| Arnaldo Carvalho de Melo | 86a9eee | 2009-12-14 20:09:31 -0200 | [diff] [blame] | 1 | perf-diff(1) |
| Arnaldo Carvalho de Melo | 4778e0e | 2010-05-05 11:23:27 -0300 | [diff] [blame] | 2 | ============ |
| Arnaldo Carvalho de Melo | 86a9eee | 2009-12-14 20:09:31 -0200 | [diff] [blame] | 3 | |
| 4 | NAME |
| 5 | ---- |
| Ingo Molnar | d30531c | 2009-12-15 10:24:08 +0100 | [diff] [blame] | 6 | perf-diff - Read two perf.data files and display the differential profile |
| Arnaldo Carvalho de Melo | 86a9eee | 2009-12-14 20:09:31 -0200 | [diff] [blame] | 7 | |
| 8 | SYNOPSIS |
| 9 | -------- |
| 10 | [verse] |
| 11 | 'perf diff' [oldfile] [newfile] |
| 12 | |
| 13 | DESCRIPTION |
| 14 | ----------- |
| Ingo Molnar | d30531c | 2009-12-15 10:24:08 +0100 | [diff] [blame] | 15 | This command displays the performance difference amongst two perf.data files |
| Arnaldo Carvalho de Melo | 86a9eee | 2009-12-14 20:09:31 -0200 | [diff] [blame] | 16 | captured via perf record. |
| 17 | |
| 18 | If no parameters are passed it will assume perf.data.old and perf.data. |
| 19 | |
| Jiri Olsa | 863e451 | 2012-09-06 17:46:55 +0200 | [diff] [blame] | 20 | The differential profile is displayed only for events matching both |
| 21 | specified perf.data files. |
| 22 | |
| Arnaldo Carvalho de Melo | 86a9eee | 2009-12-14 20:09:31 -0200 | [diff] [blame] | 23 | OPTIONS |
| 24 | ------- |
| Shawn Bohrer | 5ea4f85 | 2010-11-30 19:57:12 -0600 | [diff] [blame] | 25 | -M:: |
| 26 | --displacement:: |
| 27 | Show position displacement relative to baseline. |
| 28 | |
| 29 | -D:: |
| 30 | --dump-raw-trace:: |
| 31 | Dump raw trace in ASCII. |
| 32 | |
| 33 | -m:: |
| 34 | --modules:: |
| 35 | Load module symbols. WARNING: use only with -k and LIVE kernel |
| 36 | |
| Arnaldo Carvalho de Melo | c351c28 | 2009-12-16 13:49:27 -0200 | [diff] [blame] | 37 | -d:: |
| 38 | --dsos=:: |
| 39 | Only consider symbols in these dsos. CSV that understands |
| 40 | file://filename entries. |
| 41 | |
| 42 | -C:: |
| 43 | --comms=:: |
| 44 | Only consider symbols in these comms. CSV that understands |
| 45 | file://filename entries. |
| 46 | |
| 47 | -S:: |
| 48 | --symbols=:: |
| 49 | Only consider these symbols. CSV that understands |
| 50 | file://filename entries. |
| 51 | |
| 52 | -s:: |
| 53 | --sort=:: |
| 54 | Sort by key(s): pid, comm, dso, symbol. |
| 55 | |
| 56 | -t:: |
| 57 | --field-separator=:: |
| 58 | |
| 59 | Use a special separator character and don't pad with spaces, replacing |
| Shawn Bohrer | 5ea4f85 | 2010-11-30 19:57:12 -0600 | [diff] [blame] | 60 | all occurrences of this separator in symbol names (and other output) |
| Arnaldo Carvalho de Melo | c351c28 | 2009-12-16 13:49:27 -0200 | [diff] [blame] | 61 | with a '.' character, that thus it's the only non valid separator. |
| 62 | |
| Arnaldo Carvalho de Melo | 86a9eee | 2009-12-14 20:09:31 -0200 | [diff] [blame] | 63 | -v:: |
| 64 | --verbose:: |
| Ingo Molnar | d30531c | 2009-12-15 10:24:08 +0100 | [diff] [blame] | 65 | Be verbose, for instance, show the raw counts in addition to the |
| Arnaldo Carvalho de Melo | 86a9eee | 2009-12-14 20:09:31 -0200 | [diff] [blame] | 66 | diff. |
| Arnaldo Carvalho de Melo | cdccc69 | 2009-12-15 11:01:22 -0200 | [diff] [blame] | 67 | |
| Shawn Bohrer | 5ea4f85 | 2010-11-30 19:57:12 -0600 | [diff] [blame] | 68 | -f:: |
| 69 | --force:: |
| 70 | Don't complain, do it. |
| 71 | |
| David Ahern | ec5761e | 2010-12-09 13:27:07 -0700 | [diff] [blame] | 72 | --symfs=<directory>:: |
| 73 | Look for files with symbols relative to this directory. |
| Shawn Bohrer | 5ea4f85 | 2010-11-30 19:57:12 -0600 | [diff] [blame] | 74 | |
| Jiri Olsa | a06d143 | 2012-10-05 16:44:40 +0200 | [diff] [blame] | 75 | -b:: |
| 76 | --baseline-only:: |
| 77 | Show only items with match in baseline. |
| 78 | |
| Jiri Olsa | 7aaf6b3 | 2012-10-05 16:44:41 +0200 | [diff] [blame] | 79 | -c:: |
| 80 | --compute:: |
| Jiri Olsa | 81d5f95 | 2012-10-05 16:44:43 +0200 | [diff] [blame^] | 81 | Differential computation selection - delta,ratio,wdiff (default is delta). |
| Jiri Olsa | 96c47f1 | 2012-10-05 16:44:42 +0200 | [diff] [blame] | 82 | If '+' is specified as a first character, the output is sorted based |
| 83 | on the computation results. |
| Jiri Olsa | 7aaf6b3 | 2012-10-05 16:44:41 +0200 | [diff] [blame] | 84 | See COMPARISON METHODS section for more info. |
| 85 | |
| 86 | COMPARISON METHODS |
| 87 | ------------------ |
| 88 | delta |
| 89 | ~~~~~ |
| 90 | If specified the 'Delta' column is displayed with value 'd' computed as: |
| 91 | |
| 92 | d = A->period_percent - B->period_percent |
| 93 | |
| 94 | with: |
| 95 | - A/B being matching hist entry from first/second file specified |
| 96 | (or perf.data/perf.data.old) respectively. |
| 97 | |
| 98 | - period_percent being the % of the hist entry period value within |
| 99 | single data file |
| 100 | |
| 101 | ratio |
| 102 | ~~~~~ |
| 103 | If specified the 'Ratio' column is displayed with value 'r' computed as: |
| 104 | |
| 105 | r = A->period / B->period |
| 106 | |
| 107 | with: |
| 108 | - A/B being matching hist entry from first/second file specified |
| 109 | (or perf.data/perf.data.old) respectively. |
| 110 | |
| 111 | - period being the hist entry period value |
| 112 | |
| Jiri Olsa | 81d5f95 | 2012-10-05 16:44:43 +0200 | [diff] [blame^] | 113 | wdiff |
| 114 | ~~~~~ |
| 115 | If specified the 'Weighted diff' column is displayed with value 'd' computed as: |
| 116 | |
| 117 | d = B->period * WEIGHT-A - A->period * WEIGHT-B |
| 118 | |
| 119 | - A/B being matching hist entry from first/second file specified |
| 120 | (or perf.data/perf.data.old) respectively. |
| 121 | |
| 122 | - period being the hist entry period value |
| 123 | |
| 124 | - WEIGHT-A/WEIGHT-B being user suplied weights in the the '-c' option |
| 125 | behind ':' separator like '-c wdiff:1,2'. |
| Jiri Olsa | 7aaf6b3 | 2012-10-05 16:44:41 +0200 | [diff] [blame] | 126 | |
| Arnaldo Carvalho de Melo | 86a9eee | 2009-12-14 20:09:31 -0200 | [diff] [blame] | 127 | SEE ALSO |
| 128 | -------- |
| 129 | linkperf:perf-record[1] |