Re: Sv: Re: Sv: Re: Sv: Re: Sv: Re: data-checksums

Greetings, * Andreas Joseph Krogh (andr...@visena.com) wrote: > Aha, so enabling CRC causes hint-bits to be written causing extra > WAL-logging, > which woudn't be the case without CRC enabled? > Thanks for pointing that out. Yes, having checksums enabled forces logging of hint bits. You can

Sv: Re: Sv: Re: Sv: Re: Sv: Re: data-checksums

På onsdag 10. januar 2018 kl. 01:01:26, skrev Andres Freund >: On 2018-01-10 00:25:08 +0100, Andreas Joseph Krogh wrote: > På tirsdag 09. januar 2018 kl. 23:42:45, skrev Rob Sargent < > robjsarg...@gmail.com >: >   >

Re: Sv: Re: Sv: Re: Sv: Re: data-checksums

On 2018-01-10 00:25:08 +0100, Andreas Joseph Krogh wrote: > På tirsdag 09. januar 2018 kl. 23:42:45, skrev Rob Sargent < > robjsarg...@gmail.com >: >   > >   On 01/09/2018 03:30 PM, Andreas Joseph Krogh wrote: > På tirsdag 09. januar 2018 kl. 23:06:06, skrev Andres

Re: Sv: Re: Sv: Re: data-checksums

On 01/09/2018 03:30 PM, Andreas Joseph Krogh wrote: På tirsdag 09. januar 2018 kl. 23:06:06, skrev Andres Freund >: Hi, On 2018-01-09 21:47:17 +0100, Andreas Joseph Krogh wrote: > Does PG use HW-accellerated crc if CPU supports

Sv: Re: Sv: Re: data-checksums

På tirsdag 09. januar 2018 kl. 23:06:06, skrev Andres Freund >: Hi, On 2018-01-09 21:47:17 +0100, Andreas Joseph Krogh wrote: > Does PG use HW-accellerated crc if CPU supports it[1]? Yes we do, for WAL checksums. The page checksums are a

Re: data-checksums

On 01/09/2018 12:22 PM, Andres Freund wrote: On 2018-01-09 20:04:04 +0100, Rakesh Kumar wrote: I also would like to believe that the hit is small, but when PG official document writes "noticeable performance penalty", it becomes difficult to convince management that the hit is small :-) Why

Re: data-checksums

On 2018-01-09 20:04:04 +0100, Rakesh Kumar wrote: > > > > I also would like to believe that the hit is small, but when PG > > > official document writes "noticeable performance penalty", it becomes > > > difficult to convince management that the hit is small :-) > > > > Why believe, when you can

Re: data-checksums

"On Tue, 9 Jan 2018 20:02:37 +0100, "Rakesh Kumar" wrote: >Hello Mr. Pedantic, > >> noticeable != huge. > >and noticeable != small/negligible either, at least from English >point of view. small != negligible. The word "noticable" does not imply any particular

Hi i like to unscribe me, sorry for the incovenient.

Em ter, 9 de jan de 2018 às 16:20, Jeff Janes escreveu: > On Tue, Jan 9, 2018 at 12:58 PM, Rakesh Kumar > wrote: > >> >> > That said, imv anyway, the performance hit is small and having checksums >> > is well worth it. >> >> I also would like to

Re: Getting started with first user.

Found out a way out. Logged in as *root*, and created a password for the *postgres* user. Then logged in as *postgres* and and ran "createuser -s me". Then logging in as *me*, ran "createdb" Agnar On 09/01/2018 17:13, Adrian Klaver wrote: On 01/09/2018 01:48 AM, Agnar Renolen wrote: I have

Re: data-checksums

> > I also would like to believe that the hit is small, but when PG > > official document writes "noticeable performance penalty", it becomes > > difficult to convince management that the hit is small :-) > > Why believe, when you can measure? yup doing that. But I still feel that PG

Re: data-checksums

Rakesh Kumar wrote: > > > That said, imv anyway, the performance hit is small and having > > checksums is well worth it. > > I also would like to believe that the hit is small, but when PG > official document writes "noticeable performance penalty", it becomes > difficult to convince management

Re: data-checksums

On 2018-01-09 18:58:41 +0100, Rakesh Kumar wrote: > > > That said, imv anyway, the performance hit is small and having checksums > > is well worth it. > > I also would like to believe that the hit is small, but when PG > official document writes "noticeable performance penalty", it becomes >

Re: data-checksums

> That said, imv anyway, the performance hit is small and having checksums > is well worth it. I also would like to believe that the hit is small, but when PG official document writes "noticeable performance penalty", it becomes difficult to convince management that the hit is small :-)

Re: data-checksums

Greetings, * Rakesh Kumar (rakeshkumar...@mail.com) wrote: > --data-checksums > Use checksums on data pages to help detect corruption by the I/O system that > would otherwise be silent. Enabling checksums may incur a noticeable > performance penalty. This option can only be set during

data-checksums

--data-checksums Use checksums on data pages to help detect corruption by the I/O system that would otherwise be silent. Enabling checksums may incur a noticeable performance penalty. This option can only be set during initialization, and cannot be changed later. If set, checksums are

Re: How Many Partitions are Good Performing

2018-01-09 18:15 GMT+01:00 Andrew Staller : > This is the blog post that Rakesh referenced: > https://blog.timescale.com/time-series-data-postgresql- > 10-vs-timescaledb-816ee808bac5 > > Please note, this analysis is done in the context of working with > time-series data,

RE: How Many Partitions are Good Performing

Thank you Rakesh and Andrew! We will not be doing time scaling but we have list of value based of which we will be partitioning the table and list is something around 7500 now. For short term we are thinking of putting around a thousand partitions and when PG11 releases we will go for each

Re: Supartitions in PGSQL 10

Virenda, is this time-series data you're working with? On Mon, Jan 8, 2018 at 4:12 PM, Kumar, Virendra wrote: > Team, > > > > Can you please let us know if Sub-partitions are supported in PGSQL > (declarative partitions) 10.1. If yes can it be list-list partitions.

Re: How Many Partitions are Good Performing

This is the blog post that Rakesh referenced: https://blog.timescale.com/time-series-data-postgresql-10-vs-timescaledb-816ee808bac5 Please note, this analysis is done in the context of working with time-series data, where 1000s of chunks is not uncommon because of the append-mostly nature of the

Re: Getting started with first user.

On 09/01/18 09:48, Agnar Renolen wrote: Then trying with the -U postgres option. root> createuser -U postgres me createuser: could not connect to database postgres: FATAL: Peer authentication failed for user "postgres" You need to specify the host as well, to force a TCP/IP connection:

Re: RES: help with generation_series in pg10

Márcio A. Sepp wrote: > > There is a generate_series() variant that can return dates (more > > precisely, timestamp with time zone). But what exactly would you like > > returned? > > In the past i use querys like this to generate some timestamp field: > select generate_series (1, 10),

Re: Getting started with first user.

On Tue, Jan 9, 2018 at 3:48 AM, Agnar Renolen wrote: > I have just installed PostGIS (Postgres9.6) on a Debian server using > apt-get. > > But I have problems doing anything: > > I installed as root, but trying doing things as my local user "me" > > me> createuser me >

RES: help with generation_series in pg10

> > how can i have the same in pg10 as i have had in pg 9.x? > > Move the function call to the FROM clause: > > select g, (g - 1) % 5 + 1 from generate_series(1, 10) g; thank you. That is exact what i need. > > I need it to date type to... if possible. > > There is a generate_series()

Getting started with first user.

I have just installed PostGIS (Postgres9.6) on a Debian server using apt-get. But I have problems doing anything: I installed as root, but trying doing things as my local user "me" me> createuser me createuser: could not connect to database postgres: FATAL: role "me" does not exist Then,

Re: Number of rows returned by Sort node

Vitaliy Garnashevich writes: > How, according to EXPLAIN ANALYZE, the Sort node could return more rows > as output (rows=767662), than it had for input from its child node > (rows=135627)? Unsurprising when it's the inner input of a merge join --- that reflects the

Number of rows returned by Sort node

Hi, How, according to EXPLAIN ANALYZE, the Sort node could return more rows as output (rows=767662), than it had for input from its child node (rows=135627)? ->  Merge Join  (actual time=1977.388..333626.072 rows=725757 loops=1)   ->  Index Scan using (actual

Re: help with generation_series in pg10

Márcio A. Sepp wrote: > how can i have the same in pg10 as i have had in pg 9.x? Move the function call to the FROM clause: select g, (g - 1) % 5 + 1 from generate_series(1, 10) g; > I need it to date type to... if possible. There is a generate_series() variant that can return dates (more