3100503 - Bad TDS error 1622 caused infinite loop, out of memory error 701 and high CPU

• ASE became unavailable due to procedure cache usage at 100%.
  
  • Some processes raised error 701 due to no free memory in procedure cache memory pool. Message of error 701:
    
    "There is not enough procedure cache to run this procedure, trigger, or SQL batch. Retry later, or ask your SA to reconfigure ASE with more procedure cache."

• Some processes which were taking high CPU time and memory, 'dbcc pss(0, high_cpu_spid)' or sybmon command 'pss high_cpu_spid' show:
  • plasterror=1622                 --- last error = 1622, the bad TDS error message is 'Type xxx not implemented.'
  • pcpucur: high_value           --- cpu time for current statement was high
  • pmemusage: high_value     --- # of memory pages from procedure cache memory pool was high
• The high_cpu_spid was running in infinite loop with the following stack:
  
  ssl_nrpacket
  ksmask_rpacket
  kstcpnetctlrPostRead
  ksmaskrpost
  usrfill
  flushtoeom
  tdsrecv_errorhdl
  conn_hdlr

Adaptive Server Enterprise (ASE) 16.0

CR 825378, 825378, CR 825414, 825414, error 1622, infinite loop, tdsrecv_errorhdl , KBA , BC-SYB-ASE , Sybase ASE Database Platform (non Business Suite) , Known Error