Re: [SPAM] Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-08-03 Thread Francisco Olarte
Hi Moreno: On Wed, Aug 3, 2016 at 1:07 PM, Moreno Andreo wrote: It's already been answered, but as it seems to be answering a chunk of my mail... > Should I keep fsync off? I'd think it would be better leaving it on, right? Yes. If you have to ask wether fsync should be on, it should. I mean,

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-08-03 Thread Moreno Andreo
Il 03/08/2016 18:01, Jeff Janes ha scritto: On Thu, Jul 28, 2016 at 6:25 AM, Moreno Andreo wrote: Hi folks! :-) I'm about to bring up my brand new production server and I was wondering if it's possible to calculate (approx.) the WAL directory size. I have to choose what's better in terms of cos

Re: [GENERAL] WAL directory size calculation

2016-08-03 Thread Jeff Janes
On Thu, Jul 28, 2016 at 6:25 AM, Moreno Andreo wrote: > Hi folks! :-) > I'm about to bring up my brand new production server and I was wondering if > it's possible to calculate (approx.) the WAL directory size. > I have to choose what's better in terms of cost vs. performance (we are on > Google C

Re: [GENERAL] WAL directory size calculation

2016-08-03 Thread Jeff Janes
On Thu, Jul 28, 2016 at 6:33 AM, David G. Johnston wrote: > On Thu, Jul 28, 2016 at 9:25 AM, Moreno Andreo > wrote: >> >> I've read somewhere that the formula should be 16 MB * 3 * >> checkpoint_segment in size. > > [...] > >> >> Using the above formula I have: >> 16 MB * 3 * 1 GB >> that lea

Re: [SPAM] Re: [SPAM] Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-08-03 Thread Moreno Andreo
Il 03/08/2016 14:12, Michael Paquier ha scritto: On Wed, Aug 3, 2016 at 8:07 PM, Moreno Andreo wrote: Should I keep fsync off? I'd think it would be better leaving it on, right? >From the docs: https://www.postgresql.org/docs/9.6/static/runtime-config-wal.html#RUNTIME-CONFIG-WAL-SETTINGS Whil

Re: [SPAM] Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-08-03 Thread Michael Paquier
On Wed, Aug 3, 2016 at 8:07 PM, Moreno Andreo wrote: > Should I keep fsync off? I'd think it would be better leaving it on, right? >From the docs: >https://www.postgresql.org/docs/9.6/static/runtime-config-wal.html#RUNTIME-CONFIG-WAL-SETTINGS While turning off fsync is often a performance benefi

Re: [SPAM] Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-08-03 Thread Moreno Andreo
Il 29/07/2016 17:26, Francisco Olarte ha scritto: Hi: On Fri, Jul 29, 2016 at 10:35 AM, Moreno Andreo wrote: After Andreas post and thinking about it a while, I went to the decision that it's better not to use RAM but another persistent disk, because there can be an instant between when a WAL

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-08-01 Thread Moreno Andreo
Il 29/07/2016 15:30, David G. Johnston ha scritto: On Fri, Jul 29, 2016 at 7:08 AM, Moreno Andreo wrote: ​R​

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread Francisco Olarte
Hi: On Fri, Jul 29, 2016 at 10:35 AM, Moreno Andreo wrote: > After Andreas post and thinking about it a while, I went to the decision > that it's better not to use RAM but another persistent disk, because there > can be an instant between when a WAL is written and it's fsync'ed, and if a > failur

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread Moreno Andreo
To: FarjadFarid(ChkNet) ; pgsql-general@postgresql.org Subject: Re: [SPAM] Re: [GENERAL] WAL directory size calculation   Il 29/07/2016 11:44, FarjadFarid(ChkNet) ha scritto:

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread David G. Johnston
On Fri, Jul 29, 2016 at 7:08 AM, Moreno Andreo wrote: > ​R​ > egarding backups I disagree. Files related to database must be consistent > to the database itself, so backup must be done saving both database and > images. > ​I'd suggest you consider that such binary data be defined as immutable. T

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread FarjadFarid(ChkNet)
l.org <mailto:pgsql-general-ow...@postgresql.org> [mailto:pgsql-general-ow...@postgresql.org] On Behalf Of Moreno Andreo Sent: 29 July 2016 10:19 To: pgsql-general@postgresql.org <mailto:pgsql-general@postgresql.org> Subject: Re: [SPAM] Re: [GENERAL] WAL directory size calculation Il

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread FarjadFarid(ChkNet)
. They also distributed servers around the world. Hope this helps. From: Moreno Andreo [mailto:moreno.and...@evolu-s.it] Sent: 29 July 2016 12:08 To: FarjadFarid(ChkNet) ; pgsql-general@postgresql.org Subject: Re: [SPAM] Re: [GENERAL] WAL directory size calculation Il 29/07/2016

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread Moreno Andreo
[SPAM] Re: [GENERAL] WAL directory size calculation   Il 29/07/2016 10:43, John R Pierce ha scritto:   Aside of this

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread FarjadFarid(ChkNet)
luck. From: pgsql-general-ow...@postgresql.org [mailto:pgsql-general-ow...@postgresql.org] On Behalf Of Moreno Andreo Sent: 29 July 2016 10:19 To: pgsql-general@postgresql.org Subject: Re: [SPAM] Re: [GENERAL] WAL directory size calculation Il 29/07/2016 10:43, John R Pierce ha

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread FarjadFarid(ChkNet)
@postgresql.org Subject: Re: [SPAM] Re: [GENERAL] WAL directory size calculation Il 29/07/2016 10:43, John R Pierce ha scritto: Aside of this, I'm having 350 DBs that sum up a bit more than 1 TB, and plan to use wal_level=archive because I plan to have a backup server with barman.

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread Moreno Andreo
Il 29/07/2016 10:43, John R Pierce ha scritto: Aside of this, I'm having 350 DBs that sum up a bit more than 1 TB, and plan to use wal_level=archive because I plan to have a backup

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread John R Pierce
Aside of this, I'm having 350 DBs that sum up a bit more than 1 TB, and plan to use wal_level=archive because I plan to have a backup server with barman. With that many databases with that so many objectsand undoubtable client connections, I'd want to spread that across a cluster of smaller

Re: [SPAM] Re: [GENERAL] WAL directory size calculation

2016-07-29 Thread Moreno Andreo
Il 28/07/2016 20:45, Francisco Olarte ha scritto: On Thu, Jul 28, 2016 at 3:25 PM, Moreno Andreo wrote: Obviously ramdisk will be times faster disk, but having a, say, 512 GB ramdisk will be a little too expensive :-) Besides defeating the purpose of WAL, if you are going to use non persistent

Re: [GENERAL] WAL directory size calculation

2016-07-28 Thread Jan Wieck
On Thu, Jul 28, 2016 at 9:54 AM, Andreas Kretschmer wrote: > Without Replication 1 GB would be fine, even with replication. But it must > be realible! > > The required size of WAL depends on what your intended checkpoint_timeout vs. the amount of WAL generated from data turnover is. A rather smal

Re: [GENERAL] WAL directory size calculation

2016-07-28 Thread Francisco Olarte
On Thu, Jul 28, 2016 at 3:25 PM, Moreno Andreo wrote: > Obviously ramdisk will be times faster disk, but having a, say, 512 GB > ramdisk will be a little too expensive :-) Besides defeating the purpose of WAL, if you are going to use non persistent storage for WAL you could as well use minimal le

Re: [GENERAL] WAL directory size calculation

2016-07-28 Thread Moreno Andreo
Il 28/07/2016 15:33, David G. Johnston ha scritto: On Thu, Jul 28, 2016 at 9:25 AM, Moreno Andreo wrote: I've read somewhere that the formula should be 16 MB * 3 *

Re: [GENERAL] WAL directory size calculation

2016-07-28 Thread Moreno Andreo
Il 28/07/2016 15:54, Andreas Kretschmer ha scritto: Am 28.07.2016 um 15:25 schrieb Moreno Andreo: Hi folks! :-) I'm about to bring up my brand new production server and I was wondering if it's possible to calculate (approx.) the WAL directory size. I have to choose what's better in terms of co

Re: [GENERAL] WAL directory size calculation

2016-07-28 Thread Andreas Kretschmer
Am 28.07.2016 um 15:25 schrieb Moreno Andreo: Hi folks! :-) I'm about to bring up my brand new production server and I was wondering if it's possible to calculate (approx.) the WAL directory size. I have to choose what's better in terms of cost vs. performance (we are on Google Cloud Platform)

Re: [GENERAL] WAL directory size calculation

2016-07-28 Thread David G. Johnston
On Thu, Jul 28, 2016 at 9:25 AM, Moreno Andreo wrote: > I've read somewhere that the formula should be 16 MB * 3 * > checkpoint_segment in size. > ​[...]​ > Using the above formula I have: > 16 MB * 3 * 1 GB > that leads to to ... uh .. 48000 TB? > ​You seem to be mis-remembering the formu

[GENERAL] WAL directory size calculation

2016-07-28 Thread Moreno Andreo
Hi folks! :-) I'm about to bring up my brand new production server and I was wondering if it's possible to calculate (approx.) the WAL directory size. I have to choose what's better in terms of cost vs. performance (we are on Google Cloud Platform) between a ramdisk or a separate persistent dis