Each job with custom mercurial auto install, tries to install it multiple times (see [1] below). The configuration is also captured below [2].

[1]
tools/hudson.plugins.mercurial.MercurialInstallation/mercurial_linux_home_27/hudson451513381622784795.sh
...
tools/hudson.plugins.mercurial.MercurialInstallation/mercurial_linux_home_27/hudson6590878454899114293.sh
...
tools/hudson.plugins.mercurial.MercurialInstallation/mercurial_linux_home_27/hudson864604609613003342.sh

[2]

Name: mercurial_linux_home_27
Executable: INSTALLATION/hg
Use Repository Caches: No
Use Repository Sharing: No
Debug: No

Label: install_hg
Command:
#sudo yum install -y python-devel docutils

wget http://mercurial.selenic.com/release/mercurial-2.7.tar.gz
tar xf mercurial-2.7.tar.gz
cd mercurial-2.7

make local

#export PYTHONPATH=${HOME}/lib/python
#export PATH=${HOME}/bin:$PATH

#echo -e "[extentions]\nlargefiles = " >> ~/.hgrc

Tool Home: mercurial-2.7