Hi All ,

Can you please help me out with the following questions .



Our application is running on Postgres 7.4.X . I agree that this is a very
old version of Postgres and we should have upgraded . The issue that we
faced is that



1 . There was a system crash due to a hardware failure .



2 . When the system came up , we tried to insert a few records into the
database . However at this point in time we saw that Postgres was taking a
lot of CPU & memory .



Around 42% CPU consumption . This was a cause of concern .



3 . We re-indexed the database and it helped reduce the cpu & memory
consumption .



My question is



A ) Isn’t Postgres database resilient enough to handle hardware system
failure ? or it sometime results in a corrupt index for its tables ? I read
on the Postgres site that hardware failure can cause corrupt indexes .
Besides this are there any other scenario which may result in such
corruption .

B) If there has been improvement / enhancements done by Postgres regarding
the way it handles corrupt indexes can you please pass me more information
about the bug Id or some documentation on it ? Our application does not do
any REINDEXING . I am in a dilemma if we should seriously incorporate it in
our application .



I ideally want to push to a higher version of Postgres . If I can prove that
there will be significant performance benefits and that crashes won’t occur
then I will be able to present a strong case .


Since my question is related to Performance & Data corruption i saw on the
Postgres site that i should provide the following information


Addition Info :


CPU manufacturer and model : Intel's Itanium Processor

Do you use a RAID controller? yes


PCIe SAS SmartArray P410i RAID Controller

PCIe SAS SmartArray P411 RAID Controller


Is is Write back caching enabled ?

    Total Cache Size (MB)............... 144
    Read Cache........................ N/A

    Write Cache....................... N/A

No of disks : 4


Have you *ever* set fsync=off in the postgresql config file?

#fsync = true                   # turns forced synchronization on or off

I never changed it .


Have you had any unexpected power loss lately? Replaced a failed RAID disk?
Had an operating system crash?  Yes system crashed had occured .


Hope this information helps .


Regards,

Sumeet

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