Should OS/FileSystem caching be write-through?

I have a question. I use Ubuntu. Should I mount my filesystem (which holds BDB's content) with "-o sync" option? That is, should my file system cache be write-through?
I have this question because, if I turn on the logging feature in Berkeley DB but let the file system cache be write-back, I don't exactly know if the log is properly flushed to the disk or not.

Thanks George. I agree that mature applications would be better off mounting their filesystem with "-o sync" option.
But here is a thing: I ran an example test case where I inserted 10 million key-value pairs with logging enabled, and saw that the average response time per insertion was 10 milli seconds, and I did the same experiment with logging disabled and saw that it too took 10 milliseconds per insertion on an average.
For the experiment with logging enabled, I create the environment with DB_INIT_LOG and DB_INIT_TXN flags but don't surround the insertion requests with txn_begin() and txn->commit(). I guess this way of doing insertions is called autocommit. I am hoping I am doing this experiment right.
Thanks for the pointers about set_flags() and DB_TXN_NOSYNC, I am going to look them up.

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    - or if the database went down (noticeable from the failure), then it is up to you whether you send a confirmation which also mentions that it is not persisted to disk yet, or not at all
    Best regards,

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    HP Pavilion mMedia Center TV m7664x Desktop PC Support;dlc=en&amp;docname=c00757531&amp;lc=en&amp;prod...
    Your HP computer case (Code Name: Grand Canyon) is designed for microATX motherboards.
    HP used the Hauppauge Computer Works internal WinTV cards, in this time period.
    SOME of these OEM cards, such as the HVR-1260 model, were specially built for HP.
    In looking at the Windows XP Drivers, for this computer, it shipped in Fall 2006 with:
    1.) Conexant Falcon II TV tuner solution OR
    2.) Hauppauge WinTV PVR PCI II 23xxx, 25xxx and 26xxx TV tuner solutions.
    Open up your computer -- the TV Tuner is an ADD-IN Expansion Card.
    You can contact Hauppage for additional support information.
    Hauppage Computer Works -- WinTV products
    Ceton Infinitv products

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