Forum OpenACS Development: Re: Slow queries on Bug-Tracker. Some SQL Tunning

2: Re: Slow queries on Bug-Tracker. Some SQL Tunning (response to 1)

Posted by Dave Bauer on 03/15/10 02:33 PM

I think you might need to tune your database.

Or maybe the query only is slow with the large amount of data you have.

How many shared buffers do you have? Also make sure in generaly your server has enough RAM for the operating system to cache the disk reads (on Linux anyway, I am not sure how it works on other platforms).

Genreally around 128mb shared buffers seems to help in many cases, I haven't found a site that needed more, but your results may vary. I would experiment but increasing shared buffers to at least 128mb if is not already.

3: Re: Slow queries on Bug-Tracker. Some SQL Tunning (response to 2)

Posted by Eduardo Santos on 03/15/10 02:52 PM

Hi Dave,

I don't think I can improve this by tuning. I've already played with the indexes, changed the shared buffers, etc. I've got to the amount of 3GB for shared buffers, wich is close to the best results I've got grom pgbench. The machine is a dedicated IBM Server with 16GB RAM and two Quad Cores (Linux sees it as 8 processors). If there's any way to improve this query with server tuning, it's beyond my knowledge to do it.

That's why I've thought about tuning the query, wich seems to be a complex task. Do you think there's any way it cab be tuned? I couldn't find any looking at the data model.