This message is the first in a group of messages that displays tuning statistics for a SNA controller. A complete description of the message group follows.

IST440I    TIME = time         DATE = date         ID = id
IST441I  DLRMAX = dlrmax       CHWR = chwr       CHRD = chrd
IST442I    ATTN = attn        RDATN = rdatn      IPDU = ipdu
IST443I    OPDU = opdu        RDBUF = rdbuf     SLODN = slodn
IST1568I   INLP = inlp         ONLP = onlp      BFNLP = bfnlp
IST314I  END

IST440I

• time indicates the time (in hours, minutes, seconds, and hundredths of seconds) at which the record is recorded. For example, 07431380 means that the record was recorded at the 7th hour, 43rd minute, 13th second, and 80 one-hundredths of a second of the day.
• date is the date on which the tuning statistics report is recorded. The date is in the form yyddd, where yy is the last two digits of the numeric year and ddd is the numeric day of the year. For example, 00190 means the record is recorded on the 190th day of 2000.
• id is the name of the user-defined channel-attached SNA cluster controller or the name of the channel link that attaches the communication controller for which the statistics are gathered. For a VTAM-generated channel-link name, this field contains the channel unit address followed by "-L."

IST441I

• dlrmax is a decimal value that indicates the maximum number of dump-load-restart requests that were awaiting processing or were being processed at one time during the interval. This number refers to the entire domain, not to the SNA controller named in the report. The dump-load-restart subtask processes the following types of requests:
  • Dump, load, or restart of an NCP
  • Some VTAM® messages to the operator that require a reply
  • Session establishment and termination processing for a local major node
  • Any I/O to a configuration restart or NODELST file.
• This value can be used to determine the proper setting for the DLRTCB start option, which determines how many dump-load-restart requests can be processed concurrently. If DLRMAX consistently exceeds DLRTCB, it indicates that VTAM is serializing requests on the available TCBs and that performance might be affected.
• chwr is a decimal value that indicates the total number of write channel programs issued during the interval covered by this record.
• chrd is a decimal value that indicates the total number of read channel programs issued to read data. It does not include the read that informs the cluster controller to clear its buffers.

IST442I

• attn is a decimal value that indicates the total number of attention interrupts received from a controller, including the total number of READ ATTENTIONs (RDATN).
• rdatn is a decimal value that indicates the total number of times that the attention is included in the ending status on a read channel program (that is, the number of times that VTAM, after reading data, is requested with an attention to read more data).
• ipdu is a decimal value that indicates the total number of inbound (to VTAM) PDUs received from this controller.

IST443I

• opdu is a decimal value that indicates the total number of outbound (from VTAM) PDUs sent to this controller.
• rdbuf is a decimal value that indicates the total number of read buffers used.
• slodn is a decimal value that indicates the total number of times the controller has entered a slowdown condition; for NCP, this is the number of times the CWALL buffer threshold has been reached.
  Note: The SLODN field is not related to message IST211I. This message is issued at a threshold value greater than CWALL.

IST1568I

• inlp is a decimal value that indicates the total number of inbound (to VTAM) NLPs received from this controller.
• onlp is a decimal value that indicates the total number of outbound (from VTAM) NLPs sent to this controller.
• bfnlp is a decimal value that indicates the total number of bytes read from inbound NLPs.