Re: Overhead cost of Serializable Snapshot Isolation

Greg Sabino Mullane wrote:
-- Start of PGP signed section.
> > If the normal default_transaction_isolation = read committed and all
> > transactions that require serializable are explicitly marked in the
> > application then there is no way to turn off SSI without altering the
> > application. That is not acceptable, since it causes changes in
> > application behaviour and possibly also performance issues.
> 
> Performance, perhaps. What application behavior changes? Less 
> serialization conflicts?
> 
> > We should provide a mechanism to allow people to upgrade to 9.1+
> > without needing to change the meaning and/or performance of their
> > apps.
> 
> That ship has sailed.

Simon seems to value backward-compatibility more than the average
hackers poster.  The lack of complaints about 9.1 I think means that the
hackers decision of _not_ providing a swich was the right one.

-- 
  Bruce Momjian  <bruce@momjian.us>        http://momjian.us
  EnterpriseDB                             http://enterprisedb.com

  + It's impossible for everything to be true. +