Re: Synch Rep v5

On Sat, 2009-01-10 at 19:16 +0900, Fujii Masao wrote:

> I attached the updated version of Synch Rep patch (v5) on wiki.
> The description of "User Overview" is also already updated.
> http://wiki.postgresql.org/wiki/NTT%27s_Development_Projects#Synch_Rep

Looks good on initial read of Wiki. Few minor comments:

The advantage of doing things this way is that the base backup can take
place any way the user chooses, so potentially much faster than using a
single session.

I notice we use the same settings for keepalives. We may need that to be
a second set of parameters.

Progress reporting will be easier with HS, so you are right to leave
that alone.

Don't understand: "Completely automated catching up; User has to carry
out some procedure manually for making the standby catch up."

Multiple standby is still possible, but just using old file based
mechanisms. We would need to be careful about use of %R in that case.

I believe the max delay is 2* wal_sender_delay.

I like the way recovery_trigger_file avoids changing pg_standby, but I
guess we still need to plug that gap also one day. But does patch 10
also have the other mechanism?

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Simon Riggs www.2ndQuadrant.com
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