Tuning Wizard

[Mr Tiger]

Hello. I reinstalled PostgreSQL and Tuning Wizard recently. In the new conf. file i saw: "shared buffers = 1024". The version of Tuning Wizard was not 1.0.0 (i don't remember what exactly (maybe 1.0.2) but it's not important). When I uninstalled Tuning Wizard and installed it again but the version 1.0.0, which I used a week or two ago, I saw in the conf. file "shared buffers = 104521" (as the week ago). And other important values was different.

My questions are:

1) Why the values are different?
2) What do theese values mean? I mean how to compare them to previous values which is measured in megabytes. For example, in the original conf. file: "shared buffers = 32MB". And if we use the "advanced" method of perfomance tuning we have here 1/4 of RAM. In my case it must be "shared buffers = 1024MB" or "shared buffers = 768MB" (I have 4GB of phisical memory, but OS is Windows Vista 32bit).

[APerfect10]

1. I am unsure of the difference. Maybe they are adjusting their formula? With that said, 1024 seems too small for 4GB RAM. 104521 seems more appropriate which I would revert back to.

2. No designation means kilo Bytes and 1024 kB are in 1 MB. Therefore 104521 = 104,521 kB ~= 102 MB.

I already know your next question, why such a large difference between the tuning wizard and the advanced method? The tuning wizard is choosing a "mixed" installation therefore less memory would be used than if it were "dedicated". Furthermore, most PostgreSQL installations are accepting a lot of connections therefore the size cannot be as large. The advanced method will achieve better performance for PokerTracker 3; however, there is also a risk of using too much memory which I have seen cause many issues (hence why I recommend the tuning wizard unless if you know what you are doing).

Best regards,

Derek

[Mr Tiger]

Ok. Thank you for the answer, Derek.

[Mr Tiger]

I reinstalled my Operating System recently and decided to edit postgresql.conf file using recommendations:

http://www.pokertracker.com/forums/view ... 45&t=10393
http://wiki.postgresql.org/wiki/Tuning_ ... SQL_Server

Then I looked through postgresql.conf made by Tuning Wizard (which I used before OS reinstallation) and updated my file a bit. But I haven't understood two parametres:

autovacuum_vacuum_threshold and autovacuum_analyze_threshold

They are set 1000 and 250 by Tuning Wizard. In the original file they are equal to 50. The question: which ones are better: original or Tuning Wizard's?

P.S. PostgreSQL - 8.3.8. PT3 - 29.1beta.

[kraada]

The settings from the tuning wizard should be fine; basically the higher values cause PostgreSQL to wait longer before triggering the autovacuum/autoanalyze. I wouldn't expect that setting to make a huge difference for you either way though.

[Mr Tiger]

The settings from the tuning wizard should be fine; basically the higher values cause PostgreSQL to wait longer before triggering the autovacuum/autoanalyze. I wouldn't expect that setting to make a huge difference for you either way though.

I think so too. Thanks for the answer.

By the way, does no designation mean seconds? (for example, is autovacuum_naptime = 60 equal to autovacuum_naptime = 1min?)

[WhiteRider]

Yes, it is in seconds - see the documentation.