Re: [?] no logging mode

ok,
excuse me;

i have increased the log_buffer parameter because i have 'redo log space requests = 381'
and i have read that the solution for this problem is to increase log_buffer;
i have set nologging mode for my tablespaces to increase performance because i have very lot transactions;

thanks.

"Howard J. Rogers" <hjr_at_dizwell.com> ha scritto nel messaggio news:4019193b$0$28870$afc38c87_at_news.optusnet.com.au...
>
> "gp" <gieppetto_at_tiscali.it> wrote in message
> news:bvb2vl$ri1$1_at_carabinieri.cs.interbusiness.it...
> > do you think that i must increase log_buffer parameter ?
> > (now it is 16 MB)
> > thanks.
> > Ciao.
>
> Lord! The log_buffer should never, ever, ever need to be bigger than 1MB.
> Ever.
>
> Well, except on those extremely rare occasions when maybe 3 or 4MB might
be
> in order. But those are extremely rare, so I'd prefer to make your life
> easier by sticking with 'never, ever'.
>
> Really. The log_buffer is (or ought to be) tiny, because redo is tiny.
> You're talking about a few hundred bytes at most being generated per row
> modification, and with in-built cleansing mechanisms such as the flush at
> 1/3rd full, every commit and before DBWR to keep the persistence space
> demands on the log buffer down to negligible levels. It's not like the
> buffer cache, that deals with blocks of data in the multi-thousands of
bytes
> sizes, where blocks hang around for quite long times, where DBWR flushes
> comparatively rarely and so on. Buffer Cache big, log buffer tiny.
>
> I suppose the real question is: what makes you think you might need a log
> buffer of 16MB, and what makes you do daft things like (attempt to) turn
all
> tablespaces into nologging mode? It wouldn't be because you are suffering
> from log buffer space wait events or something, would it? Because those
are
> not the cures for that particular problem.
>
> Tell you what: tell us why you thought you needed to do these things
first,
> and then we can have a go at explaining what the real cures are. But 16MB
> for a log buffer is way, way too much.
>
> Regards
> HJR
> --
> ------------------------------------
> Oracle insights at www.dizwell.com
> ------------------------------------
>
>
Received on Thu Jan 29 2004 - 09:54:53 CST