Here's the end of the output:
...updated 432 targets...
# Starting tests ("/home/tomkent/teeks99-03/a/tools_bb/src/engine/bin.linuxx86_64/bjam" "-sBOOST_BUILD_PATH=/home/tomkent/teeks99-03/a:/home/tomkent/teeks99-03/a/tools_bb/src" "-sBOOST_ROOT=/home/tomkent/teeks99-03/a/boost_root" "--boost=/home/tomkent/teeks99-03/a/boost_root" "--boost-build=/home/tomkent/teeks99-03/a/tools_bb/src" "--debug-configuration" -l300 toolset=gcc-4.4 -d2 preserve-test-targets=off --dump-tests -j2 -m64 "--build-dir=/home/tomkent/teeks99-03/a/results" >>"/home/tomkent/teeks99-03/a/results/bjam.log" 2>&1)...
# Running Boost.Build tests
# Using bjam binary in '/home/tomkent/teeks99-03/a/tools_bb/src/engine/bin.linuxx86_64'
# Getting test case results out of "/home/tomkent/teeks99-03/a/results/bjam.log"...
boost_root: /home/tomkent/teeks99-03/a/boost_root
locate_root: /home/tomkent/teeks99-03/a/results
*****Warning - missing test path: boost-test(RUN) "timer/inspect" ["always_show_run_output"] :
(Usually occurs when bjam doesn't know how to make a target)
At this point, the everything has stopped and the run doesn't progress (or timeout!), so it blocks the next runner from starting.