Solution : https://service.sap.com/sap/support/notes/524647 (SAP Service marketplace login required)
Key words : 
sgroup    type rfcgrmax_proc  type crmt_mkttggrp_max_procactive    type crmt_mkttggrp_para_activecom_medium type crm_mktpl_channeltechnical settings, processeslong            27    maximum parallel processesheading          27    maximum parallel processesshort text       crm marketing, crmc_mktpl_chan mandt crmc_mkt_parexec mandtcrmc_mktpl_chan channel crmc_mkt_parexec com_mediumthen activate, short            10    activemedium          15    activelong            20    activeheading          5    activshort text       crm marketing, application log ended002 content job guid003 active implementation, guid          type    crmt_object_guidobject_type  type    crmt_mkttg_seg_typeprobclass    type    balprobcl, order generation014 end order generation015 business partners, measurement results e-mail creation                      initial status, changing database entries module crm_mkttg_insert_pack_nbrshort text, campaign execution withserver groupsa large advantage
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