metrics: Document uploader functionality
Metrics uploader can be activated with the metrics_uploader use flag, update
README to reflect that.
Also fix the section about activating metrics.
BUG=None
TEST=None
Change-Id: I2c6d0abe6536eb419c5b49f149b6d3f097670325
Reviewed-on: https://chromium-review.googlesource.com/216631
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Tested-by: Bertrand Simonnet <bsimonnet@chromium.org>
Commit-Queue: Bertrand Simonnet <bsimonnet@chromium.org>
diff --git a/metrics/README b/metrics/README
index 2ecec5f..6150dc7 100644
--- a/metrics/README
+++ b/metrics/README
@@ -3,8 +3,11 @@
found in the LICENSE file.
The Chrome OS "metrics" package contains utilities for client-side user metric
-collection. The collected data is sent to Chrome for transport to the UMA
-server.
+collection.
+When Chrome is installed, Chrome will take care of aggregating and uploading the
+metrics to the UMA server.
+When Chrome is not installed (embedded build) and the metrics_uploader USE flag
+is set, metrics_daemon will aggregate and upload the metrics itself.
================================================================================
@@ -36,8 +39,8 @@
For more information on the C API see c_metrics_library.h.
- Samples are sent to Chrome only if the "/home/chronos/Consent To Send Stats"
- file exists (see the AreMetricsEnabled API method). Normally, this file is
- created when the user opts into metrics collection.
+ file exists or the metrics are declared enabled in the policy file (see the
+ AreMetricsEnabled API method).
- On the target platform, shortly after the sample is sent, it should be visible
in Chrome through "about:histograms".