ICM Host name buffer cache parameter

Hello,
Does any body know about the ICM Host name buffer cache parameter?
I mean how long does it hold this value and cache refresh rate..
REgards,
Atul

Hello Prem,
Thanks for information.
I know that parameter and how to check.
My specific question is about hostname buffer cache rate and how long does it hold that value in buffer and refresh rate.
Regards,
Atul

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    Granule Size 16777216 No
    Maximum SGA Size 2634022912 No
    Startup overhead in Shared Pool 218103808 No
    Free SGA Memory Available 50331648

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    So i m back with my bunch of questions.I cant again ask a single because you know its a flow so i cant end up with single doubt.Thanks for your last reply.
    Yes amansir first doubt clear that was buffer will be inserted at MID point for this i got one nice document (PDF)names "All about oracle touch count algorithm by CRAIG A SHALLAHAMER".That was quite nice PDF allabout hot and cold buffer and buffer movments inside the LRU list.I am prettly much clear with that point.Thank you. and Incremental checkpoint i read from Harald.van.Breederode ppt a person from oracle.You have shared it on one of your thread.that was nice reference
    flicking through threads i came across term REPL and its variations REPL-AUX (thread was for Oracle 9i).Is this variation REPL-AUX deprecated in 10g So i i am not wrong For each work area two main lists that are LRU and CKPTQ exists??not more than that any other types?
    For non-RAC database Thread checkpoint is a Full checkpoint?
    I read about the incremental checkpointing Here incremental checkpointing in my words n brief.Incremental Checkpoints means write only some selected buffer from CKPTQ to Datafiles.FROM CKPTQ few Low orders RBA buffers are selected and chekcpointed *(Buffer will be checkpointed on many conditions)* and When the Next checkpoint occurs that buffers are flushed to disk.Now this thing *(Checkpointing few buffers and flushing them to disk)* can be multiple times within three seconds so after 3 seconds *(This is the 3 second concept i was asking in the starting of the thread,Can this time be changed if yes with which parameter)* the checkpoint RBA and Checkpoint*(the point upto which database buffer has flushed to disk)* will be updated in Control file header *(Datafile also)* by CKPT process.So that Checkpoint will be used for Instance recovery purpose.Which can dramatically down the instance recovery time.
    every 3 seconds control file is updated with checkpoint and that checkpoint is the point from where we have to start the recovery process in oracle from redo log.I m aware that incremental checkpointing is controlled by Fast_start_mttr_target prarameter and now it is autotuned for >10.2 but the smaller value i will keep the less time my instance will take.
    Is above two para right what i understood if wrong correct me??
    What i understand is after three seconds it will take some buffers from the CKPTQ ( from low RBA end ) and flush them to disk.apart from this many other conditions are there when Data will be flushed to disk.
    1) like CKPTQ is full.
    2)Process cant find a free buffer in LRU
    3)to advance checkpoint DBWR writes..
    Correct me if i m wrong?
    THANKS
    Kamesh
    Edited by: Kamy on May 2, 2011 10:55 PM

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