On Friday, 30.06.2006 at 12:11 +0800, Leo Huang wrote: > >ext3 flushes to disk every 5 seconds by default (see 'commit' > >interval in 'man mount') which is a safe, conservative setting but > >might hit performance. > The data is critical to us, so we must ensure every transaction is not > lost. I don't doubt that to be the case, however I was merely suggesting that the above ext3 setting might be responsible for the difference you see between Debian/ext3 and FreeBSD/ufs: I can't comment further since I have no experience of using FreeBSD/ufs. Since you're interested in finding out where the performance bottleneck is, you could at least benchmark the difference (using non-critical data): if, for example, FreeBSD/ufs flushing data to disk every *20* seconds (I have no idea what the real value is), that would be part of the explanation of your problem. It's certainly worth investigating, if you have the opportunity. For what it's worth, it is usually safe to raise the ext3 commit interval on a system, at least up to the period of time which is covered by UPS power support. Dave. -- Please don't CC me on list messages! ... Dave Ewart - davee@sungate.co.uk - jabber: davee@jabber.org All email from me is now digitally signed, key from http://www.sungate.co.uk/ Fingerprint: AEC5 9360 0A35 7F66 66E9 82E4 9E10 6769 CD28 DA92
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