12c: Warning Message About Heavy Swapping Observation and ORA-700 [kskvmstatact: excessive swapping observed]
(Doc ID 1919850.1)
Last updated on JULY 02, 2023
Applies to:Oracle Database Exadata Express Cloud Service - Version N/A and later
Oracle Database Cloud Service - Version N/A and later
Oracle Database - Enterprise Edition - Version 188.8.131.52 to 184.108.40.206 [Release 12.1 to 12.2]
Oracle Cloud Infrastructure - Database Service - Version N/A and later
Oracle SuperCluster M7 Hardware - Version All Versions to All Versions [Release All Releases]
Information in this document applies to any platform.
With 12cR1, if the sum of swap+in and swap+on is more that 2% of the real memory of the system, alert_<sid>.log reports frequent information about memory being swapped like below:
WARNING: Heavy swapping observed on system in last 5 mins.
pct of memory swapped in [2.70%] pct of memory swapped out [0.00%].
Please make sure there is no memory pressure and the SGA and PGA
are configured correctly. Look at DBRM trace file for more details.
Errors in file <ADR_BASE>/diag/<product_type>/<prod_id>/<instance_id>/trace/<SID>_dbrm_21092.trc (incident=16909):
ORA-00700: soft internal error, arguments: [kskvmstatact: excessive swapping observed], , , , , , , , , , , 
Incident details in: <ADR_BASE>/diag/<product_type>/<prod_id>/<instance_id>/incident/incdir_16909/<SID>_dbrm_21092_i16909.trc
The sum of the pct memory swapped in and swapped out always appears to be higher that 2%.
The DBRM trace file shows information similar to:
Heavy swapping observed in last 5 mins: [pct of total memory][bytes] total swpin [ 3.60%][599496K], total swpout [ 0.00%][0K] vm stats captured every 30 secs for last 5 mins: swpin: swpout: [ 0.07%][ 12416K] [ 0.00%][ 0K] [ 0.38%][ 63712K] [ 0.00%][ 0K] [ 0.05%][ 9432K] [ 0.00%][ 0K] [ 0.81%][ 135488K] [ 0.00%][ 0K] [ 0.35%][ 59032K] [ 0.00%][ 0K] [ 0.22%][ 37744K] [ 0.00%][ 0K] [ 0.35%][ 58544K] [ 0.00%][ 0K] [ 0.62%][ 104592K] [ 0.00%][ 0K] [ 0.56%][ 93368K] [ 0.00%][ 0K] [ 0.15%][ 25168K] [ 0.00%][ 0K] Heavy swapping observed in last 5 mins: [pct of total memory][bytes] In 12.2, you will have some additional information in the incident trace file which will help you determine if the is a problem. The information also contains recommendations on actions to avoid the error as seen below; ========================================== INSTANCE-WIDE SWAP ALERT SUMMARY ------------------------------------------ WARNING: Heavy swapping observed on the system. Heavy swapping can lead to timeouts, poor performance, and instance eviction. To reduce swapping, reduce the memory usage of this database instance and/or other applications running on this server. total physical memory: 64266 MB bytes swapped in/out in last 5 mins: 1965460 KB cpu utilization: 40% SGA_TARGET: 24576 MB PGA_AGGREGATE_LIMIT: 0 MB maximum PGA allocated since startup: 31282 MB total PGA currently allocated: 31172 MB PGA_AGGREGATE_TARGET: 5120 MB Beware that PGA usage (31282 MB) exceeds PGA_AGGREGATE_TARGET (5120 MB). Decrease PGA usage by lowering PGA_AGGREGATE_TARGET and PGA_AGGREGATE_LIMIT. Reduce the memory usage of this database instance by lowering SGA_TARGET, PGA_AGGREGATE_TARGET, and/or PGA_AGGREGATE_LIMIT.
and the call stack trace associated with this incident looks like:
... kskvmstatact kskdbrmtoutact ksbcti ksbabs ksbrdp opirip opidrv sou2o ...
Upgraded to 12.1.
To view full details, sign in with your My Oracle Support account.
Don't have a My Oracle Support account? Click to get started!
In this Document