Re: SetBufferCommitInfoNeedsSave and race conditions

Where are we on this?

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Gregory Stark wrote:
> "Simon Riggs" <simon(at)2ndquadrant(dot)com> writes:
>
> > I'd guess that storing 8 per page would be optimal, so each stored xid would
> > track 4,000 transactions - probably around 1 sec worth of transactions when
> > the feature is used.
>
> This is something we can experiment with but I suspect that while 8 might be
> sufficient for many use cases there would be others where more would be
> better. The cost to having more lsns stored in the clog would be pretty small.
>
> On TPCC which has longer transactions on moderate hardware we only see order
> of 1,000 txn/min. So a setting like 128 which allows a granularity of 256
> transactions would be about 15s which is not so much longer than the xmin
> horizon of the 90th percentile response time of 2*5s.
>
> --
> Gregory Stark
> EnterpriseDB http://www.enterprisedb.com
>
>
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--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://www.enterprisedb.com

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