informix 9.3 to 9.4 issue

Hello, I'm having some serious issues with a production instance of Informix and I can't figure out why. I'd been running 9.30.UC7 for over a year solid, no complaints. Monday night, I installed 9.40.UC8 and its been awful. What am I missing? I've been tweaking ONCONFIG and I'm still not there. Today, the CPU is through the roof and Informix doesn't appear to using all the memory that I'm throwing at it. Hardware is a Dell PE 1950 running Linux RHE 4.0 mirrored drives & 4GB of RAM here is a partial ONCONFIG: ROOTNAME rootdbs # Root dbspace nameROOTPATH /informix/data/rootdbs # Path for device containing root dbspace ROOTOFFSET 0 # Offset of root dbspace into device (Kbytes) ROOTSIZE 32000 # Size of root dbspace (Kbytes) # Physical Log Configuration PHYSDBS physdbs # Location (dbspace) of physical log PHYSFILE 32000 # Physical log file size (Kbytes) # Logical Log Configuration LOGFILES 147 # Number of logical log files LOGSIZE 2000 # Logical log size (Kbytes)LOG_BACKUP_MODE CONT # Logical log backup mode (MANUAL, CONT) # System Configuration SERVERNUM 0 # Unique id corresponding to a OnLine instance DBSERVERNAME infx010_ot # Name of default database server DBSERVERALIASES infx010_os # List of alternate dbservernames NETTYPE # Configure poll thread(s) for nettype DEADLOCK_TIMEOUT 60 # Max time to wait of lock in distributed env. RESIDENT 0 # Forced residency flag (Yes = 1, No = 0) MULTIPROCESSOR 1 # 0 for single-processor, 1 for multi-processor NUMCPUVPS 4 # Number of user (cpu) vps SINGLE_CPU_VP 0 # If non-zero, limit number of cpu vpsto one NOAGE 0 # Process aging AFF_SPROC 0 # Affinity start processor AFF_NPROCS 0 # Affinity number of processors # Shared Memory Parameters LOCKS 600000 # Maximum number of locks BUFFERS 400000 # Maximum number of shared buffers NUMAIOVPS 2 # Number of IO vps PHYSBUFF 128 # Physical log buffer size (Kbytes) LOGBUFF 128 # Logical log buffer size (Kbytes) CLEANERS 8 # Number of buffer cleaner processes SHMBASE 0x44000000L # Shared memory base address SHMVIRTSIZE 1024000 # initial virtual shared memory segmentsize SHMADD 256000 # Size of new shared memory segments (Kbytes) EXTSHMADD 8192 # Size of new extension shared memory segments (Kbytes) SHMTOTAL 0 # Total shared memory (Kbytes). 0=>unlimited CKPTINTVL 180 # Check point interval (in sec) LRUS 32 # Number of LRU queues LRU_MAX_DIRTY 60 # LRU percent dirty begin cleaning limit LRU_MIN_DIRTY 50 # LRU percent dirty end cleaning limit TXTIMEOUT 300 # Transaction timeout (in sec) STACKSIZE 32 # Stack size (Kbytes) # DBSPACETEMP: DBSPACETEMP tmpdbs # Default temp dbspaces