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Large VP vs VP/HP ConfigurationLarge VP vs VP/HP Configuration20,000 Buffers5,000 Buffers15,000 BuffersMVS PagingPage Movement...MVPG or ADMFCSESCSESVirtual PoolVirtual PoolHiperPoolDBM1 SRBDBM1 SRB or Appl. TCB
Notes:
The HiperPool facility of V3 provides the ability to utilize ESO Hiperspaces as an extension of the Buffer Pools. When this facility is used, it provides almost (but not quite) identical performance to base pools adequately backed by central storage. The primary advantage to this approach, is the ability to keep large amounts of data in memory without driving up the MVS paging rate. Block migrations of data to/from the HiperPool are handled by a new facility ‘ADMF’ (Asynchronous Data Mover Facility) that runs under the IOP engine rather than a central processor engine. This reduces the cost of data movement vs. MVS paging of a normal data page by approximately 8%. Another reason for this approach is the MVS limit of 2 Gigabytes for an Address Space - such as the DB2 Database Manager. While there is a maximum limit of 1.6 Gigabytes of Buffer Pool space that can be defined, using all of this will certainly cause this address space to hit the 2 Gig limit when the EDM Pool is added, and later the RID and Sort Work pools are added in dynamically.
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