1DBI::ProfileData(3) User Contributed Perl Documentation DBI::ProfileData(3)
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6 DBI::ProfileData - manipulate DBI::ProfileDumper data dumps
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9 The easiest way to use this module is through the dbiprof frontend (see
10 dbiprof for details):
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12 dbiprof --number 15 --sort count
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14 This module can also be used to roll your own profile analysis:
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16 # load data from dbi.prof
17 $prof = DBI::ProfileData->new(File => "dbi.prof");
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19 # get a count of the records (unique paths) in the data set
20 $count = $prof->count();
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22 # sort by longest overall time
23 $prof->sort(field => "longest");
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25 # sort by longest overall time, least to greatest
26 $prof->sort(field => "longest", reverse => 1);
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28 # exclude records with key2 eq 'disconnect'
29 $prof->exclude(key2 => 'disconnect');
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31 # exclude records with key1 matching /^UPDATE/i
32 $prof->exclude(key1 => qr/^UPDATE/i);
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34 # remove all records except those where key1 matches /^SELECT/i
35 $prof->match(key1 => qr/^SELECT/i);
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37 # produce a formatted report with the given number of items
38 $report = $prof->report(number => 10);
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40 # clone the profile data set
41 $clone = $prof->clone();
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43 # get access to hash of header values
44 $header = $prof->header();
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46 # get access to sorted array of nodes
47 $nodes = $prof->nodes();
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49 # format a single node in the same style as report()
50 $text = $prof->format($nodes->[0]);
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52 # get access to Data hash in DBI::Profile format
53 $Data = $prof->Data();
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56 This module offers the ability to read, manipulate and format
57 DBI::ProfileDumper profile data.
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59 Conceptually, a profile consists of a series of records, or nodes, each
60 of each has a set of statistics and set of keys. Each record must have
61 a unique set of keys, but there is no requirement that every record
62 have the same number of keys.
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65 The following methods are supported by DBI::ProfileData objects.
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67 $prof = DBI::ProfileData->new(File => "dbi.prof")
68 $prof = DBI::ProfileData->new(File => "dbi.prof", Filter => sub { ... })
69 $prof = DBI::ProfileData->new(Files => [ "dbi.prof.1", "dbi.prof.2" ])
70 Creates a new DBI::ProfileData object. Takes either a single file
71 through the File option or a list of Files in an array ref. If
72 multiple files are specified then the header data from the first file
73 is used.
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75 Files
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77 Reference to an array of file names to read.
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79 File
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81 Name of file to read. Takes precedence over "Files".
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83 DeleteFiles
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85 If true, the files are deleted after being read.
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87 Actually the files are renamed with a "deleteme" suffix before being
88 read, and then, after reading all the files, they're all deleted
89 together.
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91 The files are locked while being read which, combined with the rename,
92 makes it safe to 'consume' files that are still being generated by
93 DBI::ProfileDumper.
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95 Filter
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97 The "Filter" parameter can be used to supply a code reference that can
98 manipulate the profile data as it is being read. This is most useful
99 for editing SQL statements so that slightly different statements in the
100 raw data will be merged and aggregated in the loaded data. For example:
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102 Filter => sub {
103 my ($path_ref, $data_ref) = @_;
104 s/foo = '.*?'/foo = '...'/ for @$path_ref;
105 }
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107 Here's an example that performs some normalization on the SQL. It
108 converts all numbers to "N" and all quoted strings to "S". It can also
109 convert digits to N within names. Finally, it summarizes long "IN
110 (...)" clauses.
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112 It's aggressive and simplistic, but it's often sufficient, and serves
113 as an example that you can tailor to suit your own needs:
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115 Filter => sub {
116 my ($path_ref, $data_ref) = @_;
117 local $_ = $path_ref->[0]; # whichever element contains the SQL Statement
118 s/\b\d+\b/N/g; # 42 -> N
119 s/\b0x[0-9A-Fa-f]+\b/N/g; # 0xFE -> N
120 s/'.*?'/'S'/g; # single quoted strings (doesn't handle escapes)
121 s/".*?"/"S"/g; # double quoted strings (doesn't handle escapes)
122 # convert names like log_20001231 into log_NNNNNNNN, controlled by $opt{n}
123 s/([a-z_]+)(\d{$opt{n},})/$1.('N' x length($2))/ieg if $opt{n};
124 # abbreviate massive "in (...)" statements and similar
125 s!(([NS],){100,})!sprintf("$2,{repeated %d times}",length($1)/2)!eg;
126 }
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128 It's often better to perform this kinds of normalization in the DBI
129 while the data is being collected, to avoid too much memory being used
130 by storing profile data for many different SQL statement. See
131 DBI::Profile.
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133 $copy = $prof->clone();
134 Clone a profile data set creating a new object.
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136 $header = $prof->header();
137 Returns a reference to a hash of header values. These are the key
138 value pairs included in the header section of the DBI::ProfileDumper
139 data format. For example:
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141 $header = {
142 Path => [ '!Statement', '!MethodName' ],
143 Program => 't/42profile_data.t',
144 };
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146 Note that modifying this hash will modify the header data stored inside
147 the profile object.
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149 $nodes = $prof->nodes()
150 Returns a reference the sorted nodes array. Each element in the array
151 is a single record in the data set. The first seven elements are the
152 same as the elements provided by DBI::Profile. After that each key is
153 in a separate element. For example:
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155 $nodes = [
156 [
157 2, # 0, count
158 0.0312958955764771, # 1, total duration
159 0.000490069389343262, # 2, first duration
160 0.000176072120666504, # 3, shortest duration
161 0.00140702724456787, # 4, longest duration
162 1023115819.83019, # 5, time of first event
163 1023115819.86576, # 6, time of last event
164 'SELECT foo FROM bar' # 7, key1
165 'execute' # 8, key2
166 # 6+N, keyN
167 ],
168 # ...
169 ];
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171 Note that modifying this array will modify the node data stored inside
172 the profile object.
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174 $count = $prof->count()
175 Returns the number of items in the profile data set.
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177 $prof->sort(field => "field")
178 $prof->sort(field => "field", reverse => 1)
179 Sorts data by the given field. Available fields are:
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181 longest
182 total
183 count
184 shortest
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186 The default sort is greatest to smallest, which is the opposite of the
187 normal Perl meaning. This, however, matches the expected behavior of
188 the dbiprof frontend.
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190 $count = $prof->exclude(key2 => "disconnect")
191 $count = $prof->exclude(key2 => "disconnect", case_sensitive => 1)
192 $count = $prof->exclude(key1 => qr/^SELECT/i)
193 Removes records from the data set that match the given string or
194 regular expression. This method modifies the data in a permanent
195 fashion - use clone() first to maintain the original data after
196 exclude(). Returns the number of nodes left in the profile data set.
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198 $count = $prof->match(key2 => "disconnect")
199 $count = $prof->match(key2 => "disconnect", case_sensitive => 1)
200 $count = $prof->match(key1 => qr/^SELECT/i)
201 Removes records from the data set that do not match the given string or
202 regular expression. This method modifies the data in a permanent
203 fashion - use clone() first to maintain the original data after
204 match(). Returns the number of nodes left in the profile data set.
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206 $Data = $prof->Data()
207 Returns the same Data hash structure as seen in DBI::Profile. This
208 structure is not sorted. The nodes() structure probably makes more
209 sense for most analysis.
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211 $text = $prof->format($nodes->[0])
212 Formats a single node into a human-readable block of text.
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214 $text = $prof->report(number => 10)
215 Produces a report with the given number of items.
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218 Sam Tregar <sam@tregar.com>
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221 Copyright (C) 2002 Sam Tregar
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223 This program is free software; you can redistribute it and/or modify it
224 under the same terms as Perl 5 itself.
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228perl v5.28.1 2017-08-13 DBI::ProfileData(3)