NOTICE: is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum

How long does it take for you in a moderate server with 8GB RAM? We have experience that update takes significantly longer than actual time period, so which creates ever-growing time lag.

asked 20 Sep '10, 10:27

JaakL's gravatar image

accept rate: 0%

edited 20 Sep '10, 13:54

Gnonthgol's gravatar image

Gnonthgol ♦

The wiki page for my SotM performance talk has an SVG image for a 8 GB RAM machine showing that you should be able to process a daily diff in under 10 hours. This is an osm2pgsql import however; in case you are talking about an APIDB import using Osmosis, that is likely to take longer. For osm2pgsql, we have seen that using PostgreSQL 8.4 was much slower than 8.3, so make sure you're not running 8.4. Of course, the usual database tuning tips apply (are your imports perhaps interrupted by an auto-vacuum process? can you afford the risk of having fsync=off? have you increased your shared_buffers from the default?). Sometimes, running an "analyze" command on the database also helps.

permanent link

answered 20 Sep '10, 10:59

Frederik%20Ramm's gravatar image

Frederik Ramm ♦
accept rate: 23%

Thank you! I have actually seen the slides and your presentation, my question was specifically about minutely and hourly diffs. We had hourly diff import test run of 25 hours or so. We use SAS drives in RAID-0, which should give good raw IO speed, and have applied the basic DB optimizations (no vacuum, increased shared_buffers).

(20 Sep '10, 12:50) JaakL

Follow this question

By Email:

Once you sign in you will be able to subscribe for any updates here



Answers and Comments

Markdown Basics

  • *italic* or _italic_
  • **bold** or __bold__
  • link:[text]( "title")
  • image?![alt text](/path/img.jpg "title")
  • numbered list: 1. Foo 2. Bar
  • to add a line break simply add two spaces to where you would like the new line to be.
  • basic HTML tags are also supported

Question tags:


question asked: 20 Sep '10, 10:27

question was seen: 8,843 times

last updated: 20 Sep '10, 13:54

NOTICE: is no longer in use from 1st March 2024. Please use the OpenStreetMap Community Forum