From 32b6e8e19851418e2c6e8714c6bf8004d51ce26e Mon Sep 17 00:00:00 2001
From: Damien Elmes <gpg@ankiweb.net>
Date: Thu, 17 Dec 2020 12:03:24 +1000
Subject: [PATCH] document ANKI_PROFILE_CODE and add bazel command to run
 snakeviz

---
 docs/development.md | 2 ++
 pip/requirements.in | 1 +
 qt/BUILD.bazel      | 9 +++++++++
 qt/aqt/__init__.py  | 1 +
 qt/tools/profile.py | 8 ++++++++
 5 files changed, 21 insertions(+)
 create mode 100755 qt/tools/profile.py

diff --git a/docs/development.md b/docs/development.md
index 325e25dfd..2319322f1 100644
--- a/docs/development.md
+++ b/docs/development.md
@@ -210,6 +210,8 @@ If TRACESQL is set, all sql statements will be printed as they are executed.
 If LOGTERM is set before starting Anki, warnings and error messages that are normally placed
 in the collection2.log file will also be printed on stdout.
 
+If ANKI_PROFILE_CODE is set, Python profiling data will be written on exit.
+
 ## Cleaning
 
 Unlike the old Make system, a "clean build" should almost never be required
diff --git a/pip/requirements.in b/pip/requirements.in
index ebf4183de..aeb852182 100644
--- a/pip/requirements.in
+++ b/pip/requirements.in
@@ -17,6 +17,7 @@ pylint
 pytest
 requests[socks]
 send2trash
+snakeviz
 stringcase
 waitress
 fluent-syntax
diff --git a/qt/BUILD.bazel b/qt/BUILD.bazel
index e9900f562..c48586ba5 100644
--- a/qt/BUILD.bazel
+++ b/qt/BUILD.bazel
@@ -128,3 +128,12 @@ py_binary(
         "//qt/aqt:aqt_with_data",
     ],
 )
+
+py_binary(
+    name = "profile",
+    srcs = ["tools/profile.py"],
+    tags = ["manual"],
+    deps = [
+        requirement("snakeviz"),
+    ],
+)
diff --git a/qt/aqt/__init__.py b/qt/aqt/__init__.py
index 3516d95fd..37a580654 100644
--- a/qt/aqt/__init__.py
+++ b/qt/aqt/__init__.py
@@ -392,6 +392,7 @@ def write_profile_results():
     profiler.disable()
     profiler.dump_stats("anki.prof")
     print("profile stats written to anki.prof")
+    print("use 'bazel run qt:profile' to explore")
 
 
 def run():
diff --git a/qt/tools/profile.py b/qt/tools/profile.py
new file mode 100755
index 000000000..99b1376f4
--- /dev/null
+++ b/qt/tools/profile.py
@@ -0,0 +1,8 @@
+import sys, os
+import snakeviz
+
+from snakeviz.cli import main
+
+profile = os.path.join(os.environ["BUILD_WORKSPACE_DIRECTORY"], "anki.prof")
+sys.argv.append(profile)
+sys.exit(main())