IBM Support

Dealing with clock change (Daylight savings)

Technote (troubleshooting)


This is the workaround to deal with Daylight savings to ensure that the rest of the day's data can be loaded


LIFs data at the time clock change occurs will fail to be loaded and go to bad directory

Resolving the problem

For deployments in a time zone where the clocks change backwards, please follow the procedure below.

Note that if the clocks are changing forwards, and the workaround has been previously applied, it should be undone. Otherwise there is nothing to do in this situation.

Ensure that the following workaround is in place in the loadmap configuration in order to minimize potential loss of data/loading issues:

Note that these changes must be done the weekend of the clock change and BEFORE the clocks change.

Expression starttime column:

if (utime("02Jan00" & end,"%d%b%y%R")<= utime("02Jan00" & start,"%d%b%y%R")) &&

(end != "00:00"))

then utime(day & start,"%d%b%y%R") – 3600

else utime(day & start,"%d%b%y%R")

Expression endtime column:

if (end = "00:00")

then utime(day & start,"%d%b%y%R") + utime("02Jan00" & end,"%d%b%y%R") –

utime("01Jan00" & start, "%d%b%y%R")

else utime(day & end, "%d%b%y%R")

Note that the above changes will need to be reverted for the subsequent spring clock change. Note also that this does not completely solve the problem in that one hour's worth of data will be overwritten and there will be a one hour gap in the data. The workaround will ensure that the rest of the day's data can be loaded.

Document information

More support for: Metrica Performance Manager
Tech Packs

Software version: Version Independent

Operating system(s): Solaris

Reference #: 1382928

Modified date: 2009-11-13