Re: Re: [COMMITTERS] pgsql: Avoid extra locks in GetSnapshotData if old_snapshot_threshold <

On Wed, Apr 13, 2016 at 12:25 PM, Robert Haas <robertmhaas@gmail.com> wrote:

> [test results with old_snapshot_threshold = 0 and 10]

From the docs:

| A value of -1 disables this feature, and is the default.

> Yuck.  Aside from the fact that performance tanks when the feature is
> turned on, it seems that there is a significant effect even with it
> turned off.

No evidence of that has been provided.  -1 is off; 0 is for testing
very fast expiration.

--
Kevin Grittner
EDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company