2791392 - Startup: work processes in status WP_NEW reason "Semaphore 50"

• On SM51 transaction, application has status “Starting” for long time. Eventually, it changes into “Active”.
  This can be seen on Dispatcher trace file (dev_disp): Application Server starts at one time stamp but its status changes from STARTING to ACTIVE -for example- one hour later.
   
• During that period, work processes are stuck with “New” status. Eventually, they may start correctly and change into “Wait” status.
   
• System is hanging, finding the error “Dispatcher running but Dialog Queue Standstill”. 

• Check the Application Server status with command:
   >> sapcontrol -nr $$ -function GetProcessList

   name, description, dispstatus, textstatus, starttime, elapsedtime, pid
   disp+work.EXE, Dispatcher, YELLOW, Running but bad dialog queue time: 1234.56 sec, <timestamp>, PID
   igswd.EXE, IGS Watchdog, GREEN, Running, <timestamp>, PID
   gwrd, Gateway, GREEN, Running, <timestamp>, PID
   icman, ICM, GREEN, Running, <timestamp>, PID

• Work process table can be extracted using command:
  >> sapcontrol -nr $$ -function ABAPGetWPTable

  No, Typ, Pid, Status, Reason, Start, Err, Sem, Cpu, Time, Program, Client, User, Action, Table
  0, DIA, <PID>, New, , yes, , 50, 0:00:02, 1385, , , SAPSYS, ,
  1, DIA, <PID>, New, , yes, , 50, 0:00:02, 1384, , , SAPSYS, ,
  2, DIA, <PID>, New, , yes, , -50, 0:00:02, 1381, , , SAPSYS, ,
  3, DIA, <PID>, New, , yes, , 50, 0:00:02, 1379, , , SAPSYS, ,
  4, DIA, <PID>, New, , yes, , 50, 0:00:02, 1374, , , SAPSYS, ,
  5, DIA, <PID>, New, , yes, , 50, 0:00:02, 1377, , , SAPSYS, ,
  6, DIA, <PID>, New, , yes, , 50, 0:00:02, 1381, , , SAPSYS, ,
  7, DIA, <PID>, New, , yes, , 50, 0:00:02, 1380, , , SAPSYS, ,
  [...]

In this particular example, work process 2 holding semaphore 50 (it stands for SEM_THRUN_ADM taskhandler runtime).

semaphore 50, pending updates, ThVBMarkOldRq, old update request(s) modified, Dispatcher running but Dialog Queue Standstill, transaction SM13, rdisp/vbstart, rdisp/vbdelete, 

, KBA , BC-CST-UP , Update , BC-CST-DP , Dispatcher, Task Handler , How To