Change the default interval to 5 seconds

Author: y-zeng

doc/environment_variables.md

@@ -121,7 +121,7 @@ some configuration as environment variables that can be set.
   - ares - a DNS resolver based around the c-ares library
 
 * GRPC_CLIENT_CHANNEL_BACKUP_POLL_INTERVAL_MS
-  Default: 500
+  Default: 5000
   Declares the interval between two backup polls on client channels. These polls
   are run in the timer thread so that gRPC can process connection failures while
   there is no active polling thread. They help reconnect disconnected client

src/core/ext/filters/client_channel/backup_poller.cc

@@ -31,7 +31,7 @@
 #include "src/core/lib/surface/channel.h"
 #include "src/core/lib/surface/completion_queue.h"
 
-#define DEFAULT_POLL_INTERVAL_MS 500
+#define DEFAULT_POLL_INTERVAL_MS 5000
 
 typedef struct backup_poller {
   grpc_timer polling_timer;

test/cpp/end2end/async_end2end_test.cc

@@ -461,6 +461,7 @@ TEST_P(AsyncEnd2endTest, ReconnectChannel) {
   if (GetParam().inproc) {
     return;
   }
+  gpr_setenv("GRPC_CLIENT_CHANNEL_BACKUP_POLL_INTERVAL_MS", "200");
   int poller_slowdown_factor = 1;
   // It needs 2 pollset_works to reconnect the channel with polling engine
   // "poll"
@@ -478,12 +479,12 @@ TEST_P(AsyncEnd2endTest, ReconnectChannel) {
   while (cq_->Next(&ignored_tag, &ignored_ok))
     ;
   BuildAndStartServer();
-  // It needs more than kConnectivityCheckIntervalMsec time to reconnect the
-  // channel.
+  // It needs more than GRPC_CLIENT_CHANNEL_BACKUP_POLL_INTERVAL_MS time to
+  // reconnect the channel.
   gpr_sleep_until(gpr_time_add(
       gpr_now(GPR_CLOCK_REALTIME),
       gpr_time_from_millis(
-          600 * poller_slowdown_factor * grpc_test_slowdown_factor(),
+          300 * poller_slowdown_factor * grpc_test_slowdown_factor(),
           GPR_TIMESPAN)));
   SendRpc(1);
 }

test/cpp/end2end/end2end_test.cc

@@ -706,6 +706,7 @@ TEST_P(End2endTest, ReconnectChannel) {
   if (GetParam().inproc) {
     return;
   }
+  gpr_setenv("GRPC_CLIENT_CHANNEL_BACKUP_POLL_INTERVAL_MS", "200");
   int poller_slowdown_factor = 1;
   // It needs 2 pollset_works to reconnect the channel with polling engine
   // "poll"
@@ -717,12 +718,12 @@ TEST_P(End2endTest, ReconnectChannel) {
   ResetStub();
   SendRpc(stub_.get(), 1, false);
   RestartServer(std::shared_ptr<AuthMetadataProcessor>());
-  // It needs more than kConnectivityCheckIntervalMsec time to reconnect the
-  // channel.
+  // It needs more than GRPC_CLIENT_CHANNEL_BACKUP_POLL_INTERVAL_MS time to
+  // reconnect the channel.
   gpr_sleep_until(gpr_time_add(
       gpr_now(GPR_CLOCK_REALTIME),
       gpr_time_from_millis(
-          600 * poller_slowdown_factor * grpc_test_slowdown_factor(),
+          300 * poller_slowdown_factor * grpc_test_slowdown_factor(),
           GPR_TIMESPAN)));
   SendRpc(stub_.get(), 1, false);
 }