Re: Can I have a look at your TuningWizard generated config file?

Hi,
I wanted to start with the TuningWizard and then configure the one they
suggested, thinking that I am starting from good default values.

But I am not able to run TuningWizard for some strange reason, but I am
actually mostly interested in some few settings that it usually provides.
Especially
max_fsm_pages
max_fsm_relations

and also the Vacuum settings, track_activities and such.. I don't know how
to set those things myself but I have figured out some of the other things.

The computer is a Quad Core with 8GB memory and running on Mixed mode on
Ubuntu Server 9.04

I use pg_admin to configure the config file because it provides a good
overview of the things that are set and values.
So this is a special request, if you could provide a screen shot with
perhaps three images, then I could go through it myself one by one and do
similar things on mine.

Thank you and I hope I am not asking to much :)

- Jennifer

Jennifer Trey, 31.07.2009 12:17:
> Hi,
>
> I wanted to start with the TuningWizard and then configure the one they
> suggested, thinking that I am starting from good default values.
>
> But I am not able to run TuningWizard for some strange reason, but I am
> actually mostly interested in some few settings that it usually provides.
> Especially
> max_fsm_pages
> max_fsm_relations
>
Which Postgres version are you using?

IIRC those settings are not longer valid for 8.4

THomas

On Fri, Jul 31, 2009 at 12:29 PM, Thomas Kellerer <spam_eater(at)gmx(dot)net>wrote:

> Jennifer Trey, 31.07.2009 12:17:
>
>> Hi,
>>
>> I wanted to start with the TuningWizard and then configure the one they
>> suggested, thinking that I am starting from good default values.
>>
>> But I am not able to run TuningWizard for some strange reason, but I am
>> actually mostly interested in some few settings that it usually provides.
>> Especially max_fsm_pages
>> max_fsm_relations
>>
>> Which Postgres version are you using?
> IIRC those settings are not longer valid for 8.4
>
> THomas

Aha, ok. I am using 8.4. They are still to be set, confusing.

>
>
>
> --
> Sent via pgsql-general mailing list (pgsql-general(at)postgresql(dot)org)
> To make changes to your subscription:
> http://www.postgresql.org/mailpref/pgsql-general
>

Thanks / Jen

On Fri, Jul 31, 2009 at 12:35, Jennifer Trey<jennifer(dot)trey(at)gmail(dot)com> wrote:
> On Fri, Jul 31, 2009 at 12:29 PM, Thomas Kellerer <spam_eater(at)gmx(dot)net>
> wrote:
>>
>> Jennifer Trey, 31.07.2009 12:17:
>>>
>>> Hi,
>>>
>>> I wanted to start with the TuningWizard and then configure the one they
>>> suggested, thinking that I am starting from good default values.
>>>
>>> But I am not able to run TuningWizard for some strange reason, but I am
>>> actually mostly interested in some few settings that it usually provides.
>>> Especially max_fsm_pages
>>> max_fsm_relations
>>>
>> Which Postgres version are you using?
>> IIRC those settings are not longer valid for 8.4
>>
>> THomas
>
> Aha, ok. I am using 8.4. They are still to be set, confusing.

AFAICS, the edb tuning wizard has not (yet) been updated to support
PostgreSQL 8.4. The hints it gives are for 8.3 and earlier. It would
probably be a good idea if they gave a warning for that, but I take it
they don't :-)

There may be other issues as well, so read up on the documentation for
anything else it recommends to change.

As for these two values, you can just ignore them - they are tuned
dynamically on 8.4.

--
Magnus Hagander
Self: http://www.hagander.net/
Work: http://www.redpill-linpro.com/

Ok. I will.. when it comes to the other settings, like autovacuum and such.
Could I have a look at yours ? :)
I will list the ones that I find important and that i already have figured
out good values for, please fill in if there is more I should look at:

max_connections
effective_cache
random_page_cost
maintenance_work_mem
shared_buffers
work_mem
max_fsm_pages(scratched)
max_fsm_relations(scratched)
wal_buffers

But then there is the log and autovacuum stuff that I have no idea about and
that believe that I could just take from someone else and not really machine
dependant..

Thanks in advance / Jennifer

On Fri, Jul 31, 2009 at 12:48 PM, Magnus Hagander <magnus(at)hagander(dot)net>wrote:

> On Fri, Jul 31, 2009 at 12:35, Jennifer Trey<jennifer(dot)trey(at)gmail(dot)com>
> wrote:
> > On Fri, Jul 31, 2009 at 12:29 PM, Thomas Kellerer <spam_eater(at)gmx(dot)net>
> > wrote:
> >>
> >> Jennifer Trey, 31.07.2009 12:17:
> >>>
> >>> Hi,
> >>>
> >>> I wanted to start with the TuningWizard and then configure the one they
> >>> suggested, thinking that I am starting from good default values.
> >>>
> >>> But I am not able to run TuningWizard for some strange reason, but I am
> >>> actually mostly interested in some few settings that it usually
> provides.
> >>> Especially max_fsm_pages
> >>> max_fsm_relations
> >>>
> >> Which Postgres version are you using?
> >> IIRC those settings are not longer valid for 8.4
> >>
> >> THomas
> >
> > Aha, ok. I am using 8.4. They are still to be set, confusing.
>
> AFAICS, the edb tuning wizard has not (yet) been updated to support
> PostgreSQL 8.4. The hints it gives are for 8.3 and earlier. It would
> probably be a good idea if they gave a warning for that, but I take it
> they don't :-)
>
> There may be other issues as well, so read up on the documentation for
> anything else it recommends to change.
>
> As for these two values, you can just ignore them - they are tuned
> dynamically on 8.4.
>
>
> --
> Magnus Hagander
> Self: http://www.hagander.net/
> Work: http://www.redpill-linpro.com/
>

Is autovacuum on by default?
or do I uncomment

#autovacuum = on

and

#track_counts = on

to enable it? Anything else I should do?

Thanks / Jennifer

On Fri, Jul 31, 2009 at 1:10 PM, Jennifer Trey <jennifer(dot)trey(at)gmail(dot)com>wrote:

> Ok. I will.. when it comes to the other settings, like autovacuum and such.
> Could I have a look at yours ? :)
> I will list the ones that I find important and that i already have figured
> out good values for, please fill in if there is more I should look at:
>
> max_connections
> effective_cache
> random_page_cost
> maintenance_work_mem
> shared_buffers
> work_mem
> max_fsm_pages(scratched)
> max_fsm_relations(scratched)
> wal_buffers
>
> But then there is the log and autovacuum stuff that I have no idea about
> and that believe that I could just take from someone else and not really
> machine dependant..
>
> Thanks in advance / Jennifer
>
>
>
> On Fri, Jul 31, 2009 at 12:48 PM, Magnus Hagander <magnus(at)hagander(dot)net>wrote:
>
>> On Fri, Jul 31, 2009 at 12:35, Jennifer Trey<jennifer(dot)trey(at)gmail(dot)com>
>> wrote:
>> > On Fri, Jul 31, 2009 at 12:29 PM, Thomas Kellerer <spam_eater(at)gmx(dot)net>
>> > wrote:
>> >>
>> >> Jennifer Trey, 31.07.2009 12:17:
>> >>>
>> >>> Hi,
>> >>>
>> >>> I wanted to start with the TuningWizard and then configure the one
>> they
>> >>> suggested, thinking that I am starting from good default values.
>> >>>
>> >>> But I am not able to run TuningWizard for some strange reason, but I
>> am
>> >>> actually mostly interested in some few settings that it usually
>> provides.
>> >>> Especially max_fsm_pages
>> >>> max_fsm_relations
>> >>>
>> >> Which Postgres version are you using?
>> >> IIRC those settings are not longer valid for 8.4
>> >>
>> >> THomas
>> >
>> > Aha, ok. I am using 8.4. They are still to be set, confusing.
>>
>> AFAICS, the edb tuning wizard has not (yet) been updated to support
>> PostgreSQL 8.4. The hints it gives are for 8.3 and earlier. It would
>> probably be a good idea if they gave a warning for that, but I take it
>> they don't :-)
>>
>> There may be other issues as well, so read up on the documentation for
>> anything else it recommends to change.
>>
>> As for these two values, you can just ignore them - they are tuned
>> dynamically on 8.4.
>>
>>
>> --
>> Magnus Hagander
>> Self: http://www.hagander.net/
>> Work: http://www.redpill-linpro.com/
>>
>
>

On Friday 31 July 2009 6:18:30 am Jennifer Trey wrote:
> Is autovacuum on by default?
> or do I uncomment
>
> #autovacuum = on
>
> and
>
> #track_counts = on
>
> to enable it? Anything else I should do?
>
> Thanks / Jennifer

You might check out this part of the manual :)
http://www.postgresql.org/docs/8.4/interactive/runtime-config-autovacuum.html

--
Adrian Klaver
aklaver(at)comcast(dot)net

Hi Jennifer,

Magnus Hagander wrote:
> On Fri, Jul 31, 2009 at 12:35, Jennifer Trey<jennifer(dot)trey(at)gmail(dot)com> wrote:
>> On Fri, Jul 31, 2009 at 12:29 PM, Thomas Kellerer <spam_eater(at)gmx(dot)net>
>> wrote:
>>> Jennifer Trey, 31.07.2009 12:17:
>>>> Hi,
>>>>
>>>> I wanted to start with the TuningWizard and then configure the one they
>>>> suggested, thinking that I am starting from good default values.
>>>>
>>>> But I am not able to run TuningWizard for some strange reason, but I am
>>>> actually mostly interested in some few settings that it usually provides.
>>>> Especially max_fsm_pages
>>>> max_fsm_relations
>>> Which Postgres version are you using?
>>> IIRC those settings are not longer valid for 8.4
>>>
>>> THomas
>> Aha, ok. I am using 8.4. They are still to be set, confusing.
> AFAICS, the edb tuning wizard has not (yet) been updated to support
> PostgreSQL 8.4. The hints it gives are for 8.3 and earlier. It would
> probably be a good idea if they gave a warning for that, but I take it
> they don't :-)
TuningWizard (latest version 1.3) has been updated to support PostgreSQL
8.4.
> As for these two values, you can just ignore them - they are tuned
> dynamically on 8.4.
Agree.
It will be taken care automatically on 8.4.

--
Thanks & Regards,
Ashesh Vashi

EnterpriseDB INDIA: http://www.enterprisedb.com

On Fri, Jul 31, 2009 at 15:47, Ashesh
Vashi<ashesh(dot)vashi(at)enterprisedb(dot)com> wrote:
> Magnus Hagander wrote:
> AFAICS, the edb tuning wizard has not (yet) been updated to support
> PostgreSQL 8.4. The hints it gives are for 8.3 and earlier. It would
> probably be a good idea if they gave a warning for that, but I take it
> they don't :-)
>
> TuningWizard (latest version 1.3) has been updated to support PostgreSQL
> 8.4.

Your download page only lists 1.1 as download :-) Glad to hear an
updated version exists, I assume it'll make it there eventually?

--
Magnus Hagander
Self: http://www.hagander.net/
Work: http://www.redpill-linpro.com/

Hi Magnus,

Magnus Hagander wrote:
> On Fri, Jul 31, 2009 at 15:47, Ashesh
> Vashi<ashesh(dot)vashi(at)enterprisedb(dot)com> wrote:
>> Magnus Hagander wrote:
>> AFAICS, the edb tuning wizard has not (yet) been updated to support
>> PostgreSQL 8.4. The hints it gives are for 8.3 and earlier. It would
>> probably be a good idea if they gave a warning for that, but I take it
>> they don't :-)
>>
>> TuningWizard (latest version 1.3) has been updated to support PostgreSQL
>> 8.4.
> Your download page only lists 1.1 as download :-) Glad to hear an
> updated version exists, I assume it'll make it there eventually?
Right now, the latest version is available only through the stack-builder.
It will be available soon on download pages too. :)

--
Thanks & Regards,
Ashesh Vashi

EnterpriseDB INDIA: http://www.enterprisedb.com

I think I got everything now. Most things where on by default it seems.

#------------------------------------------------------------------------------
# RUNTIME STATISTICS
#------------------------------------------------------------------------------

# - Query/Index Statistics Collector -

track_activities = off *#I turned this off
*#track_counts = on
#track_functions = none # none, pl, all
track_activity_query_size = 16kB
#update_process_title = on
#stats_temp_directory = 'pg_stat_tmp'

# - Statistics Monitoring -

#log_parser_stats = off
#log_planner_stats = off
#log_executor_stats = off
#log_statement_stats = off

#------------------------------------------------------------------------------
# AUTOVACUUM PARAMETERS
#------------------------------------------------------------------------------

#autovacuum = on # Enable autovacuum subprocess? 'on'
# requires track_counts to also be on.
#log_autovacuum_min_duration = -1 # -1 disables, 0 logs all actions and
# their durations, > 0 logs only
# actions running at least this number
# of milliseconds.
#autovacuum_max_workers = 3 # max number of autovacuum subprocesses
*autovacuum_naptime* = 20min # time between autovacuum runs
*autovacuum_vacuum_threshold* = 250 # min number of row updates before
# vacuum
*autovacuum_analyze_threshold* = 125 # min number of row updates before
# analyze
#autovacuum_vacuum_scale_factor = 0.2 # fraction of table size before
vacuum
#autovacuum_analyze_scale_factor = 0.1 # fraction of table size before
analyze
#autovacuum_freeze_max_age = 200000000 # maximum XID age before forced
vacuum
# (change requires restart)
#autovacuum_vacuum_cost_delay = 20ms # default vacuum cost delay for
# autovacuum, in milliseconds;
# -1 means use vacuum_cost_delay
#autovacuum_vacuum_cost_limit = -1 # default vacuum cost limit for
# autovacuum, -1 means use
# vacuum_cost_limit

I am not going for the TuningWizard anymore since I set everything up
manually that I believe it normally touches.

Thanks all (on the other threads as well :) ), you have been extremely
helpful. I must say that I love this mailing list. And PostgreSQL :)

Sincerely / Jennifer

Jennifer Trey escribió:
> I think I got everything now. Most things where on by default it seems.
>
>
> #------------------------------------------------------------------------------
> # RUNTIME STATISTICS
> #------------------------------------------------------------------------------
>
> # - Query/Index Statistics Collector -
>
> track_activities = off *#I turned this off

What for?

> #autovacuum_vacuum_scale_factor = 0.2 # fraction of table size before
> vacuum
> #autovacuum_analyze_scale_factor = 0.1 # fraction of table size before
> analyze

Hmm, does the tuning wizard not touch these?

--
Alvaro Herrera http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.

On Fri, 31 Jul 2009, Jennifer Trey wrote:

> So this is a special request, if you could provide a screen shot with
> perhaps three images, then I could go through it myself one by one and
> do similar things on mine.

As a general note here, the Enterprise DB TuningWizard program is
technically open-source, but the actual tuning it does runs as a private
web service. They apparently want to keep its implementation details to
themselves and are just providing this as a helpful service to people.

As such, I know I really don't want to see any such output show up on one
of these mailing lists. The PostgreSQL community at large should avoid
learning what they're doing just so it's clear that any open development
work here isn't taking their ideas. I hope no one actually shows the
output from the program downthread, once I read this message I deleted
everything else in it so at least I stay clean.

The TuningWizard software redirects you over to
http://forums.enterprisedb.com for support with it and that's really the
right place to ask questions about that specific program.

--
* Greg Smith gsmith(at)gregsmith(dot)com http://www.gregsmith.com Baltimore, MD

Hi Greg!

On Fri, Jul 31, 2009 at 11:43 AM, Greg Smith<gsmith(at)gregsmith(dot)com> wrote:

> As such, I know I really don't want to see any such output show up on one of
> these mailing lists.  The PostgreSQL community at large should avoid
> learning what they're doing just so it's clear that any open development
> work here isn't taking their ideas.  I hope no one actually shows the output
> from the program downthread, once I read this message I deleted everything
> else in it so at least I stay clean.

What exactly is the concern? I'm for healthy paranoia, but I'd like to
know what exactly you're paranoid about.

I'd rather resolve whatever is bothering you by being direct and
talking to EDB (if whatever this is can be changed), than to have you
desperately deleting threads.

-selena

--
http://chesnok.com/daily - me
http://endpoint.com - work

On Fri, 31 Jul 2009, Selena Deckelmann wrote:

> What exactly is the concern? I'm for healthy paranoia, but I'd like to
> know what exactly you're paranoid about.

EDB has this program that runs as a web service. It runs a proprietary
tuning routine (what they call "DynaTune") and gives the results out to
people, which is a nice service they're providing. No problem with that
and I'm glad they help out by providing it.

But I don't want to see those results showing up here, for fear that
community efforts to provide a similar service would be comprimised by
seeing it. You'll see people here warning against discussing the design
of proprietary bits of O****e's implementation lest it similarly taint the
PostgreSQL design. I'm just pointing out that the output of EDB's Tuning
Wizard could be a similarly protected bit of intellectual property.

I already asked EDB last year whether they were intending to release the
DynaTune program and didn't get the impression that was forthcoming, and
it's unreasonable to ask them to, so I don't know what further questions
you might ask them.

--
* Greg Smith gsmith(at)gregsmith(dot)com http://www.gregsmith.com Baltimore, MD

Hmm.. not done quite yet it seems :(

I tried initially to set shared_buffers to 1024MB but I got this message :

2009-08-01 15:04:46 CESTFATAL: could not create shared memory segment:
Invalid argument
2009-08-01 15:04:46 CESTDETAIL: Failed system call was shmget(key=5432001,
size=1106247680, 03600).
2009-08-01 15:04:46 CESTHINT: This error usually means that PostgreSQL's
request for a shared memory segment exceeded your kernel's SHMMAX parameter.
You can either reduce the request size or reconfigure the kernel with
larger SHMMAX. To reduce the request size (currently 1106247680 bytes),
reduce PostgreSQL's shared_buffers parameter (currently 131072) and/or its
max_connections parameter (currently 153).
If the request size is already small, it's possible that it is less
than your kernel's SHMMIN parameter, in which case raising the request size
or reconfiguring SHMMIN is called for.

Lowered it to 64MB and same thing happen. Changed to 128kB and the server
started.

Reading on shared_buffers thing on
http://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server
<http://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server>I
can see that this seems to be something expected, but I am confused on how
to fix this ...

sysctl -a | grep -i shm
error: permission denied on key 'net.ipv4.route.flush'
error: permission denied on key 'net.ipv6.route.flush'
kernel.shmmax = 33554432
kernel.shmall = 2097152
kernel.shmmni = 4096
vm.hugetlb_shm_group = 0

I am running Ubuntu Server 9.04 so I am guessing I should be looking under
Linux on
http://www.postgresql.org/docs/current/static/kernel-resources.html

I am confused about this part :

$ sysctl -w kernel.shmmax=134217728$ sysctl -w kernel.shmall=2097152

In addition these settings can be saved between reboots in /etc/sysctl.conf.

Should I just append that file with two lines :

kernel.shmmax=10486808576

kernel.shmmall=?? What should be here? Leave it alone? I am thinking I
shouldn't include this, only the above one... right?

Thanks in advance / Jen

cat /proc/sys/kernel/shmmax

1999999999

shmmax controls the maximum amount of memory to be allocated
for shared memory,

(1,999,999,999 in this instance.)

http://ps-ax.com/shared-mem.html

concerning shmall
set shmall parameter for total amount of shared memory pages that can be used system wide

shmall could be ceil(shmmax/PAGE_SIZE)
http://www.puschitz.com/TuningLinuxForOracle.shtml#SettingSharedMemory

PAGE_SIZE determined by
$ getconf PAGE_SIZE
4096

Martin Gainty
______________________________________________
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Date: Sat, 1 Aug 2009 15:48:34 +0200
Subject: Re: [GENERAL] Can I have a look at your TuningWizard generated config file?
From: jennifer(dot)trey(at)gmail(dot)com
To: gsmith(at)gregsmith(dot)com
CC: selenamarie(at)gmail(dot)com; pgsql-general(at)postgresql(dot)org

Hmm.. not done quite yet it seems :(
I tried initially to set shared_buffers to 1024MB but I got this message :

2009-08-01 15:04:46 CESTFATAL: could not create shared memory segment: Invalid argument
2009-08-01 15:04:46 CESTDETAIL: Failed system call was shmget(key=5432001, size=1106247680, 03600).2009-08-01 15:04:46 CESTHINT: This error usually means that PostgreSQL's request for a shared memory segment exceeded your kernel's SHMMAX parameter. You can either reduce the request size or reconfigure the kernel with larger SHMMAX. To reduce the request size (currently 1106247680 bytes), reduce PostgreSQL's shared_buffers parameter (currently 131072) and/or its max_connections parameter (currently 153).
If the request size is already small, it's possible that it is less than your kernel's SHMMIN parameter, in which case raising the request size or reconfiguring SHMMIN is called for.

Lowered it to 64MB and same thing happen. Changed to 128kB and the server started.
Reading on shared_buffers thing on http://wiki.postgresql.org/wiki/Tuning_Your_PostgreSQL_Server I can see that this seems to be something expected, but I am confused on how to fix this ...

sysctl -a | grep -i shm
error: permission denied on key 'net.ipv4.route.flush'error: permission denied on key 'net.ipv6.route.flush'kernel.shmmax = 33554432
kernel.shmall = 2097152kernel.shmmni = 4096vm.hugetlb_shm_group = 0
I am running Ubuntu Server 9.04 so I am guessing I should be looking under Linux on http://www.postgresql.org/docs/current/static/kernel-resources.html

I am confused about this part : $ sysctl -w kernel.shmmax=134217728
$ sysctl -w kernel.shmall=2097152
In addition these settings can be saved between reboots in /etc/sysctl.conf.
Should I just append that file with two lines :
kernel.shmmax=10486808576kernel.shmmall=?? What should be here? Leave it alone? I am thinking I shouldn't include this, only the above one... right?

Thanks in advance / Jen

_________________________________________________________________
Get free photo software from Windows Live
http://www.windowslive.com/online/photos?ocid=PID23393::T:WLMTAGL:ON:WL:en-US:SI_PH_software:082009

For 1024MB = 1024*1024*1024 bytes
kernel.shmmax=1073741824

and for ceil(1073741824)/4096) = 262144 which is actually much smaller than
the setting that is the default ( 2097152 )

But setting these two to the values above still gives similar error and the
pg-server still doesn't start.

2009-08-01 17:58:19 CESTFATAL: could not create shared memory segment:
Invalid argument 2009-08-01 17:58:19 CESTDETAIL: Failed system call was
shmget(key=5432001, size=1106247680, 03600). 2009-08-01 17:58:19 CESTHINT:
This error usually means that PostgreSQL's request for a shared memory
segment exceeded your kernel's SHMMAX parameter. You can either reduce the
request size or reconfigure the kernel with larger SHMMAX. To reduce the
request size (currently 1106247680 bytes), reduce PostgreSQL's
shared_buffers parameter (currently 131072) and/or its max_connections
parameter (currently 153). If the request size is already small, it's
possible that it is less than your kernel's SHMMIN parameter, in which case
raising the request size or reconfiguring SHMMIN is called for. The
PostgreSQL documentation contains more information about shared memory
configuration.

Increasing to

kernel.shmmax=1106247680 kernel.shmall=29250

doesn't seem to help either :

2009-08-01 18:09:55 CESTFATAL: could not create shared memory segment: No
space left on device 2009-08-01 18:09:55 CESTDETAIL: Failed system call was
shmget(key=5432001, size=1106247680, 03600). 2009-08-01 18:09:55 CESTHINT:
This error does *not* mean that you have run out of disk space. It occurs
either if all available shared memory IDs have been taken, in which case you
need to raise the SHMMNI parameter in your kernel, or because the system's
overall limit for shared memory has been reached. If you cannot increase the
shared memory limit, reduce PostgreSQL's shared memory request (currently
1106247680 bytes), by reducing its shared_buffers parameter (currently
131072) and/or its max_connections parameter (currently 153). The PostgreSQL
documentation contains more information about shared memory configuration.

but this does work :

kernel.shmmax=1106247680
kernel.shmall=2097152 (default value)

So I am guessing some manuals needs an update :P

/Jennifer