Add trace_performance and trace_performance_since macros that print a
duration and an optional printf-formatted text to the file specified in
environment variable GIT_TRACE_PERFORMANCE.
These macros, in conjunction with getnanotime(), are intended to simplify
performance measurements from within the application (i.e. profiling via
manual instrumentation, rather than using an external profiling tool).
Unless enabled via GIT_TRACE_PERFORMANCE, these macros have no noticeable
impact on performance, so that test code for well known time killers may
be shipped in release builds. Alternatively, a developer could provide an
additional performance patch (not meant for master) that allows reviewers
to reproduce performance tests more easily, e.g. on other platforms or
using their own repositories.
Usage examples:
Simple use case (measure one code section):
uint64_t start = getnanotime();
/* code section to measure */
trace_performance_since(start, "foobar");
Complex use case (measure repetitive code sections):
uint64_t t = 0;
for (;;) {
/* ignore */
t -= getnanotime();
/* code section to measure */
t += getnanotime();
/* ignore */
}
trace_performance(t, "frotz");
Signed-off-by: Karsten Blees <blees@dcon.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
////////////////////////////////////////////////////////////////
Git - the stupid content tracker
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- random three-letter combination that is pronounceable, and not
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mispronunciation of "get" may or may not be relevant.
- stupid. contemptible and despicable. simple. Take your pick from the
dictionary of slang.
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Please read the file INSTALL for installation instructions.
See Documentation/gittutorial.txt to get started, then see
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If git has been correctly installed, then the tutorial can also be
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