p2p: Make HTTP downloads fail fast if using p2p to download
Failing fast when downloading via p2p is desirable because if we're
disconnected from the peer we're downloading from, chances are good
that it's not coming back. For example the peer could have gone to
sleep (user shutting the lid) or gone out of range. This is unlike the
non-p2p path where we can assume much better connectivity.
Also introduce new constants instead of hard-coded numbers and move
some existing constants to constants.h.
BUG=chromium:260426
TEST=Unit tests pass
Change-Id: Id2f1d0c60907caec06c4bdff3c70871d9f3eb20d
Reviewed-on: https://chromium-review.googlesource.com/64830
Reviewed-by: David Zeuthen <zeuthen@chromium.org>
Commit-Queue: David Zeuthen <zeuthen@chromium.org>
Tested-by: David Zeuthen <zeuthen@chromium.org>
diff --git a/constants.h b/constants.h
index f3e7450..5b0ba8c 100644
--- a/constants.h
+++ b/constants.h
@@ -116,6 +116,45 @@
// General constants
const int kNumBytesInOneMiB = 1024 * 1024;
+// Number of redirects allowed when downloading.
+const int kDownloadMaxRedirects = 10;
+
+// The minimum average speed (50 kB/sec) that downloads must sustain...
+//
+// This is set low because some devices may have very poor
+// connecticity and we want to make as much forward progress as
+// possible. For p2p this is high (50 kB/second) since we can assume
+// high bandwidth (same LAN) and we want to fail fast.
+const int kDownloadLowSpeedLimitBps = 1;
+const int kDownloadP2PLowSpeedLimitBps = 50 * 1000;
+
+// ... measured over this period.
+//
+// For non-official builds (e.g. typically built on a developer's
+// workstation and served via devserver) bump this since it takes time
+// for the workstation to generate the payload. For p2p, make this
+// relatively low since we want to fail fast.
+const int kDownloadLowSpeedTimeSeconds = 90;
+const int kDownloadDevModeLowSpeedTimeSeconds = 180;
+const int kDownloadP2PLowSpeedTimeSeconds = 30;
+
+// The maximum amount of HTTP server reconnect attempts.
+//
+// This is set high in order to maximize the attempt's chance of
+// succeeding. When using p2p, this is low in order to fail fast.
+const int kDownloadMaxRetryCount = 20;
+const int kDownloadMaxRetryCountOobeNotComplete = 3;
+const int kDownloadP2PMaxRetryCount = 3;
+
+// The connect timeout, in seconds.
+//
+// This is set high because some devices may have very poor
+// connectivity and we may be using HTTPS which involves complicated
+// multi-roundtrip setup. For p2p, this is set low because we can
+// the server is on the same LAN and we want to fail fast.
+const int kDownloadConnectTimeoutSeconds = 30;
+const int kDownloadP2PConnectTimeoutSeconds = 5;
+
} // namespace chromeos_update_engine
#endif // CHROMEOS_PLATFORM_UPDATE_ENGINE_CONSTANTS_H