Re: [Firebird-devel] FB 2.1 64bit and memory usage ??

[Alexandre B. S. <ib...@th...>]

Dmitry Yemanov wrote:
> Tom Miller wrote:
>   
>> We have servers with 6 GB of memory.  Ideally we would like to leave 1
>> GB for Linux and have FB use the other 5GB.  Will the 64bit version do
>> this?  i.e. break the 2gb memory barrier?
>>     
>
> While the 64-bit builds can use more than 2GB of memory, it's true for 
> the overall memory usage only. But the page cache size is limited by 
> 128K pages (512MB-2GB, depending on the page size). It's not a problem 
> for Classic, but it's going to bite you if you're using SuperServer.
>
> I think we should increase the limit, at least for the 64-bit builds. 
> Objections anyone?
>
>
> Dmitry
>   


What would happen if one defines more than 128k pages in 32 bit builds ? 
just ignore and use 128k or abort with a invalid configuration parameter ?

There are any plans to provide bigger page sizes ? (32kb, 64kb)

A kind of "support question" but anyone has any idea of the effects of 
"double caching" ? FB uses RAM to cache MRU pages in it's own cache, OS 
uses RAM to hold MRU disk clusters/blocks, wouldn't the "hot" disk 
blocks tend to be the same data as the hot database pages on a machine 
that runs only FB ? (I think this is the kind of use when one wishes FB 
to use massive amounts of RAM)

see you !

-- 
Alexandre Benson Smith
Development
THOR Software e Comercial Ltda
Santo Andre - Sao Paulo - Brazil
www.thorsoftware.com.br