Thanks John, from node-1 CR Current Inst No Block Class Blocks Received % Immed % Busy % Congst Blocks Received % Immed % Busy % Congst 1 data block 5,865 99.13 0.68 0.19 116,160 92.72 0.00 7.28 1 Others 16 100.00 0.00 0.00 50 100.00 0.00 0.00 1 undo header 11 81.82 18.18 0.00 10 100.00 0.00 0.00 1 undo block 1 100.00 0.00 0.00 0 from node-2 CR Current Inst No Block Class Blocks Received % Immed % Busy % Congst Blocks Received % Immed % Busy % Congst 2 data block 236 97.88 2.12 0.00 740,773 99.78 0.00 0.22 2 Others 832 100.00 0.00 0.00 152 100.00 0.00 0.00 2 undo header 129 100.00 0.00 0.00 11 90.91 9.09 0.00 2 undo block 1 100.00 0.00 0.00 0 somehow I am not able to relate the 218.12% buffer cache and buffer-cache disk of -119.42 -Kart On Sat, Mar 13, 2010 at 5:26 PM, John Kanagaraj <john.kanagaraj@xxxxxxxxx>wrote: > Kart, > > Without know what *else* was running at that time, it is only possible to > guess. Having the complete AWR report (from both nodes, and assuming 10g) > may help. Specifically, look at the last few sections of a RAC AWR report > that lists type and statistics of GC traffic. > > John > > > On Sat, Mar 13, 2010 at 12:15 PM, K R <kp0773@xxxxxxxxx> wrote: > >> Hi, >> >> in one of our 2 node -RAC database in one node >> >> I observe >> >> Instance Efficiency Percentages (Target 100%) >> >> Buffer Nowait %: 92.30 Redo NoWait %: 100.00 Buffer Hit %: 218.12 In-memory >> Sort %: 100.00 Library Hit %: 99.07 Soft Parse %: 98.18 Execute to Parse >> %: 47.41 Latch Hit %: 99.74 Parse CPU to Parse Elapsd %: 1.77 % Non-Parse >> CPU: 88.86 >> >> Global Cache Efficiency Percentages (Target local+remote 100%) >> >> Buffer access - local cache %: 43.86 Buffer access - remote cache %: >> 2.09 Buffer access - disk %: 54.05 >> >> and in other node I observe >> >> >> Global Cache Efficiency Percentages (Target local+remote 100%) >> >> Buffer access - local cache %: 167.99 Buffer access - remote cache %: >> 51.42 Buffer access - disk %: -119.42 >> >> would appreciate any suggestion on why there is a 3 digit disk% on node >> 2 and a 3 digit buffer hit on node -1 >> >> >> Thanks >> >> Kart >> >> >> >> >> > > > -- > John Kanagaraj <>< > http://www.linkedin.com/in/johnkanagaraj > http://jkanagaraj.wordpress.com (Sorry - not an Oracle blog!) > ** The opinions and facts contained in this message are entirely mine and > do not reflect those of my employer or customers ** >