2936708 - Thread usage increases through the introduction of AIO feature post upgrading to IQ 16.1 SP04 - SAP IQ

• SAP IQ 16.1 SP04 introduces a new feature for Asynchronous I/O (AIO) that changes the internal threading model of IQ.
  
  
• Post upgrading to SAP IQ 16.1 SP04 customers may notice that the thread usage in the IQ process increases.
  
  
• Some queries may fail with "not enough server threads available for this query" "SQL Anywhere Error -1010011"  messages seen in the iqmsg file. 
  
  
• Post upgrading to SAP IQ 16.1 SP04 customers may also notice  in the std err file  (or console log) that the figure  for the -iqmt setting has increased significantly without the customer having made any manual chages to the startup switch in their .cfg configuration file.  
  
  
• Customers may also start to notice messages like "Using AIO based prefetch manager” in the console log at startup.
    
• IQ Sysmon debug monitoring data shows a significant increase in thread usage.
  
  

SAP IQ 16.1 SP04 upwards on any platform

sybase, crash, abort, SP_04, IQ161, IQ 16-1, upgrade, iqmt, -iqmt, iqnumbercpus, - iqnumbercpus, threads, Max_Threads_Per_Connection, Max_Threads_Per_Team, sp_iqsysmon, insufficient threads, -1010011, "thread starvation",  "out of thread", "-1010011", async,  feature , 'I/O' , input, output, 'file-system', mpx , KBA , BC-SYB-IQ , Sybase IQ , Product Enhancement