Mainframe, MVS and zOS Discussion

Hi,

I have been reading about SMF records for knowledge and stuck on a phrase which seems to be used at many places in the docment and the phrase is, "end of interval". What exactly "end of interval" means, can someone please guide me on this? For example, it's written like, SMF 30 and subtype 2 & SMF 30 and subtype 3 are written at end of interval ...

In the SMFPRMxx member of SYS1.PARMLIB, the system programmer specifies the interval time (usually one of 15 minutes, 30 minutes, or 60 minutes -- the default is 30 although any value evenly divisible into 60 works) as well as the sync time (default is 00) which indicates when the interval ends (00 to 59). If an address space is executing when the interval end occurs, an SMF type 30 subtype 2 or 3 record will be generated.

... and the value of this is to be able to plot usage by time of day - e.g. CPU time in SMF 30(2,3) Interval records. (Likewise RMF.)