When we installed z/VM 5.2.0, DB2/VM crashed under heavy load with a corrupted catalog. It would not come back up. All we could do was restore to the last good backup (taken just before we installed z/VM 5.2.0). IBM
gave us a CP patch to turn off HPMA (explanation later) and then we ran fine for a week. We put the missing MCL (J13484.112) on and ran with both for a week, then backed off the CP patch. DB2/VM crashed in the same way with the same results. So we put the CP patch back on and have run fine since then. My question is, is anyone else seeing this? The CE swears up and down that the MCL is installed and activated. (All 3 required MCLs are now installed.) His boss agrees. We are running z/VM 5.2.0 and DB2/VM 7.4.0, with dataspaces (VMDSS) turne d on. We are running in an LPAR (2 engines, 2GB central + 1 GB expanded) of a z990. HPMA: From: Products: Networking for IBM eServer zSeries 890 and 990 at <http://www-03.ibm.com/servers/eserver/zseries/networking/osaeann.html>: Enhanced performance assists for z/VM Linux guests The z990 and z890 servers introduced an important virtualization technology designed to improve the performance of z/VM guest operating systems (such as Linux on System z9) when Queued Direct Input/Output (QDIO) is used for HiperSockets™, FCP, and OSA. This virtualization technology is designed to allow QDIO interruptions to be passed directly to guests for HiperSockets, Fibre Channel Protocol (FCP), and OSA on the z9-109, z990, and z890 servers. A complementary virtualization technology is being introduced for z9-109, z990, and z890. _ QDIO Enhanced Buffer-State Management (QEBSM) - Two new hardware instructions designed to help eliminate the overhead of hypervisor interception _ Host Page-Management Assist (HPMA) - An interface to the z/VM Central Storage management function designed to allow the hardware to assign, lock, and unlock page frames without z/VM hypervisor assistance The new hardware assists can allow a cooperating guest operating system t o initiate QDIO operations directly to the applicable channel, without interception by z/VM, thereby helping to provide additional performance improvements. The performance assists are provided on the z9-109, z990, and z890, for: _ HiperSockets, CHPID type IQD _ All FICON features with CHPID type FCP _ All OSA features with CHPID type OSD Alan Ackerman alan (dot) ackerman (at) bank of america (dot) com
