We had freezes/timeouts only when the disk filled up, other than that it was pretty good. Simply writing the data to HDFS is a lot cheaper operation than commi

We had freezes/timeouts only when the disk filled up, other than that it was pretty good. Simply writing the data to HDFS is a lot cheaper operation than committing the data to a local database, so in practice it was a lower latency than having a "real" standby server that committed logs to disk. (We saw about a 3x TPS gain over a dedicated standby in synchronous mode.) Also the way I see it, turning on 'synchronous_standby_names' was a nice added safety guarantee, in practice leaving the hdfs receiver asynchronous would be a reasonable alternative if you're confident things will work as you expect.