IBM Mainframe Discussion List <[email protected]> wrote on 06/06/2007 11:47:39 AM:
> When I change the size of the System Trace Table (i.e. TRACE ST,512K), > where is the storage taken from? The storage for trace buffers is mapped in virtual in 31-bit storage in the TRACE address space. The real storage is 31-bit preferred (nonreconfigurable) storage. The architecture allows trace buffers to be addressed by 62 or 63 bit real addresses (I forget which without looking - the high order one or two bits of CR 12 is used for trace control, not addressing), but z/OS does not yet exploit this capability. Trace snapshots are in 31-bit virtual in the TRACE address space, and are pageable except during the actual copying process. While fixed for copying, they can be backed in any (including 64-bit) preferred storage. z/OS 1.9 allows larger values than 999K to be specified on the TRACE ST command, but the 31-bit addressing constraints for buffers and snapshots must be considered when considering the largest practical system trace size. Jim Mulder z/OS System Test IBM Corp. Poughkeepsie, NY ---------------------------------------------------------------------- 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
