Re: PostgreSQL insights: does it use DMA?

Scott, regardless of operating system support for DMA, an application
may not benefit from it if it doesn't use appropriate system calls.

PostgreSQL is implemented mostly in C, so I do not know whether it
needs to use special procedure calls, however this is true, for
example, for Java
http://www.ibm.com/developerworks/library/j-zerocopy/

2011/9/9 Scott Marlowe <scott(dot)marlowe(at)gmail(dot)com>:
> On Fri, Sep 9, 2011 at 11:55 AM, Antonio Rodriges <antonio(dot)rrz(at)gmail(dot)com> wrote:
>> Hello,
>>
>> Does anyone know whether PostgreSQL uses DMA (Direct Memory Access) in
>> certain cases to improve networking IO performance?
>>
>> I mean "simple" query is which doesn't require any CPU processing, for ex
>> SELECT column_a FROM table_b WHERE date = "2001-10-05"
>>
>> I need this to devise the best logic for the system with PostgreSQL as
>> a layer. Certainly I could study PostgreSQL sources or test it with a
>> simple application but I hope PostgreSQL experts are aware of this
>> feature.
>
> That's all up to your hardware and OS, not postgresql
>

--
Kind regards,
Antonio Rodriges