Thread: Replication options

Replication options

From
"Simon Windsor"
Date:

Hi

 

I am used to using Oracle (15 years) and MySQL(5 years), but I am planning to move an existing application from MySQL to Postgres. The reasons are very simple,

 

  • New requirements means we need views, or a significant re-write
  • Better query/index performance essential.
  • Postgres and MySQL share a very common implementation of SQL-92, and what is missing can easily be implanted in functions

 

The only negative issue is replication. I have checked several Postgres Replication options and unsure which way to go. Can anyone recommend a replication option that meets the following:

 

  • Does not use triggers. Usually slow, and one action that modifies several records, can trigger many actions on slaves/peers.
  • Does use WAL, or other log, so that SQL DDL/DML is copied to slave/peer, rather than the result of the DDL/DML.
  • Must provide master-master and master-slave replication
  • Simple to configure and maintain

 

Many Thanx

 

Simon Windsor

Eml: simon.windsor@cornfield.org.uk

Tel: 01454 617689

Mob: 07960 321599

 


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Re: Replication options

From
Andrew Rawnsley
Date:
On Feb 19, 2004, at 1:24 PM, Simon Windsor wrote:

> Hi
>
>  
>
> I am used to using Oracle (15 years) and MySQL(5 years), but I am
> planning to move an existing application from MySQL to Postgres. The
> reasons are very simple,
>
>  
>     •     New requirements means we need views, or a significant re-write
>     •     Better query/index performance essential.
>     •     Postgres and MySQL share a very common implementation of SQL-92,
> and what is missing can easily be implanted in functions
>
>  
>
> The only negative issue is replication. I have checked several
> Postgres Replication options and unsure which way to go. Can anyone
> recommend a replication option that meets the following:
>
>  
>     •     Does not use triggers. Usually slow, and one action that modifies
> several records, can trigger many actions on slaves/peers.
>     •     Does use WAL, or other log, so that SQL DDL/DML is copied to
> slave/peer, rather than the result of the DDL/DML.

I think only Mammoth's ships WAL logs. Josh?

>     •     Must provide master-master and master-slave replication

I don't think any of the solutions will do master-master.

>     •     Simple to configure and maintain
>
>  
>
> Many Thanx
>
>  
>
> Simon Windsor
>
> Eml: simon.windsor@cornfield.org.uk
>
> Tel: 01454 617689
>
> Mob: 07960 321599
>
>  
>
> --
>  This message has been scanned for viruses and
> dangerous content by MailScanner, and is
> believed to be clean.
> Mailscanner thanks transtec Computers for their support.
--------------------

Andrew Rawnsley
President
The Ravensfield Digital Resource Group, Ltd.
(740) 587-0114
www.ravensfield.com


Re: Replication options

From
"Joshua D. Drake"
Date:
>>     •     Does not use triggers. Usually slow, and one action that
>> modifies several records, can trigger many actions on slaves/peers.
>>     •     Does use WAL, or other log, so that SQL DDL/DML is copied to
>> slave/peer, rather than the result of the DDL/DML.
>
>
> I think only Mammoth's ships WAL logs. Josh?

No we do not ship WAL logs. We ship our own transaction logs. One of the
reasons we do this is so you can bring up new slaves live. We do not
support replication of the SQL DDL but you do not need to stop the
replication or stop the database to add tables to the replicated list.


>>     •     Must provide master-master and master-slave replication
>
>
> I don't think any of the solutions will do master-master.

Only that new clusgres thing from LinuxLabs but I would have to see it
in production before I would get anywhere near it.

Sincerely,

Joshua D. Drake




>
>>     •     Simple to configure and maintain
>>
>>
>>
>> Many Thanx
>>
>>
>>
>> Simon Windsor
>>
>> Eml: simon.windsor@cornfield.org.uk
>>
>> Tel: 01454 617689
>>
>> Mob: 07960 321599
>>
>>
>>
>> --
>>  This message has been scanned for viruses and
>> dangerous content by MailScanner, and is
>> believed to be clean.
>> Mailscanner thanks transtec Computers for their support.
>
> --------------------
>
> Andrew Rawnsley
> President
> The Ravensfield Digital Resource Group, Ltd.
> (740) 587-0114
> www.ravensfield.com
>
>
> ---------------------------(end of broadcast)---------------------------
> TIP 8: explain analyze is your friend


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Re: Replication options

From
"Merrall, Graeme"
Date:
 
 

The only negative issue is replication. I have checked several Postgres Replication options and unsure which way to go. Can anyone recommend a replication option that meets the following:

 

  • Does not use triggers. Usually slow, and one action that modifies several records, can trigger many actions on slaves/peers.
  • Does use WAL, or other log, so that SQL DDL/DML is copied to slave/peer, rather than the result of the DDL/DML.
  • Must provide master-master and master-slave replication
  • Simple to configure and maintain

 

 

Is there any comparative analysis of the different pgsql replication systems out there? SO far I can think of erserver (free + payware),  mammoth, dbbalancer, pgreplication. Have I missed any?

If such a thing doesn't exist I could cobble few servers together and have a crack.

 

Cheers,

 Graeme