Re: Acclerating INSERT/UPDATE using UPS - Mailing list pgsql-hackers

Joshua,

I appreciate your great suggestion!
It is great honor for me if Sigres will be merged to PostgreSQL.
Since the changes of Sigres from PostgreSQL-8.2.1 are not many,
and moreover, all of changes are surrounded with #ifdef SIGRES --- #endif,
incorporating Sigres into PostgreSQL would be easy.

However, Sigres modifies WAL which is the most important point of DBMS
on stability.
Although I myself could not find any bugs in Sigres, I am really afraid
of it. It a bug exists on Sigres, it puts everyone to huge
inconvenience... Therefore, before incorporating Sigres into PostgreSQL,
the code must be checked, and the behaviors of Sigres must be checked
carefully. Since PostgreSQL is a famous and wide spread software, I
strongly want to avoid losing its great reputation. Unfortunately in
Japan, I do not know any WAL hackers except for a friend of mine, and he
is too busy to check Sigres. So, if pgsql-hackers checks Sigres, I am
really happy.

Best Regards,

-- Hideyuki

Joshua D. Drake wrote:
> Hideyuki Kawashima wrote:
>   
>> Joshua,
>>     
>
> :)
>
>   
>> The reason why I made the Sigres is, the advances of recent non volatile
>> memories. Just now we do not usually use non volatile memories. But in
>> the near future, situation would change. I think if a non volatile
>> memories can be considered as a persistence device, PostgreSQL WAL
>> mechanism should be modified.
>> However, I do not use such devices usually. Thus I made Sigres which
>> requires UPS.
>>     
>
> This is actually very interesting. We (www.commandprompt.com) have had
> several customers ask us how we can make PostgreSQL more reasonable
> within a flash environment.
>
> I agree with you that in the future you will see many such databases
> including PostgreSQL living on these devices.
>
> Tom? What do you think? Is there some room for movement here within the
> postgresql.conf to make something like sigres usable within PostgreSQL
> proper?
>
>   
>> Currently I have just ignored XLogWrite and WALWriteLock, but a friend
>> of mine (a Japanese great hacker of PostgreSQL) has more idea to improve
>> WAL if a battery supplied memory can be considered as a persistent device.
>>
>>     
>
> We are coming up very quickly on a feature freeze for the next version
> of PostgreSQL. If... we can has something out quickly enough and in a
> thought out fashion, the hackers may be willing to accept a patch for
> 8.3.. If not there is always 8.4..
>
> Sincerely,
>
> Joshua D. Drake
>
>
>
>
>   

-- 
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