1perf-trace(1) 2============= 3 4NAME 5---- 6perf-trace - strace inspired tool 7 8SYNOPSIS 9-------- 10[verse] 11'perf trace' 12'perf trace record' 13 14DESCRIPTION 15----------- 16This command will show the events associated with the target, initially 17syscalls, but other system events like pagefaults, task lifetime events, 18scheduling events, etc. 19 20This is a live mode tool in addition to working with perf.data files like 21the other perf tools. Files can be generated using the 'perf record' command 22but the session needs to include the raw_syscalls events (-e 'raw_syscalls:*'). 23Alernatively, the 'perf trace record' can be used as a shortcut to 24automatically include the raw_syscalls events when writing events to a file. 25 26The following options apply to perf trace; options to perf trace record are 27found in the perf record man page. 28 29OPTIONS 30------- 31 32-a:: 33--all-cpus:: 34 System-wide collection from all CPUs. 35 36-e:: 37--expr:: 38 List of events to show, currently only syscall names. 39 Prefixing with ! shows all syscalls but the ones specified. You may 40 need to escape it. 41 42-o:: 43--output=:: 44 Output file name. 45 46-p:: 47--pid=:: 48 Record events on existing process ID (comma separated list). 49 50-t:: 51--tid=:: 52 Record events on existing thread ID (comma separated list). 53 54-u:: 55--uid=:: 56 Record events in threads owned by uid. Name or number. 57 58-v:: 59--verbose=:: 60 Verbosity level. 61 62-i:: 63--no-inherit:: 64 Child tasks do not inherit counters. 65 66-m:: 67--mmap-pages=:: 68 Number of mmap data pages (must be a power of two) or size 69 specification with appended unit character - B/K/M/G. The 70 size is rounded up to have nearest pages power of two value. 71 72-C:: 73--cpu:: 74Collect samples only on the list of CPUs provided. Multiple CPUs can be provided as a 75comma-separated list with no space: 0,1. Ranges of CPUs are specified with -: 0-2. 76In per-thread mode with inheritance mode on (default), Events are captured only when 77the thread executes on the designated CPUs. Default is to monitor all CPUs. 78 79--duration: 80 Show only events that had a duration greater than N.M ms. 81 82--sched: 83 Accrue thread runtime and provide a summary at the end of the session. 84 85-i 86--input 87 Process events from a given perf data file. 88 89-T 90--time 91 Print full timestamp rather time relative to first sample. 92 93--comm:: 94 Show process COMM right beside its ID, on by default, disable with --no-comm. 95 96-s:: 97--summary:: 98 Show only a summary of syscalls by thread with min, max, and average times 99 (in msec) and relative stddev. 100 101-S:: 102--with-summary:: 103 Show all syscalls followed by a summary by thread with min, max, and 104 average times (in msec) and relative stddev. 105 106--tool_stats:: 107 Show tool stats such as number of times fd->pathname was discovered thru 108 hooking the open syscall return + vfs_getname or via reading /proc/pid/fd, etc. 109 110-F=[all|min|maj]:: 111--pf=[all|min|maj]:: 112 Trace pagefaults. Optionally, you can specify whether you want minor, 113 major or all pagefaults. Default value is maj. 114 115--syscalls:: 116 Trace system calls. This options is enabled by default. 117 118PAGEFAULTS 119---------- 120 121When tracing pagefaults, the format of the trace is as follows: 122 123<min|maj>fault [<ip.symbol>+<ip.offset>] => <addr.dso@addr.offset> (<map type><addr level>). 124 125- min/maj indicates whether fault event is minor or major; 126- ip.symbol shows symbol for instruction pointer (the code that generated the 127 fault); if no debug symbols available, perf trace will print raw IP; 128- addr.dso shows DSO for the faulted address; 129- map type is either 'd' for non-executable maps or 'x' for executable maps; 130- addr level is either 'k' for kernel dso or '.' for user dso. 131 132For symbols resolution you may need to install debugging symbols. 133 134Please be aware that duration is currently always 0 and doesn't reflect actual 135time it took for fault to be handled! 136 137When --verbose specified, perf trace tries to print all available information 138for both IP and fault address in the form of dso@symbol+offset. 139 140EXAMPLES 141-------- 142 143Trace only major pagefaults: 144 145 $ perf trace --no-syscalls -F 146 147Trace syscalls, major and minor pagefaults: 148 149 $ perf trace -F all 150 151 1416.547 ( 0.000 ms): python/20235 majfault [CRYPTO_push_info_+0x0] => /lib/x86_64-linux-gnu/libcrypto.so.1.0.0@0x61be0 (x.) 152 153 As you can see, there was major pagefault in python process, from 154 CRYPTO_push_info_ routine which faulted somewhere in libcrypto.so. 155 156SEE ALSO 157-------- 158linkperf:perf-record[1], linkperf:perf-script[1] 159