LOGCLOSET (JANUS DEFINE parameter)

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LOGCLOSET minutes — frequency of log 'closes'

LOGCLOSET is a parameter on JANUS DEFINE, which defines and sets characteristics of a Janus port.

This parameter indicates how often the Janus Web Server log dataset is to be "closed", that is how often the DSCB is to be updated for the log dataset.

LOGCLOSET is followed by the number of minutes between TYPE=T closes (DSCB updates) performed for the web log dataset.

There are two main reasons to set LOGCLOSET:

  1. If TYPE=T closes are not done for the log dataset, the log data for the current run cannot be seen by most MVS utilities (and some CMS utilities) until the port is stopped.
  2. If the Online should come down with a hard crash (say from a power outage or job cancellation) all the web log data from that run will be lost. If LOGCLOSET is set and a hard crash occurs, only the data logged after the last TYPE=T close would be lost.

If LOGCLOSET is not set for a port, no TYPE=T closes will be performed for the port.

Setting LOGCLOSET too low will cause lots of small blocks to be written to the log dataset, and it can cause a lot of DSCB activity, which is not very desirable (though no TYPE=T close will be performed if there were no requests since the last TYPE=T close). Setting LOGCLOSET too high could allow the loss of a lot of web log data. A reasonable setting for LOGCLOSET might be 60, which would risk the loss of up to an hour of web log data in the odd case of a hard Online crash, but it would ensure that no more than one DSCB update will be performed per hour for the log dataset.

Valid only for WEBSERV ports.

See also