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Home -> Community -> Mailing Lists -> Oracle-L -> Big RAC Benchmark Performance Tips?
Folks
A 4-node RAC BIG benchmark with Oracle 10g / AIX 5.3L using a Hybrid Banking App. is underway.
Qs1 Does Cache fusion(Traffic between the nodes thru the interconnects) continue to be an expensive operation in Oracle 10g?
To minimize Cache fusion, Manually Transactions have been grouped such that transactions accessing different DB Server Nodes access different respective Table partitions (& NOT the same Table partition). Thus Different Object BLOCKS are accessed in different DB Server nodes.
NOTE - Partitioning of heavier underlying tables has been done such that different partitions lie in DIFFERENT Tablespaces (& hence datafiles).
Qs2 Is Low Latency Protocol - LLT protocol (of Veritas) equivalent or something similar available with GPFS?
Currently default (UDP) is being used.
NOTE - A Past benchmark done by us on SUN using VXFS (Veritas) with both Low Latency Protocol (LLT) & User Datagram Protocol (UDP, Default) showed LLT had a 98% Lower interconnect utilization versus UDP.
Qs3 Any additional init.ora parameters for performance apart from the following which have been set?
db_writer_processes=16
db_cache_advice=OFF
event='10196 trace name context forever, level 10' (to disable index skip scan)
_library_cache_advice = FALSE
_log_simultaneous_copies 256
_b_tree_bitmap_plans = FALSE (as NO Bitmap indexes exist)
_check_block_after_checksum TRUE
_system_trig_enabled FALSE (Benchmark Has NO need for Triggers)
_wait_for_sync TRUE
NOTE - Standard features i.e. AUM, Tempfiles & ASSM are being used.
Qs4 Other best practices to deploy?
Will provide Statspack, Other diagnostics info. as needed.
Thanks indeed
Configuration:-
APP & DB machines - P5 series
Application Hybrid - (OLTP + Batch nature of Trans).
Oracle 10.2
AIX 5.3 Filesystem GPFS
Storage Box DS8300
Hardware RAID 1+0
Underlying Hardware Stripe Unit Size 64 KB
Overlying Logical Volume Manager Stripe Unit Size 32 MB (S.A.M.E.)
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