Thread: Serializable read and blocking

Serializable read and blocking

From
Rakesh Kumar
Date:
As per this blog post

http://bonesmoses.org/2016/07/29/pg-phriday-constipated-connections/

I have a question which I asked there too, but unfortunately did not
receive any answer.

The question is re the following claim:

- Readers do not block readers.
- Readers do not block writers.
- Writers do not block readers.
- Writers may block writers.


Are the above statements true even with SET TRANSACTION SERIALIZEABLE mode.
I am specifically interested in the 3rd condition (- Writers do not
block readers.)

thanks


Re: Serializable read and blocking

From
Kevin Grittner
Date:
On Thu, Aug 11, 2016 at 7:11 AM, Rakesh Kumar
<rakeshkumar464a3@gmail.com> wrote:

> The question is re the following claim:
>
> - Readers do not block readers.
> - Readers do not block writers.
> - Writers do not block readers.
> - Writers may block writers.
>
>
> Are the above statements true even with SET TRANSACTION SERIALIZEABLE mode.
> I am specifically interested in the 3rd condition (- Writers do not
> block readers.)

Yes.

https://wiki.postgresql.org/wiki/SSI

http://vldb.org/pvldb/vol5/p1850_danrkports_vldb2012.pdf

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