PostgreSQL 9.6 Beta 1 Released

http://www.postgresql.org/about/news/1668/

by linuxhiker • 10 years ago

174 40 10 years ago

postgresql.org

melor• 10 years ago

From the Release Notes:

Major enhancements in PostgreSQL 9.6 include:

Parallel sequential scans, joins and aggregates

Elimination of repetitive scanning of old data by autovacuum

Synchronous replication now allows multiple standby servers for increased reliability

Full-text search for phrases

Support for remote joins, sorts, and updates in postgres_fdw

Substantial performance improvements, especially in the area of improving scalability on many-CPU servers

koolba2• 10 years ago

Parallel query will probably win for sexiest new feature (rightfully so!) but remote apply is very useful in the real world. It will greatly simplify reading newly written data off replicas: http://michael.otacoo.com/postgresql-2/postgres-9-6-feature-...

dtech• 10 years ago

Could you elaborate on exactly what it is? Will it mean the named elements of queries will automatically be parallelized?

koolba2• 10 years ago

Postgres currently uses a single process per connection. That means at most one CPU core is used per query executing a connection. Parallel query allows breaking up query plans to allow multiple processes (and by extension cpu cores) to process a part of a query plan.

The classic example is a sequential scan, say for a COUNT(*) or SUM(foo). A single process would scan through all the blocks in order. A parallel scan would split the blocks into N buckets, scan them via N separate processes, and then combine the results.

pkaye• 10 years ago

Multiple worker thread will work together to do sequential scans, joins and aggregation. Some mentions here: http://rhaas.blogspot.com/2016/03/parallel-query-is-getting-...

But this is just a start and there are lots more opportunities to improve as mentioned here: https://wiki.postgresql.org/wiki/Parallel_Query_Execution

oskari2• 10 years ago

PG 9.6 Beta is available for testing at our Aiven.io Cloud Database service: http://blog.aiven.io/2016/05/help-test-postgresql-96-via-aiv...

pella2• 10 years ago

full Release Notes :

http://www.postgresql.org/docs/9.6/static/release-9-6.html

pella2• 10 years ago

and 9.7 have started planning

* [ "asynchronous and vectorized execution" ]

http://www.postgresql.org/message-id/CA+Tgmobx8su_bYtAa3Dgrq...

elchief3• 10 years ago

Isn't that like 8 months ahead of schedule?

pilif• 10 years ago

The Postgres beta periods are usually really, really, really long. Mid/End may is traditionally when the first beta comes out for a release in late autumn.

makmanalp• 10 years ago

As they should be! Enough time to know whether stuff breaks in real life or not, and to deal with fixing any issues that come up.

anarazel3• 10 years ago

Usually the target for the releases was September, not December/January like it ended up being for the last two. We're trying to get back to that.

qaq• 10 years ago

UPSERT from previous release plus Parallel sequential scans, joins and aggregates and Full text search for phrases once 9.6 is ready will make PG almost perfect :)

utternerd• 10 years ago

This is excellent, the read-balancing consistency is a huge feature, and one we've been waiting for as trying to do read balancing without it is jumping through way too many hoops (unless data consistency just isn't your thing).

desireco422• 10 years ago

I love new features in Postgres, but I hate upgrading. Transition, especially for dev environment is always way too complex and not obvious at all.

If there is one feature I wish PG had, it is recognizing old format db and offering one command that can in place upgrade damn db, without me googling it every time.

nunwuo• 10 years ago

If there is one feature I wish PG had, it is recognizing old format db and offering one command that can in place upgrade damn db, without me googling it every time.

So your having to Google for five minutes when doing a major version upgrade is the biggest flaw in modern postgres? Oh come on now.

P.S. pg_upgradecluster in Debian would probably do this for you without googling

jeffdavis• 10 years ago

It's not an unreasonable request, and certainly worth some effort to improve.

That being said, if upgrade is the biggest problem, that's great news!

desireco422• 10 years ago

Hey, I know it sounds a little spoiled, but when I am focused on something else, especially in development context, I could use some more automated way.

I am sorry you got downvoted, but as you can see, it is a genuine pain that software should do for us. On other hand, PG is fantastic DB and it is great I have this as a problem.

rpedela2• 10 years ago

You mean pg_upgrade?

http://www.postgresql.org/docs/9.5/static/pgupgrade.html

snuxoll3• 10 years ago

pg_upgrade is a pretty reasonable compromise, but it would be nice if an upgrade didn't require your entire database be taken offline for the duration. I can install a new MS SQL Server instance, attach a database from the old instance and be going in under a minute of downtime - this is literally the only pain point I have with Pq, but considering I don't typically upgrade EVERY release (I still have 9.4 instances that have no reason to be upgraded to 9.5 since the applications aren't in-house) it's not typically a huge deal.

agopaul2• 10 years ago

'Full-text search for phrases': what's the difference between the current full text search implementation and the one for phrases?

elchief3• 10 years ago

currently searching for 'new york' would match 'york new', as the parser doesn't understand phrases, but new version would let you match '"new york"' to 'new york' but not 'york new'

agopaul2• 10 years ago

That is a great addition then

rpedela2• 10 years ago

Does anyone know if parallel query execution just happens by default or do you have to tell PG that you want it?

jeltz• 10 years ago

You have to enable it by configuring the maximum number of workers per query, and then the query planner tries to figure out if the query would benefit from a parallel execution. This is the first release with parallelism so I would not be surprised if the query planner gets this wrong in some cases.

ormod_• 10 years ago

The features that I'll personally probably enjoy the most are really the FDW join pushdown work, parallel query. (though it's still early days for the parallel stuff)

..and the thing that's a killer feature for many larger databases, the freeze map. Not having to FREEZE things all the time is a godsend.

mistermann• 10 years ago

Could you possibly quickly explain what a freeze map is?

anarazel3• 10 years ago

Postgres uses a specific brand of MVCC (https://en.wikipedia.org/wiki/Multiversion_concurrency_contr...) where multiple versions of a row are stored in the heap. That's why there's vacuuming to remove those.

To avoid having to vacuum whole relations all the time there's the "visibility map", which keeps track of which blocks have no dirty rows; so they can be skipped during vacuum.

To understand which versions are visible postgres stores transaction-ids in the row headers; these are four byte wide. On systems with significant throughput, those don't last very long. So every now and then there's anti-wraparound vacuums; which replaces xids which are about to become "too old" with a special marker ("frozen").

The problem < 9.6 is that these anti-wraparound vacuums have to scan the whole table, thereby are a lot more expensive. These happen every 200 million xids by default (write transactions and/or savepoints), configurable up to ~2 billion. With the freeze map, that doesn't have to happen, only non-frozen pages have to be re-scanned.

kbenson• 10 years ago

Is there something specifically interesting in the 9.6 release that makes it more noteworthy than other releases? I enjoy reading PostgreSQL release announcements, as I myself haven't used it but have plans to do some testing with is when some time free up, but I'm a bit confused as to why a beta release announcement is getting so much attention.

anarazel3• 10 years ago

I guess because beta usually determines which features are going to be in the final release. So if you're looking what release to choose for a new version of your software, it might be more worthwhile to look at beta than the final release.

elchief3• 10 years ago

Any Postgres news is good news here. Same with OpenBSD. Just embrace it.

forkandwait• 10 years ago

I think that great parallel infrastructure would be worthy of a Postgres 10.0.

PostgreSQL 9.6 Beta 1 Released

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