SAS 15k in RAID 0, i thing it's not so bad :)

i have comit on just one row that sometime take more than 15 secondes !!!!!! on now it's a nightmire because every 2 or 3 days the database become corrupt !

--- In firebird-support@yahoogroups.com, "Slavomir Skopalik" <skopalik@...> wrote:
>
> Hi, I didn't read info about your HW, but it seems to be standart PC with
> IDE (SATA) HDD.
> You can use HW RAID controler with large cache with batery backup (write
> back cache enabled).
>
> Also you have to have separate HDD (RAID 1 on real server) for DB files.
>
> Other ways means change your DB design or application.
> One tip: insert more records together without commit and perform only one
> commit at the end.
>
> Slavek
> Ing. Slavomir Skopalik
> Jednatel spolecnosti
> Elekt Labs s.r.o.
> Chaloupky 158
> 783 72 Velky Tynec
> Czech Republic
> --------------------------------------------
> Mobil: +420 724 207 851
> icq:199 118 333
> e-mail:skopalik@...
> http://www.elektlabs.cz <http://www.elektlabs.cz/>
>
>
>
>
>
>
> thanks ivan,
>
> yes i just try with force write off, and yes now i have
>
> Time to execute the sql: 16 ms
> Indexed Read: 117
> Non Indexed Read: 0
> Inserts: 30
> Updates: 0
> Deletes: 30
> Time to commit the data: 0
>
> the commit is now very fast (in apparence) but in fact it's not really help
> because if i execute five time the query, on the fifth (exactly on every
> fifth execute) i have
>
> Time to execute the sql: 0 ms
> Indexed Read: 117
> Non Indexed Read: 0
> Inserts: 30
> Updates: 0
> Deletes: 30
> Time to commit the data: 3202
>
> :( it's mean if i m unlucky when i execute the query that it is the flush
> time i loose :( i was thinking that the flush was done by a separate thread
> and not by a "commit" thread
>
> do you have any other idea how to speed up the commit ? the index is multi
> column (6 at max) ... do you thing reduce the number of column can help ?
>
> thanks you by advance
>
> --- In firebird-support@ <mailto:firebird-support%40yahoogroups.com>
> yahoogroups.com, "Ivan Prenosil" <Ivan.Prenosil@> wrote:
> >
> > > when i execute some SQL, the time to execute the sql is very fast (16ms)
> but the time to commit the data is very very slow (2293
> > > ms, even some time more than 10 secondes !)
> > >
> > > Time to execute the sql: 16 ms
> > > Indexed Read: 117
> > > Non Indexed Read: 0
> > > Inserts: 30
> > > Updates: 0
> > > Deletes: 30
> > > Time to commit the data: 2293
> > >
> > > the tables where the record was inserted/deleted have lot of indexes
> (around 30 index by table, and around 10 columns by table)
> >
> > On commit, every page in FB cache changed by your transaction
> > (and depending) must be written to disk.
> > FB keeps database in consistent state by writing pages in specific order,
> > and setting Forced Writes On prevents OS from optimizing those writes.
> > So, modifying tables with lots of indexes like yours causes
> > heavy disk trashing and so is slow.
> > You should reduce number of indexes,
> > or (if you can take that risk) turn Forced Writes Off.
> >
> > Ivan
> > http://www.volny <http://www.volny.cz/iprenosil/interbase/>
> cz/iprenosil/interbase/
> >
>
>
>
>
>
> [Non-text portions of this message have been removed]
>