main/dropbear-dbclient: Poor transfer rate compared to OpenSSH
When transfering large files over ssh using dropbear-dblient, I noticed a poor transfer rate compared to using openssh-client. In numbers, I only reached 200 MBit/s on a 1 GBit/s ethernet connection.
When running with valgrind/callgrind, I saw that dbclient uses ~ 70% of its runtime calling zlib (so compressing packets). My CPU is fairly recent, so the performane loss is not due to poor cpu performance.
When building db_client locally with ./configure --disable-zlib I reach ~900 MBit/s transfer rate