Re: ZFS and Postgresql - WASRe: Best OS for Postgres 8.2

But we still pay the penalty on WAL while writing them in the first 
place I guess .. Is there an option to disable it.. I can test how much 
is the impact I guess couple of %s but good to verify :-) )


Regards,
Jignesh


Alvaro Herrera wrote:
> Jignesh Shah escribió:
>
>   
>> Now comes the thing that I am still exploring
>> * Do we do checksum in WAL ? I guess we do .. Which means that we are 
>> now doing double checksumming on the data. One in ZFS and one in 
>> postgresql. ZFS does allow checksumming to be turned off (but on new 
>> blocks allocated). But of course the philosophy is where should it be 
>> done (ZFS or PostgreSQL).
>>     
>
> Checksums on WAL are not optional in Postgres, because AFAIR they are
> used to determine when it should stop recovering.
>
>