bootstat: Differentiate system update boot times.
Bug: 27454343
Change-Id: Idb2e6f55ad7dda546a486954201619bb73cee6b0
diff --git a/bootstat/bootstat.cpp b/bootstat/bootstat.cpp
index b819797..976ba66 100644
--- a/bootstat/bootstat.cpp
+++ b/bootstat/bootstat.cpp
@@ -176,13 +176,41 @@
return kUnknownBootReason;
}
+// Returns the appropriate metric key prefix for the boot_complete metric such
+// that boot metrics after a system update are labeled as ota_boot_complete;
+// otherwise, they are labeled as boot_complete. This method encapsulates the
+// bookkeeping required to track when a system update has occurred by storing
+// the UTC timestamp of the system build date and comparing against the current
+// system build date.
+std::string CalculateBootCompletePrefix() {
+ static const std::string kBuildDateKey = "build_date";
+ std::string boot_complete_prefix = "boot_complete";
+
+ std::string build_date_str = GetProperty("ro.build.date.utc");
+ int32_t build_date = std::stoi(build_date_str);
+
+ BootEventRecordStore boot_event_store;
+ BootEventRecordStore::BootEventRecord record;
+ if (!boot_event_store.GetBootEvent(kBuildDateKey, &record) ||
+ build_date != record.second) {
+ boot_complete_prefix = "ota_" + boot_complete_prefix;
+ boot_event_store.AddBootEventWithValue(kBuildDateKey, build_date);
+ }
+
+ return boot_complete_prefix;
+}
+
// Records several metrics related to the time it takes to boot the device,
// including disambiguating boot time on encrypted or non-encrypted devices.
void RecordBootComplete() {
BootEventRecordStore boot_event_store;
+ BootEventRecordStore::BootEventRecord record;
time_t uptime = bootstat::ParseUptime();
- BootEventRecordStore::BootEventRecord record;
+ // The boot_complete metric has two variants: boot_complete and
+ // ota_boot_complete. The latter signifies that the device is booting after
+ // a system update.
+ std::string boot_complete_prefix = CalculateBootCompletePrefix();
// post_decrypt_time_elapsed is only logged on encrypted devices.
if (boot_event_store.GetBootEvent("post_decrypt_time_elapsed", &record)) {
@@ -193,18 +221,18 @@
// Subtract the decryption time to normalize the boot cycle timing.
time_t boot_complete = uptime - record.second;
- boot_event_store.AddBootEventWithValue("boot_complete_post_decrypt",
+ boot_event_store.AddBootEventWithValue(boot_complete_prefix + "_post_decrypt",
boot_complete);
} else {
- boot_event_store.AddBootEventWithValue("boot_complete_no_encryption",
+ boot_event_store.AddBootEventWithValue(boot_complete_prefix + "_no_encryption",
uptime);
}
// Record the total time from device startup to boot complete, regardless of
// encryption state.
- boot_event_store.AddBootEventWithValue("boot_complete", uptime);
+ boot_event_store.AddBootEventWithValue(boot_complete_prefix, uptime);
}
// Records the boot_reason metric by querying the ro.boot.bootreason system