# Activerecord going slow (not in rails...) (VERY slow)

**URL:** <https://www.ruby-forum.com/t/activerecord-going-slow-not-in-rails-very-slow/179037>\
**Category:** Ruby\
**Created:** [November 16, 2009, 9:46am UTC](https://www.ruby-forum.com/t/activerecord-going-slow-not-in-rails-very-slow/179037 "2009-11-16T09:46:03Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![paerez](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/5fc32e/32.png) [@paerez](https://www.ruby-forum.com/u/paerez)\
**Post date:** [November 16, 2009, 9:46am UTC](https://www.ruby-forum.com/t/activerecord-going-slow-not-in-rails-very-slow/179037/1 "2009-11-16T09:46:03Z")

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Active record is taking 7+ seconds to save one item! I’m using  
activerecord not in rails. I have a object that inherits  
ActiveRecord::Base mapped to a table in mysql with 5 string columns and  
3 text columns (and auto-generated id/time columns). One column is a  
serialized hash, but I made it an empty hash in all of the tests I ran.

I have this piece of code:

start = Time.now.to\_i  
entity.save  
puts “Saving one item took #{Time.now.to\_i-start} seconds”

… it outputs

Saving one item took 7 seconds.

The text in one of the text columns is code (quite a bit of C/C++ code),  
and so I thought maybe all that escaping of fancy characters was slowing  
things down. I tried setting each string/text field to a single  
character (“a”,“b”,“c”…) and the saves still took 6-7 seconds.

Doing the same database insertion with:

ActiveRecord::Base.connection.execute

tends to run in \<1 second. Unfortunately this means I have to make sure  
to escape/serialize all my own data, thus rewriting code and potentially  
introducing new bugs. This is not an app that requires speed per-se,  
but it does need to commit about 10,000 of these entries once a week,  
and at 7-8 seconds per that would take 22 hours, which is not  
acceptable.

Does anyone have any ideas why this would be going so insanely slow? I  
am happy to provide further information (platform etc), but since the  
insertions are fast when running ActiveRecord::Base.connection.execute,  
I think this must be something I don’t understand about activerecord  
itself.

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<div class="post-metadata">

**Author:** ![paerez](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/5fc32e/32.png) [@paerez](https://www.ruby-forum.com/u/paerez)\
**Post date:** [November 16, 2009, 11:05am UTC](https://www.ruby-forum.com/t/activerecord-going-slow-not-in-rails-very-slow/179037/2 "2009-11-16T11:05:14Z")

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Nick G. wrote:

> I have this piece of code:
> 
> start = Time.now.to\_i  
> entity.save  
> puts “Saving one item took #{Time.now.to\_i-start} seconds”
> 
> … it outputs
> 
> Saving one item took 7 seconds.

Try saving two entities one after the other, and time each of them.  
Maybe it’s a startup overhead.

Startup problems could be:

- loading in the ActiveRecord and ActiveSupport libraries (although I  
guess in your case they are already loaded)

- slowness establishing a connection to your database, such as lack of  
reverse DNS (e.g. server accepts connection, tries to resolve your IP  
into a name for logging purposes, times out, continues)

If it’s the latter problem, on the server try adding your client’s IP  
address and name into /etc/hosts

> I think this must be something I don’t understand about activerecord  
> itself.

Detailled questions specific to ActiveRecord would be best asked on a  
Rails mailing list, since AR is a component of Rails.

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<div class="post-metadata">

**Author:** ![paerez](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/5fc32e/32.png) [@paerez](https://www.ruby-forum.com/u/paerez)\
**Post date:** [November 16, 2009, 2:06pm UTC](https://www.ruby-forum.com/t/activerecord-going-slow-not-in-rails-very-slow/179037/3 "2009-11-16T14:06:49Z")

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Brian C. wrote:

> Nick G. wrote:
> 
> > I have this piece of code:
> > 
> > start = Time.now.to\_i  
> > entity.save  
> > puts “Saving one item took #{Time.now.to\_i-start} seconds”
> > 
> > … it outputs
> > 
> > Saving one item took 7 seconds.
> 
> Try saving two entities one after the other, and time each of them.  
> Maybe it’s a startup overhead.
> 
> Startup problems could be:
> 
> - loading in the ActiveRecord and ActiveSupport libraries (although I  
> guess in your case they are already loaded)
> 
> - slowness establishing a connection to your database, such as lack of  
> reverse DNS (e.g. server accepts connection, tries to resolve your IP  
> into a name for logging purposes, times out, continues)
> 
> If it’s the latter problem, on the server try adding your client’s IP  
> address and name into /etc/hosts
> 
> > I think this must be something I don’t understand about activerecord  
> > itself.
> 
> Detailled questions specific to ActiveRecord would be best asked on a  
> Rails mailing list, since AR is a component of Rails.

Thanks for the reply 🙂

Unfortunately, in response to your first question:  
–The entries were saved sequentially, time varies slightly (usually 6  
to 9 seconds), but is always extremely high.

And to the second  
– mysql server is localhost, though I don’t know if that precludes it  
from trying to log my IP. However, the fact that calling the  
ActiveRecord::Base.connection.execute command correctly runs so fast  
probably means its not connection issues (I think, I could definitely be  
wrong about that, I have not perused the activerecord code to address  
this specific issue).

As for posting in rails, will do, I think your right. Wasn’t sure where  
to post this one since its not rails, but it is issues with a rails  
library in a plain ruby app.

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<div class="post-metadata">

**Author:** ![paerez](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/5fc32e/32.png) [@paerez](https://www.ruby-forum.com/u/paerez)\
**Post date:** [November 18, 2009, 10:22am UTC](https://www.ruby-forum.com/t/activerecord-going-slow-not-in-rails-very-slow/179037/4 "2009-11-18T10:22:00Z")

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Wojciech P. wrote:

> I recommend to simply profile your code. First extract a very short  
> snippet of code that reproduces the problem. The lesser lines the  
> better. Then run it with ruby-prof. You will clearly see where  
> ActiveRecord::Base#save spends so much time.
> 
> Greetings,  
> Wojtek

ruby-prof is amazing. Thank you for making me aware of its existence,  
how I had never managed to google “ruby profiling” I will never  
understand, but my life is better now.

Unfortunately there was a number of functions slowing things down, the  
solution I ended up using was switching to DataMapper. Its now going  
very fast 🙂

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<div class="post-metadata">

**Author:** ![paerez](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/5fc32e/32.png) [@paerez](https://www.ruby-forum.com/u/paerez)\
**Post date:** [November 17, 2009, 9:31am UTC](https://www.ruby-forum.com/t/activerecord-going-slow-not-in-rails-very-slow/179037/5 "2009-11-17T09:31:13Z")

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I recommend to simply profile your code. First extract a very short  
snippet of code that reproduces the problem. The lesser lines the  
better. Then run it with ruby-prof. You will clearly see where  
ActiveRecord::Base#save spends so much time.

Greetings,  
Wojtek