>From TIMEUSED documentation in "z/OS V1R10.0 MVS Authorized Assembler Services >Reference SET-WTO": Requires key zero and supervisor state to force using >Extract CPU Time instruction service (ECT=YES), but normal LINKAGE=SYSTEM can >use ECT=COND to use it if it is available.
,LINKAGE=SYSTEM ,LINKAGE=BRANCH Specifies the type of linkage used in TIMEUSED processing. LINKAGE=BRANCH indicates branch entry. You may specify or default to LINKAGE=BRANCH if you are a key zero supervisor state program running under a TCB or SRB. LINKAGE=SYSTEM indicates the linkage is by nonbranch entry. ,ECT=SYSTEM ,ECT=COND ,ECT=YES Specifies which instruction service the system is to use. SYSTEM Specifies that the system determines which instruction service to use. For LINKAGE=BRANCH, the system will use the Extract CPU Time instruction service when that service is available. For LINKAGE=SYSTEM, it will not use the Extract CPU Time instruction service. COND Specifies that the system is conditionally to use the Extract CPU Time instruction service. If the service and instruction are available, the system will use that service. Otherwise, the system will use the regular TIMEUSED service. Output is in TOD format. Use only with LINKAGE=SYSTEM. Do not specify the CPU or VECTOR parameters. You must include the CVT, IHAECVT, and IHAPSA mapping macros. YES Specifies that the system is unconditionally to use the Extract CPU Time instruction service. You must verify that the service and instruction are available (running on z/OS V1R8 or later, with bit FLCECT in byte FLCFACL3 in macro IHAPSA). Output is in TOD format. Do not specify the CPU, VECTOR, or LINKAGE parameters. You must include the CVT, IHAECVT, and IHAPSA mapping macros. HTH Peter > -----Original Message----- > From: IBM Mainframe Discussion List [mailto:[email protected]] On > Behalf Of Kirk Wolf > Sent: Thursday, February 03, 2011 3:35 PM > To: [email protected] > Subject: Re: STCK vs TIMUSED > > John, > > On a related matter: I seem to remember that there is a way to use > TIMEUSED > so that it has *significantly* less overhead, which would be important for > a > "profiler" use case. I'm not sure, but I recall that it has something to > do with BRANCH= and ECT=. > > If anyone knows the details on this, I would appreciate any info. -- This message and any attachments are intended only for the use of the addressee and may contain information that is privileged and confidential. If the reader of the message is not the intended recipient or an authorized representative of the intended recipient, you are hereby notified that any dissemination of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by e-mail and delete the message and any attachments from your system. ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [email protected] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
