CA-IDMS 16.0 Performance and Non-Stop Enhancements AUI meeting in France 27. November 2006 Manfred Höfer, CA Prinicipal Support Engineer
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 2 Release File Cache in Memory - Parallel Access Volume Exploitation - Dynamic System Trace Control - Varying Program Attributes - Short-on-Storage Notification - Journal and Recovery High Performance Storage Protect
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies bit Exploitation - Terminology - The line: 16 MB limit - The bar: 2 GB limit - Z-storage: Virtual storage above the bar 2 GB – 16 EB (Exabyte) - XA-storage. Virtual storage below the bar and above the line 16 MB – 2 GB
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies bit Exploitation - File caching in 64-bit storage IDMS - CV or Local 64-bit 31-bit Buffer Cache On a read: - look in cache - if found, move to buffer - if not found, read from file, copy to cache On a write: - copy to cache - write to file
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 5 Dataspace/Memory Cache The MEMORY CACHE clause replaces the use of the DATASPACE clause. - DATASPACE clause is still accepted for upward compatibility, but is no longer generated on displays. - The choice of whether to cache a file in memory or in a dataspace is determined at runtime based on the operating system: - In a z/OS 1.2 or later environment, files are cached in Z-storage. - In earlier releases of the operating system files are cached in dataspaces.
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 6 Memory Cache - Insufficient storage for memory cache: If MEMORY CACHE YES is specified and not enough Z-storage is available to cache a file in memory, processing continues depending on the DMCL-wide MEMORY CACHE clause LOCATION ANYWHERE dataspace storage is acquired LOCATION 64 BIT ONLY memory caching fails - Dynamically changing memory cache specification: The MEMORY CACHE specification for a file can be changed dynamically with the DCMT VARY FILE command.
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 7 PAV Exploitation Job 1 Job 2 Advantage CA-IDMS PAV Exploitation Concurrent I/Os per file Single I/O per track File 1 File 2
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 8 Dynamic System Trace Control - New DCMT commands DCMT Display SYSTRace DCMT Vary SYSTRace ON ENTries=nnnnn DCMT Vary SYSTRace OFF DCMT Display DBTRace DCMT Vary DBTRace ON ENTries=nnnnn DCMT Vary DBTRace OFF
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 9 Varying Program Attributes Enhanced VARY PROGRAM support - DCMT Vary PROgram xxxx DEFine LANguage ADSo|COBol… TYPe MAP|DIAlog|PROgram… MPMode ANY|SYStem... -RESIDENT cannot be changed -Disable program to change language or type
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 10 Short-On-Storage Notification - New message written to console if SOS DC Pool &01: SOS condition &02 Condition 0 : remaining storage is less than cushion (SOS) 1 : not enough contiguous storage available, request failed - Duplicate messages suppressed (No more than 1 per minute)
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 11 Journaling and Recovery - Faster recovery for long-running transactions - New SYSGEN and DCMT options force an ENDJ instead of a COMT when a COMMIT is issued - Less data has to be examined to locate the start of recovery unit - Reduced journal writes - JOURNAL TRANSACTION LEVEL extended to journal writes caused because updated pages are forced from the buffer
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 12 Journal Buffer Size (cont.) DCMT DISPLAY BUFFER - Journal Buffer - Size # In-Use Waits DB Ckpt JNL_BUFFER # of Recoveries I/O's in Buffer # of buffer waits If > 0, increase buffer size # recovery I/Os If large, increase buffer size
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 13 Journal Transaction Level - Enables deferring journal write until block is full - Fewer journal blocks written - Fewer journal I/Os - Better journal file utilization - While # of update transactions exceeds journal transaction level - CV defers write of journal block until it fills
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 14 Journal Transaction Level (cont.) - Journal transaction level should be - 0 (no deferral occurs) - Greater than 3 - If too large...no benefit - Monitor ARCHIVE JOURNAL report
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 15 Journal Full Cushion - Prevents system from hanging due to full journals - If available space less than cushion - Only checkpoint records can be written to journal - Other writers display message and wait - Allows administrator to cancel offending task - Then issue DCMT VARY JOURNAL - Implemented as a 15.0 APAR
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 16 Release File Cache in Memory - Parallel Access Volume Exploitation - Dynamic System Trace Control - Varying Program Attributes - Short-on-Storage Notification - Journal and Recovery High Performance Storage Protect
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 17 High Performance Storage Protect - With the introduction of the z-architecture machines, the cost of IDMS storage protection increased dramatically. - r16 SP2, introduces an alternate way to do storage protection that has very little (if any) performance impact. - The High Performance Storage Protect feature makes no attempt to protect the non-reentrant user programs or users’ storage from each other.
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 18 High Performance Storage Protect (cont.) - This feature makes use of the unique behavior of storage protect key 9 – any program can write in key 9 storage. Programs running in key 9 can only write in key 9 storage. - At startup, IDMS swaps the non-reentrant program pool and any storage pool supporting user storage to key 9. - When control is given to a user program, the PSW key is swapped to key 9 and swapped back upon returning.
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 19 High Performance Storage Protect (cont.) - It is expected that this feature will be used on production IDMS systems. - The traditional IDMS storage protect feature is still available and will typically still be used on test systems. - You can not use both the traditional and the high performance storage protect features at the same time, the new high performance storage protect feature takes precedence.
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 20 High Performance Storage Protect (cont.) - To enable, the DBA must employ key 9 and segregate all user-oriented storage from IDMS system storage. - To use the traditional storage protect feature, the system must be generated to use a key other than key 9.
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 21 High Performance Storage Protect (cont.) - Storage Pool Definitions - Range 128 to Range 1 to Storage types: User, User Kept, Shared, and Shared Kept can be together but must be defined to secondary storage pools segregated from Database or Terminal type storage. - SYSGEN storage protect key is 9 - Msg DC at startup if HPSPO is not possible
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 22 High Performance Storage Protect (cont.) With apar QO83615 you can see with DCPROFIL and with DCMT D ALL STO if HPSPO is enabled: - DCPROFIL SYSTEM STORAGE PROTECTED: YES HPSPO ENABLED: YES - DCMT D ALL STORAGE POOLS POOL ADDRESS SIZE CUSHION INUSE HWM TIMES PFIX CONTAINS SOS TYPES K 8K 60K 60K 0 NO SY,TR,DB K 52K 44K 52K 0 NO SH,SK,US,UK E K 100K 148K 164K 0 NO TR,DB D K 100K 1324K 1336K 0 NO SH,SK,US,UK FA K 0K 296K 312K 0 NO SY High Performance Storage Protection Option Enabled
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 23 Comparing „old“ and „new“ storage protection: Protection is set for system and program: STANDARD SP: When switching from User to System Mode or from System to User Mode, IDMS must run the task's resource chains and issue SVCs to switch stg key for all of that task's pages in memory as well as switching the stg key in the PSW. HPSPO (alternate key is 9): Since the entire non-reentrant stg pool and all stg pools that contain the user stg types will already be set to the alt key 9, IDMS only has to switch the PSW stg key.
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 24 Release 16.0 File Cache in Memory Parallel Access Volume Exploitation Dynamic System Trace Control Varying Program Attributes Short-on-Storage Notification Journal and Recovery 16.2 High Performance Storage Protect
Copyright ©2006 CA. All rights reserved. All trademarks, trade names, services marks and logos referenced herein belong to their respective companies. 25 QUESTIONS ?