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"Richard Foote" <richard.foote_at_nospam.bigpond.com> wrote in message
news:cXdBi.27614$4A1.19426_at_news-server.bigpond.net.au...
> "Bob Jones" <email_at_me.not> wrote in message
> news:7d_Ai.4071$JD.3351_at_newssvr21.news.prodigy.net...
>> >> "Richard Foote" <richard.foote_at_nospam.bigpond.com> wrote in message >> news:seAAi.26732$4A1.22707_at_news-server.bigpond.net.au... >>> "Bob Jones" <email_at_me.not> wrote in message >>> news:mOnAi.236$ZA5.16_at_nlpi068.nbdc.sbc.com... >>>> >>>> "Richard Foote" <richard.foote_at_nospam.bigpond.com> wrote in message >>>> news:2_Wyi.24466$4A1.1328_at_news-server.bigpond.net.au... >>>>> >>>>> "Bob Jones" <email_at_me.not> wrote in message >>>>> news:kOtyi.50198$YL5.8637_at_newssvr29.news.prodigy.net... >>>>>> >>>>>> High BCHR is always better than low - provided everything else being >>>>>> equal. If BCHR is useless for the stated reasons, no other indicator >>>>>> would be useful. >>>>> >>>>> This I'm afraid is where you're fundamentally incorrect. >>>>> >>>>> A high BCHR can mean your database is on life support, struggling to >>>>> cope with exessive LIOs due to inefficient SQL with users staring at >>>>> an hourglass rather than returned data. >>>>> >>>>> A BCHR that has increased can mean your database has suddenly hit >>>>> significant performance issues. Or it can mean things have improved. >>>>> Or it can mean response times remain unaffected. >>>>> >>>>> A BCHR that has reduced can mean your database has suddenly hit >>>>> significant performance issues. Or it can mean things have improved >>>>> (yes, improved because that crippling transaction that was previously >>>>> performing poorly due to massively exessive LIOs has been fixed, >>>>> reducing the overall BCHR) . Or it can mean response times remain >>>>> unaffected. >>>>> >>>>> Not much of an indicator is it ? >>>>> >>>>> But saying that a BCHR is *always* better than a low is just plain >>>>> wrong wrong wrong ... >>>>> >>>> >>>> Didn't I repeatedly say "provided everything else being equal"? >>>> >>> >>> And how precisely do you determine that everything else indeed is equal >>> ? Most databases don't exactly remain equal ... >>> >> >> No, they do not. That's why you do not look at BCHR alone, as I have said >> before. >
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> >> >>> And when precisely do you check if everything else is equal with this >>> "very meaningful indicator" of yours ? When the BCHR increases ? When >>> the BCHR decreases ? When the BCHR remains the same ? >>> >> >> Try asking yourself the same questions about any other indicators you >> consider meaningful. The question here is not how to determine if >> everything else is equal. It is about whether BCHR means anything if >> everything else is equal. >
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Wow, that is a lot of questions for a simple concept. Apparently someone has not been paying attention. I am not sure why different people keep asking questions that are either irrelevant or have been answered. Received on Wed Aug 29 2007 - 21:27:10 CDT