1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
|
/*
* Oracle Linux DTrace.
* Copyright (c) 2025, Oracle and/or its affiliates. All rights reserved.
* Licensed under the Universal Permissive License v 1.0 as shown at
* http://oss.oracle.com/licenses/upl.
*/
/*
* NAME
* readsizes.d - show the distribution of bytes read when running find
*
* SYNOPSIS
* sudo dtrace -s readsizes.d
*
* DESCRIPTION
* Trace the calls to read() and use a predicate to only select those
* calls executed as part of executing the find command. For such
* calls, show the distribution of the sizes.
*
* NOTES
* - The script needs to be terminated with ctrl-C. In case the
* script is running in the background, get it to run in the
* foreground first by using the fg command and then use ctrl-C
* to terminate the process. Otherwise, typing in ctrl-C will do.
*
* - The results are stored in an aggregation called dist with
* the string "find" as the key.
*
* - The results of an aggregation are automatically printed when
* the tracing terminates.
*/
/*
* A predicate is used to guarantee that the clause for the read:entry
* probe is only executed in case the call to read() was issued by the
* find command.
*
* The quantize() function is used to show the distribution of the sizes
* read, or attempted to be read, by the read() call. This value is
* passed to the syscall function and to the D probe in arg2.
*/
syscall::read:entry
/execname == "find"/
{
@dist["find"] = quantize(arg2);
}
|
