Comments on: The sql_logging Debugging Plug-In

By: Steve

Steve — Fri, 12 Sep 2008 21:50:04 +0000

Hi, Rob. Thanks for the heads-up about edge Rails and the patch. I’ll need to verify it still works with older Rails releases, but once that’s done I’ll check in a fix.

By: Rob Anderton

Rob Anderton — Fri, 12 Sep 2008 21:29:45 +0000

Hi,

Firstly, thanks for this really useful plugin, it’s been a big help in identifying potential bottlenecks as we develop our apps.

Unfortunately a recent commit to edge Rails (http://github.com/rails/rails/commit/de0e7507de826bf77fd57cc2a51e27388cb62ff7) has broken the plugin. Quite simple to fix though: the active_record_runtime method no longer takes a parameter, so simply removing it from the redefined method in the plugin fixed it. I’ve pastied a patch here: http://pastie.org/271509 (you’ll have to ignore the whitespace changes!)

Thanks,
Rob

By: Srijith

Srijith — Fri, 13 Jun 2008 10:37:47 +0000

Hi
i am using sql_logging plugin but i am getting error
undefined local variable or method `rows’ for #
what does it mean.Please reply soon.

By: Steve

Steve — Mon, 10 Mar 2008 14:12:10 +0000

AC: I haven’t been able to find a source file called “pg” on my system anywhere and the plug-in appears to load and work fine in the absence of a PostgreSQL gem. I’m wondering if you don’t have an old gem or something lying around that’s causing problems.

I’m happy to continue helping you troubleshoot this, but if you don’t mind, send me an email so the comments here aren’t overwhelmed with our back-and-forth.

By: AC

AC — Sun, 09 Mar 2008 06:02:50 +0000

~ ./script/server -p 4000
=> Booting Mongrel (use ‘script/server webrick’ to force WEBrick)
=> Rails application starting on http://0.0.0.0:4000
=> Call with -d to detach
=> Ctrl-C to shutdown server
** Starting Mongrel listening at 0.0.0.0:4000
** Starting Rails with development environment…
Exiting
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:342:in `new_constants_in’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/rails/activesupport/lib/active_support/core_ext/kernel/requires.rb:7:in `require_library_or_gem’
vendor/rails/activesupport/lib/active_support/core_ext/kernel/reporting.rb:11:in `silence_warnings’
vendor/rails/activesupport/lib/active_support/core_ext/kernel/requires.rb:5:in `require_library_or_gem’
vendor/rails/activerecord/lib/active_record/connection_adapters/postgresql_adapter.rb:4
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:342:in `new_constants_in’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/plugins/sql_logging/lib/sql_logging/postgresql.rb:1
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:342:in `new_constants_in’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/plugins/sql_logging/lib/sql_logging/summary.rb:123
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:342:in `new_constants_in’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/plugins/sql_logging/init.rb:1:in `evaluate_init_rb’
./script/../config/../vendor/rails/railties/lib/rails/plugin.rb:79:in `evaluate_init_rb’
vendor/rails/activesupport/lib/active_support/core_ext/kernel/reporting.rb:11:in `silence_warnings’
./script/../config/../vendor/rails/railties/lib/rails/plugin.rb:75:in `evaluate_init_rb’
./script/../config/../vendor/rails/railties/lib/rails/plugin.rb:39:in `load’
./script/../config/../vendor/rails/railties/lib/rails/plugin/loader.rb:33:in `load_plugins’
./script/../config/../vendor/rails/railties/lib/rails/plugin/loader.rb:32:in `each’
./script/../config/../vendor/rails/railties/lib/rails/plugin/loader.rb:32:in `load_plugins’
vendor/rails/railties/lib/initializer.rb:173:in `load_plugins’
vendor/rails/railties/lib/initializer.rb:89:in `process’
vendor/rails/railties/lib/initializer.rb:49:in `send’
vendor/rails/railties/lib/initializer.rb:49:in `run’
vironment.rb:13
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:342:in `new_constants_in’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/bin/../lib/mongrel/rails.rb:147:in `rails’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/bin/mongrel_rails:113:in `cloaker_’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/lib/mongrel/configurator.rb:149:in `call’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/lib/mongrel/configurator.rb:149:in `listener’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/bin/mongrel_rails:99:in `cloaker_’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/lib/mongrel/configurator.rb:50:in `call’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/lib/mongrel/configurator.rb:50:in `initialize’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/bin/mongrel_rails:84:in `new’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/bin/mongrel_rails:84:in `run’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/lib/mongrel/command.rb:212:in `run’
/Library/Ruby/Gems/1.8/gems/mongrel-1.1.3/bin/mongrel_rails:281
vendor/rails/activesupport/lib/active_support/dependencies.rb:489:in `load’
vendor/rails/activesupport/lib/active_support/dependencies.rb:489:in `load’
vendor/rails/activesupport/lib/active_support/dependencies.rb:342:in `new_constants_in’
vendor/rails/activesupport/lib/active_support/dependencies.rb:489:in `load’
vendor/rails/railties/lib/commands/servers/mongrel.rb:64
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/rails/activesupport/lib/active_support/dependencies.rb:342:in `new_constants_in’
vendor/rails/activesupport/lib/active_support/dependencies.rb:496:in `require’
vendor/rails/railties/lib/commands/server.rb:39
./script/server:4:in `require’
./script/server:4

By: Steve

Steve — Sat, 08 Mar 2008 01:59:31 +0000

AC: Unfortunately, I think the useful information is buried in the “… 34 levels …” part of that backtrace. Mind hacking up your script/server to look like this and sending me the output?

#!/usr/bin/env ruby
begin
require File.dirname(__FILE__) + ‘/../config/boot’
require ‘commands/server’
rescue Exception => e
puts e.backtrace
end

By: AC

AC — Fri, 07 Mar 2008 23:24:52 +0000

I encounter a missing file error when attempting to run my application…

~ piston import http://svn.lightyearsoftware.com/svn/plugins/sql_logging vendor/plugins/sql_logging

Exported r659 from ‘http://svn.lightyearsoftware.com/svn/plugins/sql_logging’ to ‘vendor/plugins/sql_logging’

~ ./script/console

Loading development environment (Rails 2.0.2)
/System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `gem_original_require’: no such file to load — pg (MissingSourceFile)
from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/rubygems/custom_require.rb:27:in `require’
… 34 levels…
from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb/init.rb:251:in `load_modules’
from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb/init.rb:21:in `setup’
from /System/Library/Frameworks/Ruby.framework/Versions/1.8/usr/lib/ruby/1.8/irb.rb:54:in `start’
from /usr/bin/irb:13

By: JM

JM — Wed, 05 Mar 2008 17:31:31 +0000

FYI, I’m having trouble reaching your SVN repository.

By: Steve

Steve — Wed, 05 Mar 2008 14:41:41 +0000

Hi, Andy. While I understand why you’re asking for that, it isn’t very appropriate for anything but the smallest of Rails applications. In order to track what you’re asking for, you’d need to store that kind of information in the database itself so you could collect the data over a variable number of back-end processes and across restarts. Then you’d have to augment the plug-in to not collect data on the SQL that queries/updates the statistics in order to keep things relevant. Finally, you’ll need some kind of cron job that purges old rows so your database does fill up with data about your SQL instead of your application’s data.

This is well beyond the scope of a simple plug-in like sql_logging.

It’s an interesting idea, and something I’ve seen in larger organizations in the past. Who knows, maybe I’ll find a need to do something like this in the future.

By: Andy

Andy — Tue, 04 Mar 2008 08:05:34 +0000

thanks for the great work.

it’d be nice if you keep track of top X queries in every category(most time spent on execution, most bytes returned, etc) in lat X days instead of just per request. Then we just really know which ones need tuning application-wise.