Correct transaction management. cf. bug https://openrdf.atlassian.net/browse/SES-2295 and tomcat default management of PUT request with form data (application/x-www-form-urlencoded encoded)
<IfModule mpm_itk_module>
StartServers <%= @startservers %>
MinSpareServers <%= @minspareservers %>
MaxSpareServers <%= @maxspareservers %>
ServerLimit <%= @serverlimit %>
MaxClients <%= @maxclients %>
MaxRequestsPerChild <%= @maxrequestsperchild %>
</IfModule>