Initial pass at storage benchmarks.
Now that we're offering to store private app data on adopted storage
devices, the performance of those devices is much more important to
overall user experience.
To help set user expectations, this change offers to execute a
real-world benchmark on a storage device, returning a metric that can
be used to compare internal and external storage. The benchmark is
generated from the strace-instrumented storage access patterns of
typical apps.
A typical device completes the benchmark in under two seconds on
internal storage, a UHS-3 SD card is even faster (!), but a very slow
Class 4 SD card takes about 30 seconds to complete, giving us a clear
signal.
The measured benchmark numbers are logged along with information
about the storage device, such as manufacturer, model, etc. Card
serial numbers are scrubbed from output.
Bug: 21172095
Change-Id: I9b2713dafdfdfcf5d97bf1bc21841f39409a7e54
diff --git a/Benchmark.cpp b/Benchmark.cpp
new file mode 100644
index 0000000..077a9fa
--- /dev/null
+++ b/Benchmark.cpp
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Benchmark.h"
+#include "BenchmarkGen.h"
+#include "VolumeManager.h"
+#include "ResponseCode.h"
+
+#include <base/file.h>
+#include <base/logging.h>
+#include <cutils/iosched_policy.h>
+
+#include <sys/time.h>
+#include <sys/resource.h>
+
+using android::base::ReadFileToString;
+using android::base::WriteStringToFile;
+
+namespace android {
+namespace vold {
+
+static std::string simpleRead(const std::string& path) {
+ std::string tmp;
+ ReadFileToString(path, &tmp);
+ tmp.erase(tmp.find_last_not_of(" \n\r") + 1);
+ return tmp;
+}
+
+nsecs_t Benchmark(const std::string& path, const std::string& sysPath) {
+ errno = 0;
+ int orig_prio = getpriority(PRIO_PROCESS, 0);
+ if (errno != 0) {
+ PLOG(ERROR) << "Failed to getpriority";
+ return -1;
+ }
+ if (setpriority(PRIO_PROCESS, 0, -10) != 0) {
+ PLOG(ERROR) << "Failed to setpriority";
+ return -1;
+ }
+
+ IoSchedClass orig_clazz = IoSchedClass_NONE;
+ int orig_ioprio = 0;
+ if (android_get_ioprio(0, &orig_clazz, &orig_ioprio)) {
+ PLOG(ERROR) << "Failed to android_get_ioprio";
+ return -1;
+ }
+ if (android_set_ioprio(0, IoSchedClass_RT, 0)) {
+ PLOG(ERROR) << "Failed to android_set_ioprio";
+ return -1;
+ }
+
+ char orig_cwd[PATH_MAX];
+ if (getcwd(orig_cwd, PATH_MAX) == NULL) {
+ PLOG(ERROR) << "Failed getcwd";
+ return -1;
+ }
+ if (chdir(path.c_str()) != 0) {
+ PLOG(ERROR) << "Failed chdir";
+ return -1;
+ }
+
+ LOG(INFO) << "Benchmarking " << path;
+ nsecs_t start = systemTime(SYSTEM_TIME_BOOTTIME);
+
+ BenchmarkCreate();
+ nsecs_t create = systemTime(SYSTEM_TIME_BOOTTIME);
+
+ if (!WriteStringToFile("3", "/proc/sys/vm/drop_caches")) {
+ PLOG(ERROR) << "Failed to drop_caches";
+ }
+ nsecs_t drop = systemTime(SYSTEM_TIME_BOOTTIME);
+
+ BenchmarkRun();
+ nsecs_t run = systemTime(SYSTEM_TIME_BOOTTIME);
+
+ BenchmarkDestroy();
+ nsecs_t destroy = systemTime(SYSTEM_TIME_BOOTTIME);
+
+ nsecs_t create_d = create - start;
+ nsecs_t drop_d = drop - create;
+ nsecs_t run_d = run - drop;
+ nsecs_t destroy_d = destroy - run;
+
+ LOG(INFO) << "create took " << nanoseconds_to_milliseconds(create_d) << "ms";
+ LOG(INFO) << "drop took " << nanoseconds_to_milliseconds(drop_d) << "ms";
+ LOG(INFO) << "run took " << nanoseconds_to_milliseconds(run_d) << "ms";
+ LOG(INFO) << "destroy took " << nanoseconds_to_milliseconds(destroy_d) << "ms";
+
+ std::string detail;
+ detail += "id=" + BenchmarkIdent()
+ + ",cr=" + std::to_string(create_d)
+ + ",dr=" + std::to_string(drop_d)
+ + ",ru=" + std::to_string(run_d)
+ + ",de=" + std::to_string(destroy_d)
+ + ",si=" + simpleRead(sysPath + "/size")
+ + ",ve=" + simpleRead(sysPath + "/device/vendor")
+ + ",mo=" + simpleRead(sysPath + "/device/model")
+ + ",csd=" + simpleRead(sysPath + "/device/csd")
+ + ",scr=" + simpleRead(sysPath + "/device/scr");
+
+ // Scrub CRC and serial number out of CID
+ std::string cid = simpleRead(sysPath + "/device/cid");
+ if (cid.length() == 32) {
+ cid.erase(32, 1);
+ cid.erase(18, 8);
+ detail += ",cid=" + cid;
+ }
+
+ VolumeManager::Instance()->getBroadcaster()->sendBroadcast(
+ ResponseCode::BenchmarkResult, detail.c_str(), false);
+
+ if (chdir(orig_cwd) != 0) {
+ PLOG(ERROR) << "Failed to chdir";
+ }
+ if (android_set_ioprio(0, orig_clazz, orig_ioprio)) {
+ PLOG(ERROR) << "Failed to android_set_ioprio";
+ }
+ if (setpriority(PRIO_PROCESS, 0, orig_prio) != 0) {
+ PLOG(ERROR) << "Failed to setpriority";
+ }
+ return run_d;
+}
+
+} // namespace vold
+} // namespace android