dbs/mss/dbsl_profile is a SAP Parameter attribute which is used to control MSSQL: Enable dbsl profile trace information. This is available within R/3 SAP systems depending on the version and release level.
Below is the standard documentation available and a few details of the attributes values .
When this parameter is turned on, files dbsl_w* will be created in the work directory. These files contain a detailed trace of DBSL functions.
See SAP Parameter Documentation for full SAP documentation for this profile parameter.