On Thu, Sep 8, 2011 at 6:46 PM, Robert Haas wrote:
> I'm not convinced it's anywhere near that easy. For one thing, on at
> least one big server I'm playing with, memory latency on shared memory
> is vastly higher (like >10x!) than on backend-local memory due to NUMA
> effects.
I wonder if both
Ants Aasma writes:
> On Thu, Sep 8, 2011 at 5:28 PM, Robert Haas wrote:
>> 1. A backend can have lots of snapshots, potentially requiring an
>> unbounded amount of shared memory. We can't accommodate that.
> If PostgreSQL gets POSIX shared memory capability at some point in the
> future, would
On Thu, Sep 8, 2011 at 11:33 AM, Ants Aasma wrote:
> On Thu, Sep 8, 2011 at 5:28 PM, Robert Haas wrote:
>> On Thu, Sep 8, 2011 at 9:26 AM, Ants Aasma wrote:
>>> When go try to find the new csnmin
>>> and discover that a backend has a csnmin that is too old, we go through
>>> the snapshots of tha
On Thu, Sep 8, 2011 at 5:28 PM, Robert Haas wrote:
> On Thu, Sep 8, 2011 at 9:26 AM, Ants Aasma wrote:
>> When go try to find the new csnmin
>> and discover that a backend has a csnmin that is too old, we go through
>> the snapshots of that backend and convert every snapshot under the
>> desired
On Thu, Sep 8, 2011 at 9:26 AM, Ants Aasma wrote:
> When go try to find the new csnmin
> and discover that a backend has a csnmin that is too old, we go through
> the snapshots of that backend and convert every snapshot under the
> desired csnmin to a traditional snapshot.
I thought about somethi
Hi,
I have been thinking about how to handle long running transactions with
Robert’s commit sequence number (CSN) idea.
http://archives.postgresql.org/message-id/CA%2BTgmoaAjiq%3Dd%3DkYt3qNj%2BUvi%2BMB-aRovCwr75Ca9egx-Ks9Ag%40mail.gmail.com
I just started to go through transaction management code
