2777: rbssh is very slow

krzyszto********@blstre****** (Google Code) (Is this you? Claim this profile.)
I have working instance of Reviewboard 1.6.13. Everything works except connecting via rbssh i very slow.

When I'm creating new review request than I have to wait long time.
In auth.log I see that rbssh is opening and closing ssh sessions - about 20 of them.
rbssh reviewboard@hostname runs about 40seconds
ssh reviewboard@hostname runs in 1sec.
The authentication is made with keys.
david
#1 david
  • +Component-SSH
#2 vladr

Yes, rbssh is a disaster. FWIW, replacing /usr/bin/rbssh with the following native wrapper yielded a 5x speed improvement:

!/bin/sh

EXTRA_OPTS="-o UserKnownHostsFile=$HOME/.ssh/known_hosts -o ForwardX11=no -o LogLevel=ERROR"
for k in $HOME/.ssh/id_{dsa,rsa} ; do
test -e "$k" && EXTRA_OPTS="$EXTRA_OPTS -i $k"
done

exec /usr/bin/ssh $EXTRA_OPTS "$@"

#3 vladr

Replace the contents of /usr/bin/rbssh with the following:

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#!/bin/sh
EXTRA_OPTS="-o UserKnownHostsFile=$HOME/.ssh/known_hosts -o ForwardX11=no -o LogLevel=ERROR"
# see https://en.wikibooks.org/wiki/OpenSSH/Cookbook/Multiplexing
EXTRA_OPTS="-o ControlPath=/tmp/master-%r@%h:%p -o ControlMaster=auto -o ControlPersist=10m $EXTRA_OPTS"
for k in $HOME/.ssh/id_{dsa,rsa} ; do
  test -e "$k" && EXTRA_OPTS="$EXTRA_OPTS -i $k"
done
exec /usr/bin/ssh $EXTRA_OPTS "$@"

Using native ssh was about 5x faster than the default Python rbssh implementation. Moreover, using the connection multiplexing feature of ssh further sped up things another 5x or so.