-------------------------------------------------------------------------------- SPECjAppServer(R)2004 Result Copyright (C) 2004 Standard Performance Evaluation Corporation -------------------------------------------------------------------------------- WebSphere 6.0 Application Server on eServer xSeries 365 Cluster -------------------------------------------------------------------------------- 1,343.47 SPECjAppServer2004 JOPS@Standard -------------------------------------------------------------------------------- Submitter: IBM Corporation SPEC license # 11 Test date: Nov-2004 -------------------------------------------------------------------------------- SUT CONFIGURATION -------------------------------------------------------------------------------- J2EE Server Nodes: 5 DB Server Nodes: 2 J2EE Server CPUs: 20 cores, 20 chips DB Server CPUs: 8 cores, 8 chips J2EE Instances: 5 DB Instances: 3 Other SUT Components: (1) IBM eServer xSeries 335 running IBM Load Balancer V6.0 (1) IBM eServer xSeries 335 running WebSphere Deployment Manager V6.0 (1) 3COM 4924 Switch -------------------------------------------------------------------------------- BENCHMARK SETTINGS -------------------------------------------------------------------------------- Dealer Injection Rate: 805 Ramp Up Time: 1,200 sec # of Dealer Agents: 18 Ramp Down Time: 600 sec # of Manufacturing Agents: 10 Steady State Time: 3,600 sec DB Load Injection Rate: 900 Trigger Time: 600 sec -------------------------------------------------------------------------------- Detailed Results -------------------------------------------------------------------------------- Dealer Transaction Mix Count Tx. Mix Purchase 727,081 25.03% Manage 726,026 24.99% Browse 1,452,003 49.98% Total # Dealer Transactions 2,905,110 Total # Manufacturing Transactions 1,931,384 Response Times Average Maximum 90th% Reqd Purchase 0.75 6.80 1.60 2.00 Manage 0.61 12.88 1.20 2.00 Browse 0.90 8.50 1.70 2.00 Manufacturing 2.64 8.10 4.50 5.00 Reproducibility Run (SPECjAppServer2004 JOPS) 1,343.60 -------------------------------------------------------------------------------- SOFTWARE PRODUCTS -------------------------------------------------------------------------------- WebSphere 6.0 Application Server Network Deployment Vendor: IBM Corporation Availability Date: Dec-2004 Date Passed CTS: Nov-2004 CTS Version: 1.4 EJB Protocol: RMI/IIOP OS Name: Suse Linux Enterprise Server 9 -------------------------------------------------------------------------------- Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2) Vendor: IBM Corporation Availability Date: Dec-2004 OS Name: Suse Linux Enterprise Server 9 -------------------------------------------------------------------------------- IBM DB2 Universal JDBC Drivers (XA and non-XA) Vendor: IBM Corporation Availability Date: Dec-2004 OS Name: Suse Linux Enterprise Server 9 -------------------------------------------------------------------------------- IBM DB2 V8.2 Vendor: IBM Corporation Availability Date: Dec-2004 OS Name: Suse Linux Enterprise Server 9 -------------------------------------------------------------------------------- IBM Load balancer, Edge Component of WebSphere V6.0 Vendor: IBM Corporation Availability Date: Dec-2004 Description: Load balancer via MAC forwarding -------------------------------------------------------------------------------- WebSphere V6.0 Deployment Manager Vendor: IBM Corporation Availability Date: Dec-2004 Description: To setup and control WebSphere cell -------------------------------------------------------------------------------- SOFTWARE CONFIGURATIONS -------------------------------------------------------------------------------- J2EE Application Servers J2EE Product: WebSphere 6.0 Application Server Network Deployment JVM Product: Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2) JDBC Product: IBM DB2 Universal JDBC Drivers (XA and non-XA) Hardware: J2EE Application Server HW # of Instances: 5 Interfaces: Web Interface for the Dealer Domain Web Interface for the Supplier Domain EJB Interface for the Dealer Domain EJB Interface for the Manufacturing Domain EJB Interface for the Supplier Domain Notes / Tuning Information Minimum heap size = 2300 MB Maximum heap size = 2300 MB JVM parms: -Xlp verbose:gc com.ibm.CORBA.FragmentSize=3000 com.ibm.ws.pm.batch=true com.ibm.ws.pm.deferredcreate=true EJB Cache Size = 16553 HTTP Channel maximum persistent requests = -1 HTTP Channel readTimeout = 6000 HTTP Channel writeTimeout = 6000 HTTP Channel persistentTimeout = 3000 Minimum Web Container threads = 28 Maximum Web Container threads = 28 Minimum ORB threads = 34 Maximum ORB threads = 34 Minimum Default threads = 11 Maximum Default threads = 11 Trace and PMI disabled Auto file synchronization = disabled Refer to files appservers/resources.xml, appservers/startup.txt, and appservers/server.xml in the archive file. They contain: datasource configuration, JVM command line parameters, and other J2EE configuration information -------------------------------------------------------------------------------- Emulator SW Config JVM Product: Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2) Web Product: WebSphere 6.0 Application Server Network Deployment Hardware: Emulator # of Instances: 1 Notes / Tuning Information Initial heap size = 1024 MB Maximum heap size = 1024 MB JVM parm -Xss128k HTTP Channel readTimeout = 6000 HTTP Channel writeTimeout = 6000 HTTP Channel persistentTimeout = 3000 -------------------------------------------------------------------------------- Database SW Config DB Product: IBM DB2 V8.2 Hardware: Database Server #1 HW # of Instances: 2 Notes / Tuning Information Tuning performed by db2tune8 scripts in the archive/Schema/Database_1 directory. -------------------------------------------------------------------------------- Database SW Config DB Product: IBM DB2 V8.2 Hardware: Database Server #2 HW # of Instances: 1 Notes / Tuning Information Tuning performed by db2tune8 script in the archive/Schema/Database_2 directory. -------------------------------------------------------------------------------- Driver SW Config Primary JVM Product: Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2) Hardware: Load Drivers # of Instances: 1 Notes / Tuning Information JVM_OPTIONS=-Xss128k -Xms1152m -Xmx1152m -Dcom.ibm.CORBA.FragmentSize=3000 -------------------------------------------------------------------------------- Driver SW Config Satellites #1, #2, and #3 JVM Product: Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.2) Hardware: Load Drivers # of Instances: 3 Notes / Tuning Information JVM_OPTIONS=-Xss128k -Xms1152m -Xmx1152m -Dcom.ibm.CORBA.FragmentSize=3000 -------------------------------------------------------------------------------- IBM Load Balancer 6.0 Other Product: IBM Load balancer, Edge Component of WebSphere V6.0 Hardware: Load Balancer Hardware # of Instances: 1 Notes / Tuning Information Defaults used. -------------------------------------------------------------------------------- HARDWARE SYSTEMS -------------------------------------------------------------------------------- J2EE Application Server HW (SUT hardware) Hardware Vendor: IBM Corporation Model Name: IBM eServer xSeries 365 Processor: Intel Xeon MP MHz: 3000 # of CPUs: 4 cores, 4 chips, 1 core/chip (2 HW threads/chip) Memory (MB): 8192 L1 Cache: 12Kuops(I)+8KB(D) per chip L2 Cache: 512KB per chip Other Cache: 4MB L3 per chip OS Vendor: SuSE Inc. OS Name: SuSE Linux Enterprise Server 9 Disks: 2x36.4GB 15K RPM Ultra 320 SCSI (using x365 integrated mirroring) Network Interface: 1000BASE-TX Gigabit Integrated Ethernet Other Hardware: # of Systems: 5 H/W Available: Apr-2004 O/S Available: Sep-2004 Notes / Tuning Information These entries added to /etc/init.d/sysctl.conf net.core.netdev_max_backlog = 3000 net.core.somaxconn = 3000 net.ipv4.tcp_fin_timeout = 30 net.ipv4.conf.all.arp_ignore = 3 net.ipv4.conf.all.arp_announce = 2 vm.nr_hugepages = 1150 kernel.shmmax = 2511724800 kernel.shmall = 2511724800 These entries are added to /root/.ptofile ulimit -n 10000 echo 0x10000000 > /proc/self/mapped_base ip addr add 5.16.200.156/32 scope host dev lo -------------------------------------------------------------------------------- Database Server #1 HW (SUT hardware) Hardware Vendor: IBM Corporation Model Name: IBM eServer xSeries 365 Processor: Intel Xeon MHz: 3000 # of CPUs: 4 cores, 4 chips, 1 core/chip (2 HW threads/chip) Memory (MB): 8192 L1 Cache: 12Kuops(I)+8KB(D) per chip L2 Cache: 512KB per chip Other Cache: 4MB L3 cache per chip OS Vendor: Novell Inc. OS Name: SuSE Linux Enterprise Server 9 Disks: 2x36.4GB 15K RPM SCSI Network Interface: 1000BASE-TX Other Hardware: Four ServeRAID 6M controllers each connected to separate EXP400 Storage Units each with 14x36.4GB 15K Ultra320 SCSI disks. See diagrams: db_tables.JPG and db_logs.JPG in the archive. # of Systems: 1 H/W Available: Apr-2004 O/S Available: Sep-2004 Notes / Tuning Information This entry was added to /root/.profile ulimit -n 10000 These entries added to /etc/init.d/sysctl.conf vm.nr_hugepages = 2000 kernel.sem="250 32000 32 4096 -------------------------------------------------------------------------------- Database Server #2 HW (SUT hardware) Hardware Vendor: IBM Corporation Model Name: IBM eServer xSeries 365 Processor: Intel Xeon MHz: 3000 # of CPUs: 4 cores, 4 chips, 1 core/chip (2 HW threads/chip) Memory (MB): 8192 L1 Cache: 12Kuops(I)+8KB(D) per chip L2 Cache: 512KB per chip Other Cache: 4MB L3 cache per chip OS Vendor: Novell Inc. OS Name: SuSE Linux Enterprise Server 9 Disks: 2x36.4GB 15K RPM SCSI Network Interface: 1000BASE-TX Other Hardware: Two ServeRAID 6M controllers each connected to separate EXP400 Storage Units each with 14x36.4GB 15K Ultra320 SCSI disks. See diagrams: db_tables.JPG and db_logs.JPG in the archive. # of Systems: 1 H/W Available: Apr-2004 O/S Available: Sep-2004 Notes / Tuning Information This entry was added to /root/.profile ulimit -n 10000 These entries added to /etc/init.d/sysctl.conf vm.nr_hugepages = 2000 kernel.sem="250 32000 32 4096 -------------------------------------------------------------------------------- Load Balancer Hardware (SUT hardware) Hardware Vendor: IBM Corporation Model Name: IBM eServer xSeries 335 Processor: Intel Xeon DP MHz: 3200 # of CPUs: 2 cores, 2 chips, 1 core/chip (2 HW threads/chip) Memory (MB): 4096 L1 Cache: 12Kuops(I)+8KB(D) per chip L2 Cache: 512KB per chip Other Cache: 2MB L3 cache per chip OS Vendor: Novell Inc. OS Name: SuSE Linux Enterprise Server 9 Disks: 2x36.4GB 15K RPM Ultra 320 SCSI (using x335 integrated mirroring) Network Interface: 1000BASE-TX Gigabit Other Hardware: # of Systems: 1 H/W Available: Apr-2004 O/S Available: Sep-2004 Notes / Tuning Information These entries added to /etc/init.d/sysctl.conf net.core.netdev_max_backlog = 20000 net.core.somaxconn = 20000 nnet.ipv4.tcp_fin_timeout = 30 net.ipv4.tcp_syn_retries = 20 net.ipv4.tcp_synack_retries = 20 This entry was added to /root/.profile ulimit -n 10000 -------------------------------------------------------------------------------- WebSphere Deployment Manager (SUT hardware) Hardware Vendor: IBM Corporation Model Name: IBM eServer xSeries 335 Processor: Intel Xeon DP MHz: 3200 # of CPUs: 2 cores, 2 chips, 1 core/chip (2 HW threads/chip) Memory (MB): 4096 L1 Cache: 12Kuops(I)+8KB(D) per chip L2 Cache: 512KB per chip Other Cache: 2MB L3 cache per chip OS Vendor: Novell Inc. OS Name: SuSE Linux Enterprise Server 9 Disks: 2x36.4GB 15K RPM Ultra 320 SCSI (using x335 integrated mirroring) Network Interface: 1000BASE-TX Gigabit Other Hardware: # of Systems: 1 H/W Available: Apr-2004 O/S Available: Sep-2004 Notes / Tuning Information These entries added to /etc/init.d/sysctl.conf net.core.netdev_max_backlog = 6000 net.core.somaxconn = 6000 nnet.ipv4.tcp_fin_timeout = 30 net.ipv4.tcp_synack_retries = 20 This entry was added to /root/.profile ulimit -n 10000 -------------------------------------------------------------------------------- Emulator (non-SUT hardware) Hardware Vendor: IBM Corporation Model Name: IBM eServer xSeries 335 Processor: Intel Xeon DP MHz: 3200 # of CPUs: 2 cores, 2 chips, 1 core/chip (2 HW threads/chip) Memory (MB): 4096 L1 Cache: 12Kuops(I)+8KB(D) per chip L2 Cache: 512KB per chip Other Cache: 2MB L3 cache per chip OS Vendor: Novell Inc. OS Name: SuSE Linux Enterprise Server 9 Disks: 2x36.4GB 15K RPM Ultra 320 SCSI (using x335 integrated mirroring) Network Interface: 1000BASE-TX Gigabit Other Hardware: # of Systems: 1 H/W Available: Apr-2004 O/S Available: Sep-2004 Notes / Tuning Information These entries added to /etc/init.d/sysctl.conf net.core.netdev_max_backlog = 1000 net.core.somaxconn = 2000 nnet.ipv4.tcp_fin_timeout = 30 This entry was added to /root/.profile ulimit -n 10000 -------------------------------------------------------------------------------- Load Drivers (non-SUT hardware) Hardware Vendor: IBM Corporation Model Name: IBM eServer xSeries 335 Processor: Intel Xeon DP MHz: 3200 # of CPUs: 2 cores, 2 chips, 1 core/chip (2 HW threads/chip) Memory (MB): 4096 L1 Cache: 12Kuops(I)+8KB(D) per chip L2 Cache: 512KB per chip Other Cache: 2MB L3 cache per chip OS Vendor: Novell Inc. OS Name: SuSE Linux Enterprise Server 9 Disks: 2x36.4GB 15K RPM Ultra 320 SCSI (using x335 integrated mirroring) Network Interface: 1000BASE-TX Gigabit Other Hardware: # of Systems: 4 H/W Available: Apr-2004 O/S Available: Sep-2004 Notes / Tuning Information These entries added to /etc/init.d/sysctl.conf net.core.netdev_max_backlog = 1000 net.core.somaxconn = 2000 nnet.ipv4.tcp_fin_timeout = 30 -------------------------------------------------------------------------------- BENCHMARK MODIFICATIONS -------------------------------------------------------------------------------- Schema Modifications: No changes were made to the benchmark schema. -------------------------------------------------------------------------------- Load Program Modifications: No changes were made to the load program. BENCHMARK CONFIGURATION INFORMATION -------------------------------------------------------------------------------- Isolation Requirement Info: The following beans: PartEnt, ComponentEnt, AssemblyEnt, BomEnt and LargeOrderEnt in the Manufacturing Domain, ItemEnt in the Orders Domain, and SupplierCompEnt and SupplierEnt in the Supplier Domain were accessed using READ_COMMITTED (Access Intent's of wsOptimisticUpdate or wsOptimisticRead) which is Cursor Stability (CS) for DB2. The remaining beans were accessed using REPEATABLE_READ (Access Intent's of wsPessimisticUpdate, wsPessimisticRead or wsPessimisticWeakestLockAtLoad) (which translates to DB2 isolation level of Read Stability (RS). The ItemEnt bean was cached for 20 minute intervals using the WebSphere Lifetime in Cache Mechanism. Only the data inside the bean was cached. -------------------------------------------------------------------------------- Durability Requirement Info: To ensure database durability, RAID 50 (composed of two RAID 5E arrays) was used for the database logs maintained on the EXP400 Storage Expansion Units. Each application server has a pair of mirrored disks (using the x365 integrated mirroring). This provides durability for XA transaction logs. -------------------------------------------------------------------------------- Storage Requirement Info: Over the course of a 90 minute run at an injection rate of 805, the database storage for database system #1 increased 678 MB; database system #2 storage increased by 1028 MB. Given a linear scale, a 24 hour run at the same injection rate would increase storage for database system #1 by 10848 MB and database system #2 by 16448 MB. The EXP 400 Disk enclosures each contain fourteen 36.4GB drives. The ServeRAID 6M adapter utilized these drives as a RAID 50 array consisting of two RAID 5E arrays of 7 drives each. This yields a total disk storage of 419879 MB for each EXP400 storage unit. -------------------------------------------------------------------------------- Argument Passing Semantics: WebSphere Application Server V6.0 uses pass-by-value semantics by default. BILL OF MATERIALS -------------------------------------------------------------------------------- IBM x365 WebSphere 6.0 Cluster with DB2 v8.2 Database Server Supplier IBM x365 WebSphere V6 Hardware (for five systems) Unit Qty Description Part Number IBM 5 IBM xSeries 365 8862-6RX IBM 10 3.0GHz 4MB L3 Intel Xeon Processor MP included in 8862-6RX IBM 20 512MB PC2100 DDR SDRAM;24X CD-ROM includen in 8862-6RX IBM 5 REMOVE STANDARD MEMORY 09N8043 IBM 20 2GB PC2100 CL2.5 ECC DDR SDRAM RDIMM 33L5040 IBM 10 3.0GHz 4MB L3 Cache Upgrade With Xeon Processor MP 13N0710 IBM 5 Integrated Mirroring 01R1356 IBM 10 IBM 36.4 GB 15K RPM ULTRA320 SCSI HOT-SWAP HDD 32P0734 IBM 5 Warranty service upgrade; 3 yr onsite repair 24x7x4 96P2253 IBM x365 Database Hardware (for database #1 system) Unit Qty Description Part Number IBM 1 IBM xSeries 365 8862-6RX IBM 2 3.0GHz 4MB L3 Intel Xeon Processor MP included in 8862-6RX IBM 4 512MB PC2100 DDR SDRAM;24X CD-ROM includen in 8862-6RX IBM 1 REMOVE STANDARD MEMORY 09N8043 IBM 4 2GB PC2100 CL2.5 ECC DDR SDRAM RDIMM 33L5040 IBM 2 3.0GHz 4MB L3 Cache Upgrade With Xeon Processor MP 13N0710 IBM 1 Integrated Mirroring 01R1356 IBM 2 IBM 36.4 GB 15K RPM ULTRA320 SCSI HOT-SWAP HDD 32P0734 IBM 4 ServeRAID-6M Ultra320 SCSI Controller (256MB Cache) 02R0988 IBM 1 Warranty service upgrade; 3 yr onsite repair 24x7x4 96P2253 IBM x365 Database Hardware (for database #2 system) Unit Qty Description Part Number IBM 1 IBM xSeries 365 8862-6RX IBM 2 3.0GHz 4MB L3 Intel Xeon Processor MP included in 8862-6RX IBM 4 512MB PC2100 DDR SDRAM;24X CD-ROM includen in 8862-6RX IBM 1 REMOVE STANDARD MEMORY 09N8043 IBM 4 2GB PC2100 CL2.5 ECC DDR SDRAM RDIMM 33L5040 IBM 2 3.0GHz 4MB L3 Cache Upgrade With Xeon Processor MP 13N0710 IBM 1 Integrated Mirroring 01R1356 IBM 2 IBM 36.4 GB 15K RPM ULTRA320 SCSI HOT-SWAP HDD 32P0734 IBM 2 ServeRAID-6M Ultra320 SCSI Controller (256MB Cache) 02R0988 IBM 1 Warranty service upgrade; 3 yr onsite repair 24x7x4 96P2253 Storage Hardware (for database #1 system) Unit Qty Description Part Number IBM 4 EXP400 External SCSI Storage Enclosure 17331RU IBM 4 VHDCI SCSI 2m cable - one cable included in 17331RU IBM 4 IBM EXP400 - 3yr Warranty Service Uprade (24x7x4) 41L2768 IBM 56 IBM 36.4 GB 15K RPM ULTRA320 SCSI HOT-SWAP HDD 32P0734 Storage Hardware (for database #2 system) Unit Qty Description Part Number IBM 2 EXP400 External SCSI Storage Enclosure 17331RU IBM 2 VHDCI SCSI 2m cable - one cable included in 17331RU IBM 2 IBM EXP400 - 3yr Warranty Service Uprade (24x7x4) 41L2768 IBM 28 IBM 36.4 GB 15K RPM ULTRA320 SCSI HOT-SWAP HDD 32P0734 Two x335 systems for Deployment Manager and Load Balancer Unit Qty Description Part Number IBM 2 IBM xSeries 335 8676-J1X IBM 3200 MHZ 533 MHZ 2MB L3 CACHE INTEL XEON PROCESSOR included in 8676-J1X IBM 2 X 512MB PC2100 DDR SDRAM (CHIPKILL);24X CD-ROM included in 8676-J1X IBM 2 IBM XSERIES 335 - 3YR WARRANTY SERVICE UPGRADE (24X7X4) 21P2073 IBM 2 REMOVE STANDARD MEMORY 09N8043 IBM 2 xSERIES 3.2 GHz/533MHz-2MB L3 CACHE UPGRADE WITH XEON PROCESSOR 13N0662 IBM 8 IBM 1 GB PC2100 CL2.5 ECC DDR SDRAM DIMM 33L5039 IBM 2 Integrated Mirroring 01R1356 IBM 4 IBM 36.4 GB 15K RPM ULTRA320 SCSI HOT-SWAP HDD 32P0734 Miscellaneous Hardware Unit Qty Description Part Number IBM 1 NetBAY42 ER Enterprise Rack 930842S IBM 1 NetBay - 3yr Warranty Service Upgrade (24x7x4) 41L2762 3COM 1 3COM SUPERSTACK 3 SWITCH 4924 3C17701-US 3COM 3 3COM 1YR 24X7X4 EXPRESS SUPPORT - CAT10 3CS-EX74-10E IBM 1 E54 15 INCH BLACK CRT MONITOR (13.8INCH VIEWABLE) 633147N IBM 1 E54 - 3YR WARRANTY SERVICE UPGRADE (24X7X4) 30L9183 IBM 1 Preferred Pro Full Size PS/2 Keyboard - US English 31P7415 ibm 1 IBM USB Optical Wheel Mouse 06P4069 Passport Advantage Software Unit Qty Description Part Number IBM 8 DB2 UDB WORKGROUP SERVER UNLIMITED EDITION PROCESSOR LIC+SW MAINT 12 MO D51NDLL IBM 16 DB2 UDB WORKGROUP SERVER UNLIMITED EDITION PROCESSOR SW MAINT RNWL 1 ANNIV E00IHLL IBM 1 WAS NETWORK DEPLOYMENT V6.0.0 Multilingual MEDIA PK BA0DMML IBM 22 WAS Network Deployment Per Processor License & SW Maintenance 12 Months D5ALTLL IBM 44 WAS Network Deployment Per Processor SW Maintenance Annual Renewal E1ALVLL IBM 1 EDGE SERVER - LOAD BALANCING, CACHING,CENTRALIZED SECURITY included in D5ALTLL IBM 1 EDGE SERVER - SUPPORT included in E1ALVLL Operating System Software Unit Qty Description Part Number SuSE 1 SUSE LINUX ENTERPRISE SERVER 9 FOR X86 ... Software Media Kit 892-000328-001 SuSE 9 PREMIUM SUPPORT FOR SLES9 X86 FOR 3 YEARS SUSE QUOTE SuSE 9 MAINTENANCE PROGRAM FOR SLES9 X86 FOR 3 YEARS SUSE QUOTE -------------------------------------------------------------------------------- OTHER BENCHMARK INFORMATION -------------------------------------------------------------------------------- The switch ports and all network adapters are 1Gb/sec. Two types of load balancing were utilized: WebSphere's workload management performed load balancing for RMI/IIOP requests. IBM Load Balancer balanced HTTP connections across the WebSphere nodes. This submission used the xerces implementation (version - XML4J 4.3) provided with WebSphere Application Server V6.0 in the IBM 1.4.2 JDK. -------------------------------------------------------------------------------- General Notes -------------------------------------------------------------------------------- The only errors in the driver log files were those that are normally generated by this benchmark. The IBM DB2 Universal JDBC Drivers (XA and non-XA) is a type 4 driver. DB2 uses "Soft" checkpoint to ensure that no updates remain unflushed for longer than the allowed time. When DB2 UDB Server changes a database table with an update, insert, or delete operation, the change is initially made in memory, not on disk. When there is not enough space in the memory buffer to read in or write additional data pages, DB2 UDB Server will make space by flushing some modified pages to disk. Modified pages are also written to disk as part of the "Soft" checkpoint to ensure that no updates remain unflushed for longer than the allowed time. Before a change is made to the database, it is first recorded in the transaction log. This ensures that the database can be recovered completely in the event of a failure. Using the transaction log, transactions that started but did not complete prior to a failure can be undone, and transactions recorded as complete in the transaction log but not yet written to disk can be redone. DB2 UDB uses a write-ahead-logging protocol to guarantee recovery. This protocol uses "Soft" checkpoint to write least-recently-used database pages to disk independent of transaction commit. However, enough log information to redo/undo the change to a database pages is committed to disk before the database page itself is written. This protocol therefore renders checkpoint unnecessary for DB2 UDB. For a more detailed description of the general principles of the write-ahead-logging protocol, see the IBM research paper, ARIES: A Transaction Recovery Method Supporting Fine Granularity Locking and Partial Rollbacks Using Write-Ahead Logging," by C. Mohan, Database Technology Institute, IBM Almaden Research Center. (http:// portal.acm.org/citation.cfm ?id=128770&coll=portal&dl=ACM&CFID=10343790&CFTOKEN=42047146) XA 2-phase transactions were used to coordinate the interaction between the database instances, and between database server and JMS servers. -------------------------------------------------------------------------------- For questions about this result, please contact the submitter: IBM Corporation For other inquiries, please contact SPEC - Benchmark run on Sun Nov 21 00:27:01 EST 2004 by SPECjAppServer2004 v1.03 - Result submitted on Wed Nov 24 03:03:02 EST 2004 - Report generated by SPECjAppServer2004 Reporter v1.03 Copyright (C) 2004 Standard Performance Evaluation Corporation