System diagnostic work area (SDWA) record

When a software error occurs, the system gathers diagnostic information for the error and places it into a system diagnostic work area (SDWA) control block. A recovery routine can request that the system create a software-type record from the information in the SDWA and record it to the logrec data set. This software record contains the following information (Table 1):

Standard record header information.
SDWA information such as registers, PSW, locks held at the time of error, completion code, data describing reasons and conditions for entering the recovery exit routine, the CSECT in which the error occurred, module name, and FRR ID. See z/OS® MVS™ Data Areas in http://www.ibm.com/systems/z/os/zos/bkserv/ for the detailed format of the SDWA.
Variable information that assists in isolating the specific error. A description of the specific variable information is in the program listing.
Error identifier to identify any associated machine check record or SVC dump.

Table 1. Format of the SDWA record
Offset		Size (bytes) alignment (bits)	Field name	Description
Dec	Hex	Size (bytes) alignment (bits)	Field name	Description
0	(0)	1	HDRTYP	Class/Source:
		.1.. ....		Software-detected software error; type=X'40'.
		.1.. ..1.		Hardware-detected software error; type=X'42'.
		.1.. .1..		Operator-detected error; type=X'44'.
		.1.. 1...		Hardware-detected hardware error; type=X'48'.
1	(1)	1	HDROPRN	System/Release level:
		100. ....		OS/VS2.
		bits 3-7
		0-1F		Release level 0-31.
2	(2)	1	HDRIS	Record-independent switches:
		x... ....		Reserved.
		.1.. ....		Time-of-day (TOD) clock instruction issued. Used in conjunction with date and time values at displacement 8.
		..1. ....		Record truncated. (When EREP detects this bit being on, it does not
				edit record but prints it out in hexadecimal.)
		...1 ....		Record created by MVS/SP Version 2 or 3.
		.... 1...		TIME macro used.
		.... .xxx		Reserved.
3	(3)	3	HDRDS	Record-dependent switches:
		Byte 0
		x... ....		Reserved.
		.1.. ....		Record incomplete. (Record truncated because of lack of buffer
				space.)
		..1. ....		Record contains an ERRORID.
		...x xxxx		Reserved.
		Byte 1		Reserved.
		Byte 2		Reserved.
6	(6)	1	HDRCNT	Not used for SDWA record.
7	(7)	1		Reserved.
8	(8)	8	HDRTM	Time-of-day clock.
16	(10)	1	HDRCPID	Machine version code.
17	(11)	3		Central processor serial number.
20	(14)	2		Central processor machine model number.
22	(16)	2		Reserved.

				END OF STANDARD HEADER

24	(18)	8	JOBID	Alphameric name assigned to job (as identified, for example, by a job name on a JCL JOB statement) being processed or requesting service at time of failure.
32	(20)	400	SDWA	The SDWA is described by the IHASDWA mapping macro. See z/OS MVS Data Areas in http://www.ibm.com/systems/z/os/zos/bkserv/ for the detailed SDWA data area.
432	(1B0)	264	SDWARA	Variable recording area.
435	(1B3)	1	SDWAURAL	Length of the variable recording area (SDWAVRA) containing recovery exit data.
436	(1B4)	variable	SDWAVRA	Contains FRR-dependent data such as damage assessment, recovery action information, and specific diagnostic information to assist in isolating or identifying problem. See the appropriate program listing for a description of specific data supplied by a recovery exit routine.
var.		456	SDWARC1	First recordable extension of the SDWA. Contains additional serviceability data. See z/OS MVS Data Areas in http://www.ibm.com/systems/z/os/zos/bkserv/ for the SDWA.
var.		16	SDWARC2	Second recordable extension of the SDWA. Contains additional data concerning I/O machine checks. See z/OS MVS Data Areas in http://www.ibm.com/systems/z/os/zos/bkserv/ for the SDWA.
var.		32	SDWARC3	Third recordable extension of the SDWA. Contains additional data concerning locks to be freed by RTM. See z/OS MVS Data Areas in http://www.ibm.com/systems/z/os/zos/bkserv/ for the SDWA.
var.		360	SDWARC4	Fourth recordable extension of the SDWA. Contains z/Architecture® information. See z/OS MVS Data Areas in http://www.ibm.com/systems/z/os/zos/bkserv/ for the SDWA.
var.		144	SDWARC5	Fifth recordable extension of the SDWA. See z/OS MVS Data Areas in http://www.ibm.com/systems/z/os/zos/bkserv/ for the SDWA.
var.		10	ERRORID	Error identifier - not part of the SDWA, but located directly after the SDWA in the logrec data set record. ERRORID consists of: 2-byte sequence number 2-byte CPU identifier 2-byte ASID 4-byte time stamp