Subject Re: FB database in RAM
Author karolbieniaszewski
--- In, Kjell Rilbe <kjell.rilbe@...> wrote:
> Den 2011-08-03 14:25 skrev Kjell Rilbe såhär:
> > For performance reasons we're considering a setup where our 50+ Gbyte
> > Firebird database would reside on a RAM-disk.
> After the discussion here as well as a discussion between me and my
> partner and after getting some info on the cost of a server with 60+
> Gbyte RAM, we are now aiming at a solution where only the relevant parts
> of our ~60 Gbyte database will be "published" to a separate and much
> smaller database that will be structured and indexed for optimal search
> performance. This smaller DB will be placed on SSD or RAM disk instead
> of the huge one.
> Both bases will be accessed and maintained by the same web application,
> enabling us to do unusual complicated searches that are not possible in
> the fast search database, but always do as much as possible in the fast
> one, and then do the rest in the "back end" slower system.
> The large DB will, for the time being, stay on a regular RAID1 volume
> with 15 krpm SCSI disks.
> It's been an interesting discussion and I hope it will keep going a
> little while longer, e.g. regarding disk controllers with SSD cache.
> Regards,
> Kjell
> --
> --------------------------------------
> Kjell Rilbe
> DataDIA AB
> E-post: kjell@...
> Telefon: 08-761 06 55
> Mobil: 0733-44 24 64


you say that cost of 64 GB RAM is big? Now RAM are cheaper and cheaper ;-)
How much you must pay for good SCSI Drivers 15krpm and SCSI controller?
And how offen do you must replace disc by new one? Two years of work is for me max.

And about discusion of big cache with regular disc this is good point but if you have DB in RAM then default value from installation is good - you read from RAM and store data in cache also in RAM :)

Karol Bieniaszewski