Revert "Improve connection failure robustness"
Revert the single thread update
This reverts commit ee971621f4a5c62b0d2301f2dd661c3c128abf1f.
and also :
08d45bf8c50436540dcda19dcb11b2da70d31694
4a3e0169a3197b476b448a83ec1ac67467c472f0
902beebfa64cd50a45d9b08290a13794d3dca9bb