Monitoring Unit, and needs 492 disabling of the NMI watchdog (as root): 370 disabling of the NMI watchdog (as root): 493 echo 0 > /proc/sys/kernel/nmi_watchdog 371 echo 0 > /proc/sys/kernel/nmi_watchdog 494 for best results. Otherwise the bottlenecks ma 372 for best results. Otherwise the bottlenecks may be inconsistent 495 on workload with changing phases. 373 on workload with changing phases. 496 374 >> 375 This enables --metric-only, unless overridden with --no-metric-only. >> 376 497 To interpret the results it is usually needed 377 To interpret the results it is usually needed to know on which 498 CPUs the workload runs on. If needed the CPUs 378 CPUs the workload runs on. If needed the CPUs can be forced using 499 taskset. 379 taskset. 500 380 501 --record-tpebs:: !! 381 --no-merge:: 502 Enable automatic sampling on Intel TPEBS retir !! 382 Do not merge results from same PMUs. 503 modifier). Without this option, perf would not !! 383 504 at runtime. Currently, a zero value is assigne !! 384 When multiple events are created from a single event specification, 505 this option is not set. The TPEBS hardware fea !! 385 stat will, by default, aggregate the event counts and show the result 506 Rapids microarchitecture. This option only exi !! 386 in a single row. This option disables that behavior and shows 507 Intel platforms with TPEBS feature. !! 387 the individual events and counts. 508 << 509 --td-level:: << 510 Print the top-down statistics that equal the i << 511 users to print the interested top-down metrics << 512 level 1 top-down metrics. << 513 << 514 As the higher levels gather more metrics and u << 515 will be less accurate. By convention a metric << 516 appending '_group' to it and this will increas << 517 gathering all metrics for a level. For example << 518 highlight 'tma_frontend_bound'. This metric ma << 519 'tma_frontend_bound_group' with << 520 'perf stat -M tma_frontend_bound_group...'. << 521 388 522 Error out if the input is higher than the supp !! 389 Multiple events are created from a single event specification when: >> 390 1. Prefix or glob matching is used for the PMU name. >> 391 2. Aliases, which are listed immediately after the Kernel PMU events >> 392 by perf list, are used. 523 393 524 --smi-cost:: 394 --smi-cost:: 525 Measure SMI cost if msr/aperf/ and msr/smi/ ev 395 Measure SMI cost if msr/aperf/ and msr/smi/ events are supported. 526 396 527 During the measurement, the /sys/device/cpu/fr 397 During the measurement, the /sys/device/cpu/freeze_on_smi will be set to 528 freeze core counters on SMI. 398 freeze core counters on SMI. 529 The aperf counter will not be effected by the 399 The aperf counter will not be effected by the setting. 530 The cost of SMI can be measured by (aperf - un 400 The cost of SMI can be measured by (aperf - unhalted core cycles). 531 401 532 In practice, the percentages of SMI cycles is 402 In practice, the percentages of SMI cycles is very useful for performance 533 oriented analysis. --metric_only will be appli 403 oriented analysis. --metric_only will be applied by default. 534 The output is SMI cycles%, equals to (aperf - 404 The output is SMI cycles%, equals to (aperf - unhalted core cycles) / aperf 535 405 536 Users who wants to get the actual value can ap 406 Users who wants to get the actual value can apply --no-metric-only. 537 407 538 --all-kernel:: 408 --all-kernel:: 539 Configure all used events to run in kernel spa 409 Configure all used events to run in kernel space. 540 410 541 --all-user:: 411 --all-user:: 542 Configure all used events to run in user space 412 Configure all used events to run in user space. 543 413 544 --percore-show-thread:: 414 --percore-show-thread:: 545 The event modifier "percore" has supported to 415 The event modifier "percore" has supported to sum up the event counts 546 for all hardware threads in a core and show th 416 for all hardware threads in a core and show the counts per core. 547 417 548 This option with event modifier "percore" enab 418 This option with event modifier "percore" enabled also sums up the event 549 counts for all hardware threads in a core but 419 counts for all hardware threads in a core but show the sum counts per 550 hardware thread. This is essentially a replace 420 hardware thread. This is essentially a replacement for the any bit and 551 convenient for post processing. 421 convenient for post processing. 552 422 553 --summary:: 423 --summary:: 554 Print summary for interval mode (-I). 424 Print summary for interval mode (-I). 555 425 556 --no-csv-summary:: << 557 Don't print 'summary' at the first column for << 558 This option must be used with -x and --summary << 559 << 560 This option can be enabled in perf config by s << 561 'stat.no-csv-summary'. << 562 << 563 $ perf config stat.no-csv-summary=true << 564 << 565 --cputype:: << 566 Only enable events on applying cpu with this t << 567 (e.g. core or atom)" << 568 << 569 EXAMPLES 426 EXAMPLES 570 -------- 427 -------- 571 428 572 $ perf stat \-- make !! 429 $ perf stat -- make 573 430 574 Performance counter stats for 'make': 431 Performance counter stats for 'make': 575 432 576 83723.452481 task-clock:u (msec) 433 83723.452481 task-clock:u (msec) # 1.004 CPUs utilized 577 0 context-switches:u 434 0 context-switches:u # 0.000 K/sec 578 0 cpu-migrations:u 435 0 cpu-migrations:u # 0.000 K/sec 579 3,228,188 page-faults:u 436 3,228,188 page-faults:u # 0.039 M/sec 580 229,570,665,834 cycles:u 437 229,570,665,834 cycles:u # 2.742 GHz 581 313,163,853,778 instructions:u 438 313,163,853,778 instructions:u # 1.36 insn per cycle 582 69,704,684,856 branches:u 439 69,704,684,856 branches:u # 832.559 M/sec 583 2,078,861,393 branch-misses:u 440 2,078,861,393 branch-misses:u # 2.98% of all branches 584 441 585 83.409183620 seconds time elapsed 442 83.409183620 seconds time elapsed 586 443 587 74.684747000 seconds user 444 74.684747000 seconds user 588 8.739217000 seconds sys 445 8.739217000 seconds sys 589 446 590 TIMINGS 447 TIMINGS 591 ------- 448 ------- 592 As displayed in the example above we can displ 449 As displayed in the example above we can display 3 types of timings. 593 We always display the time the counters were e 450 We always display the time the counters were enabled/alive: 594 451 595 83.409183620 seconds time elapsed 452 83.409183620 seconds time elapsed 596 453 597 For workload sessions we also display time the 454 For workload sessions we also display time the workloads spent in 598 user/system lands: 455 user/system lands: 599 456 600 74.684747000 seconds user 457 74.684747000 seconds user 601 8.739217000 seconds sys 458 8.739217000 seconds sys 602 459 603 Those times are the very same as displayed by 460 Those times are the very same as displayed by the 'time' tool. 604 461 605 CSV FORMAT 462 CSV FORMAT 606 ---------- 463 ---------- 607 464 608 With -x, perf stat is able to output a not-qui 465 With -x, perf stat is able to output a not-quite-CSV format output 609 Commas in the output are not put into "". To m 466 Commas in the output are not put into "". To make it easy to parse 610 it is recommended to use a different character 467 it is recommended to use a different character like -x \; 611 468 612 The fields are in this order: 469 The fields are in this order: 613 470 614 - optional usec time stamp in fraction 471 - optional usec time stamp in fractions of second (with -I xxx) 615 - optional CPU, core, or socket identi 472 - optional CPU, core, or socket identifier 616 - optional number of logical CPUs aggr 473 - optional number of logical CPUs aggregated 617 - counter value 474 - counter value 618 - unit of the counter value or empty 475 - unit of the counter value or empty 619 - event name 476 - event name 620 - run time of counter 477 - run time of counter 621 - percentage of measurement time the c 478 - percentage of measurement time the counter was running 622 - optional variance if multiple values 479 - optional variance if multiple values are collected with -r 623 - optional metric value 480 - optional metric value 624 - optional unit of metric 481 - optional unit of metric 625 482 626 Additional metrics may be printed with all ear 483 Additional metrics may be printed with all earlier fields being empty. 627 << 628 include::intel-hybrid.txt[] << 629 << 630 JSON FORMAT << 631 ----------- << 632 << 633 With -j, perf stat is able to print out a JSON << 634 that can be used for parsing. << 635 << 636 - timestamp : optional usec time stamp in frac << 637 - optional aggregate options: << 638 - core : core identifier (with << 639 - die : die identifier (with - << 640 - socket : socket identifier ( << 641 - node : node identifier (with << 642 - thread : thread identifier ( << 643 - counter-value : counter value << 644 - unit : unit of the counter value or empty << 645 - event : event name << 646 - variance : optional variance if multiple val << 647 - runtime : run time of counter << 648 - metric-value : optional metric value << 649 - metric-unit : optional unit of metric << 650 484 651 SEE ALSO 485 SEE ALSO 652 -------- 486 -------- 653 linkperf:perf-top[1], linkperf:perf-list[1] 487 linkperf:perf-top[1], linkperf:perf-list[1]
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.