2469617 - User application hangs after sending a new command after a cancel

• User application hangs
• From the output of sysprocesses, the status of this spid is 'recv sleep':

select * from master..sysprocesses where spid = 39
go

spid kpid enginenum status suid hostname program_name hostprocess cmd cpu physical_io memusage blocked dbid uid gid tran_name time_blocked network_pktsz fid execlass priority affinity id stmtnum      linenum origsuid block_xloid clientname clienthostname clientapplname sys_id ses_id loggedindatetime ipaddr nodeid
------ ----------- ----------- ------------ ----------- -----------------------------------------------------------------------------------------------------------------------------
39 900006021 0 recv sleep 3 cdctst55 PowerMart 24969368 AWAITING COMMAND 86 0 2 0 5 1 0 $user_transaction NULL 2048 0 EC2 MEDIUM syb_default_pool 0 1 1 NULL 0 0 0 Jun 26 2016 12:27PM 160.80.39.204 NULL

• From Ribo output and dbcc sqltext(spid), ASE received the command that was sent from application, but have not sent out the results yet
• The cancel was handled and an attention ack was sent to the client, but the subsequent command did not get executed. ASE seems to be waiting for the client to send next command, while the client is waiting for ASE to execute the command it sent.

• Usually the issue can not be reproduced at will. It happens when the client sent a cancel followed by a new command.

• Stack trace may happen at function 'gotattn' as follows:
  --------------------------------------------------------------------
  gotattn
  ksnetctlrPostRead@AF49_15
  ksrequest_rpost
  aix_rpost.fdpr.chunk
  usrfill.fdpr.chunk
  recvhost.fdpr.chunk
  
  

• SAP Adaptive Server Enterprise (ASE) 15.7 SP101 and above
• SAP Adaptive Server Enterprise (ASE) 16.0

application hangs, recv sleep, CR#800370, CR800370, 800370, client, send command , KBA , BC-SYB-ASE , Sybase ASE Database Platform (non Business Suite) , Problem