I have one idea. it needs 2 build jobs use "Jenkins Parameterized Trigger plugin<https://wiki.jenkins-ci.org/display/JENKINS/Parameterized+Trigger+Plugin>" with "NodeLabel Parameter Plugin<https://wiki.jenkins-ci.org/display/JENKINS/NodeLabel+Parameter+Plugin> ".
1.Make "Job A". "Job A" poll SVN and pull triger "Job B" with "Trigger parameterized build on other projects" with "Node Label parameter" after job. 2.You need to add 8 trigers( it's count of slaves) for "Job B" with "Node Label parameter"(it's slave's host name.). 3."Job B" is test worker on slave. Not poll SVN. 4.if you want to change test parameter, to make parameter (ex."TEST_SCRIPT_PART") and use this parameter (ex."${TEST_SCRIPT_PART}") in "Job B" and to change or add parameter (ex."TEST_SCRIPT_PART") for slave in "Job A".