vtune: initial notes

5 files changed, 90 insertions, 0 deletions

diff --git a/src/SUMMARY.md b/src/SUMMARY.md
index c1f7cca..29f4eee 100644
--- a/src/SUMMARY.md
+++ b/src/SUMMARY.md
@@ -53,6 +53,7 @@
     - [OProfile](./trace_profile/oprofile.md)
     - [callgrind](./trace_profile/callgrind.md)
     - [valgrind](./trace_profile/valgrind.md)
+    - [vtune](./trace_profile/vtune.md)
 
 - [Debug](./debug/README.md)
     - [gdb](./debug/gdb.md)
diff --git a/src/trace_profile/README.md b/src/trace_profile/README.md
index 35d3c5b..d9635dd 100644
--- a/src/trace_profile/README.md
+++ b/src/trace_profile/README.md
@@ -7,3 +7,4 @@
 - [OProfile](./oprofile.md)
 - [callgrind](./callgrind.md)
 - [valgrind](./valgrind.md)
+- [vtune](./vtune.md)
diff --git a/src/trace_profile/vtune.md b/src/trace_profile/vtune.md
new file mode 100644
index 0000000..022a652
--- /dev/null
+++ b/src/trace_profile/vtune.md
@@ -0,0 +1,45 @@
+# [vtune(1)][vtune]
+
+Vtune offers different analysis. Run `vtune -collect help` to list the
+availale analysis.
+
+## Profiling
+
+The following shows some common flows with the `hotspot` analsysis
+as an example.
+```
+# Launch and profile process.
+vtune -collect hotspots [opts] -- target [args]
+
+# Attach and profile running process.
+vtune -collect hotspots [opts] -target-pid <pid>
+```
+Some common options are the following.
+```
+-r <dir>           output directory for the profile
+-no-follow-child   dont attach to to child processes (default is to follow)
+-start-paused      start with paused profiling
+```
+
+## Analyze
+```
+vtune-gui <dir>
+```
+
+## Programmatically control sampling
+Vtune offers an API to *resume* and *pause* the profile collection from within
+the profilee itself.  This can be helpful if either only a certain phase should
+be profiled or some phase should be skipped.
+
+The following gives an example where only one phase in the program is profiled.
+The program makes calls to the vtune API to resume and pause the collection,
+while vtune is invoked with `-start-paused` to pause profiling initially.
+```c
+{{#include vtune/main.c::16}}
+```
+The makefile gives an example how to build and profile the application.
+```makefile
+{{#include vtune/Makefile::7}}
+```
+
+[vtune]: https://www.intel.com/content/www/us/en/docs/vtune-profiler/user-guide
diff --git a/src/trace_profile/vtune/Makefile b/src/trace_profile/vtune/Makefile
new file mode 100644
index 0000000..694e453
--- /dev/null
+++ b/src/trace_profile/vtune/Makefile
@@ -0,0 +1,11 @@
+VTUNE ?= /opt/intel/oneapi/vtune/latest
+
+main: main.c
+	gcc -o $@ $^ -I$(VTUNE)/include -L$(VTUNE)/lib64 -littnotify
+
+vtune: main
+	$(VTUNE)/bin64/vtune -collect hotspots -start-paused -- ./main
+
+clean:
+	$(RM) main
+	$(RM) -r r*hs
diff --git a/src/trace_profile/vtune/main.c b/src/trace_profile/vtune/main.c
new file mode 100644
index 0000000..8c019d3
--- /dev/null
+++ b/src/trace_profile/vtune/main.c
@@ -0,0 +1,32 @@
+#include <ittnotify.h>
+
+void init();
+void compute();
+void shutdown();
+
+int main() {
+  init();
+
+  __itt_resume();
+  compute();
+  __itt_pause();
+
+  shutdown();
+  return 0;
+}
+
+//
+
+#include <unistd.h>
+
+void init() {
+  sleep(1);
+}
+
+void compute() {
+  sleep(1);
+}
+
+void shutdown() {
+  sleep(1);
+}