OS390_Cache_Write_HitPct_Crit

OS390_Cache_Write_HitPct_Crit monitors the percent of successful I/O requests to write temporary data to the cache and issues a Critical alert if the percentage is greater than 0 and less than or equal to 50%.

The formula is:

IF VALUE DASD_MVS_Devices.Cache_Write_Hit_Percent GT 0 AND DASD_MVS_Devices.Cache_Write_Hit_Percent LE 50

If this situation is raised, determine whether any address spaces that have this device number allocated are in service classes that are missing their goals. If goals are being missed, dataset placement (I/O tuning) may be required.