Subject | Re: [firebird-support] Re: FB database in RAM |
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Author | Thomas Steinmaurer |
Post date | 2011-08-10T05:52:33Z |
> We have been doing something similar to what you are trying without having to take the risk of running the DB in Ram, let me explain:hink you may be able to have the DB file actually cached by the OS (for reading purposes) instead of having FB doing so, then why risk it?
>
> In FB 2.1 64 bits (for Windows) we have been running the superserver version, with a very large DB. We configured the FB server to run about 2 GB of cache in ram, and set many other FB config variables to enhance performance. FB 2.1 64 bits has a limit of how much cache it can hold in ram, I think that is 2.5GB if I remember correctly. The limitation does not make any sense as the OS is 64 Bits and should be able to handle much more (from memory 32 bits OS can handle 2 potency of 32, been 4 GB, and 64 Bit OS would be 2 potency of 64, been a number I cannot even imagine). Any-ways, running the DB in ram is very risky, and you can avoid it by just placing a big cache on the FB configuration, and have a Server with 64 GB ram, and configure the RAID controller to allocate 100% priority to read cache. If you have a good RAID configuration, say 8 HDD on Raid 6, the reading speed would be 6 x HDD speed, and today you can buy SAS HDDs with very fast reading capabilities. I also t
>The maximum number of page buffers for Firebird 64-bit has been
> I am not sure if FB 2.1 64 for Linux has the same limitation in terms of the cache, it may be worth checking it,
increased in version 2.5 to (2^31 - 1).
--
With regards,
Thomas Steinmaurer
Upscene Productions
http://www.upscene.com
http://blog.upscene.com/thomas/
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