On Tue, 2014-08-26 at 13:45 +0300, Heikki Linnakangas wrote:
Yeah. This patch in the current state is likely much much slower than unpatched master, except in extreme cases where you have thousands of connections and short transactions so that without the patch, you spend most of the time acquiring snapshots.
What else are you looking to accomplish with this patch during this 'fest? Bug finding? Design review? Performance testing?
Design review, mostly. I know the performance still sucks. Although if you can foresee some performance problems, aside from the extra CSNLOG lookups, it would be good to know.
I think for this commitfest, I've gotten as much review of this patch that I can hope for. Marking as "Returned with Feedback". But of course, feel free to continue reviewing and commenting ;-).
What is current state of this patch? Does community want CSN based snapshots?
Last email in lists was in August 2014. Huawei did talk about their further research on this idea at PGCon and promised to publish their patch in open source.
However, it isn't published yet, and we don't know how long we could wait for it.
Now, our company have resources to work on CSN based snapshots for 9.6. If Huawei will not publish their patch, we can pick up this work from last community version of this patch.
------ Alexander Korotkov Postgres Professional: http://www.postgrespro.com The Russian Postgres Company
