set default grpc values

[inolddays]

1.set grpc_keepalive_time to 10 seconds
2.set grpc_keepalive_timeout to 10 seconds
These settings will help to avoid the situation which query will hang there when pod or Bare metal is broken.

Signed-off-by: JohnnyThree whereshallyoube@gmail.com

[morgo]

This was previously reviewed here: #5478 -- we are good to merge.

[rafael]

Unfortunately this introduces a somewhat odd behavior. Not sure if we should consider it a bug, but with these defaults for idle connections, we will be closing them in an incorrect way due to ping strikes. This is because, the defaults from this PR are not compatible with the defaults here.

To make this clear with an example, the current settings of (grpc_keepalive_time=10s, grpc_keepalive_timeout=10s, grpc_server_keepalive_enforcement_policy_min_time=5min) will result in the following behavior:

• Client will try to send 6 pings in the first minute.
• Server will close that connection because the client is not respecting the keepalive enforcement policy.

I wonder what is the best approach here?

• Revert this change and think about better defaults ?
• Set up grpc_server_keepalive_enforcement_policy_min_time to 10 seconds as well?