5 ms·

Speeding up Rails 4.2

197 points by mdasen 12y ago

VeejayRampay 12y ago
Sam Saffron has great write-ups. His article on Ruby 2.1 and garbage collection fine-tuning [1] is a must-read [1] http://samsaffron.com/archive/2014/04/08/ruby-2-1-garbage-collection-ready-for-production http://samsaffron.com/archive/2014/04/08/ruby-2-1-garbage-co...
stanislavb 12y ago
Amazing work! I've bookmarked this post. I think that this approach of profiling Discourse on Rails could be use for any other app/service that is to be migrated to Rails 4.2.
akanet 12y ago
This is exceedingly great work. This is the stuff I love coming to HN for. I had no idea Discourse had a dual-boot mode, much less that it had become a de-facto macro benchmark for both Ruby and Rails. That is awesome.
dynjo 12y ago
You guys might like our latest gem, it outputs ruby-prof as FlameGraphs https://github.com/oozou/ruby-prof-flamegraph https://github.com/oozou/ruby-prof-flamegraph
- jpgvm 12y ago
  Awesome, I love flamegraphs for finding performance bottlenecks.
matthewmacleod 12y ago
This is really great – but I guess I'm a little concerned that large performance regressions aren't being caught at an earlier stage. I wonder if there's scope to automatically keep tabs on Rails Edge performance?
- jpgvm 12y ago
  It would be great if there was a performance benchmark run on CI stack or something and writing output in parseable format so it could be graphed over time etc.
  - gavingmiller 12y ago
    Sam has also blogged about this for Ruby specifically: http://samsaffron.com/archive/2013/12/11/call-to-action-long-running-ruby-benchmark http://samsaffron.com/archive/2013/12/11/call-to-action-long...
patio11 12y ago
Thanks, this is both enormously helpful work for those in the Rails community who depend on the new hotness, and a great writeup for increasing engineering skill levels throughout the community.
mikecmpbll 12y ago
Great write-up, and thanks Sam and Sean! Makes me wonder how bad it would have been without Adequate Record? I would imagine it's a bit disheartening for Aaron that all his hard work making AR 2-times faster have been obliterated by other stuff! ..
- jrochkind1 12y ago
  Makes me wonder if Adequate Record has much impact at all on typical app patterns. Has AdRec been obliterated by other stuff, or is it a microbenchmark that just didn't effect the OP's app much?
  - deleted 12y ago
    [deleted]
grk 12y ago
Ruby 2.2 will add almost-automatic-freezing of string hash keys[1]. I wonder how big of an impact this will have on Rails performance. [1] http://www.sitepoint.com/unraveling-string-key-performance-ruby-2-2/ http://www.sitepoint.com/unraveling-string-key-performance-r...
solutionyogi 12y ago
Sam is a smart guy and an awesome developer. He contributed tons of code for .NET community when he worked at Stack Overflow. I have done a fair amount of performance optimization work in .NET/C#, so I was curious as to what kind of optimizations are involved in Ruby. One of the optimization was this: https://github.com/SamSaffron/rails/commit/9aa2b2d7bf52c0f3974090cd033341be2edeae6d https://github.com/SamSaffron/rails/commit/9aa2b2d7bf52c0f39... Three lessons: 1. Always use profiler to identify code bottlenecks. I don't think I would have ever guessed that the string literal is costing memory allocations causing performance issues. 2. I find it sad that this kind of optimization is required in 2015. In any statically typed language, this would be completely unnecessary. 3. Performance optimization makes code less readable. I think it would make sense to add comment explaining why constant ID was declared. Here's another: https://github.com/SamSaffron/rails/commit/a668b09ee387bf241a3481a764a18a5c8a4df8cd https://github.com/SamSaffron/rails/commit/a668b09ee387bf241... Same story.
- m0th87 12y ago
  String interning has nothing to do with static typing. AFAIK Ruby supports it with symbols and Python with strings in general.
  - riffraff 12y ago
    Recent rubys also supports it for frozen strings (which is the reason it's a frozen string in the commit, probably). The reason it's not done by default is that with mutable strings it would be more complicates/would require a different string implementation, I guess.
Yadi 12y ago
You are the man! Thanks for the great insight on the performance.

197 points by mdasen 12y ago

Sam Saffron has great write-ups. His article on Ruby 2.1 and garbage collection fine-tuning [1] is a must-read [1] http://samsaffron.com/archive/2014/04/08/ruby-2-1-garbage-collection-ready-for-production http://samsaffron.com/archive/2014/04/08/ruby-2-1-garbage-co...

stanislavb 12y ago

Amazing work! I've bookmarked this post. I think that this approach of profiling Discourse on Rails could be use for any other app/service that is to be migrated to Rails 4.2.

akanet 12y ago

This is exceedingly great work. This is the stuff I love coming to HN for. I had no idea Discourse had a dual-boot mode, much less that it had become a de-facto macro benchmark for both Ruby and Rails. That is awesome.

dynjo 12y ago

You guys might like our latest gem, it outputs ruby-prof as FlameGraphs https://github.com/oozou/ruby-prof-flamegraph https://github.com/oozou/ruby-prof-flamegraph

jpgvm 12y ago
Awesome, I love flamegraphs for finding performance bottlenecks.

matthewmacleod 12y ago

This is really great – but I guess I'm a little concerned that large performance regressions aren't being caught at an earlier stage. I wonder if there's scope to automatically keep tabs on Rails Edge performance?

jpgvm 12y ago
It would be great if there was a performance benchmark run on CI stack or something and writing output in parseable format so it could be graphed over time etc.
- gavingmiller 12y ago
  Sam has also blogged about this for Ruby specifically: http://samsaffron.com/archive/2013/12/11/call-to-action-long-running-ruby-benchmark http://samsaffron.com/archive/2013/12/11/call-to-action-long...

patio11 12y ago

Thanks, this is both enormously helpful work for those in the Rails community who depend on the new hotness, and a great writeup for increasing engineering skill levels throughout the community.

mikecmpbll 12y ago

Great write-up, and thanks Sam and Sean! Makes me wonder how bad it would have been without Adequate Record? I would imagine it's a bit disheartening for Aaron that all his hard work making AR 2-times faster have been obliterated by other stuff! ..

jrochkind1 12y ago
Makes me wonder if Adequate Record has much impact at all on typical app patterns. Has AdRec been obliterated by other stuff, or is it a microbenchmark that just didn't effect the OP's app much?
- deleted 12y ago
  [deleted]

grk 12y ago

Ruby 2.2 will add almost-automatic-freezing of string hash keys[1]. I wonder how big of an impact this will have on Rails performance. [1] http://www.sitepoint.com/unraveling-string-key-performance-ruby-2-2/ http://www.sitepoint.com/unraveling-string-key-performance-r...

solutionyogi 12y ago

Sam is a smart guy and an awesome developer. He contributed tons of code for .NET community when he worked at Stack Overflow. I have done a fair amount of performance optimization work in .NET/C#, so I was curious as to what kind of optimizations are involved in Ruby. One of the optimization was this: https://github.com/SamSaffron/rails/commit/9aa2b2d7bf52c0f3974090cd033341be2edeae6d https://github.com/SamSaffron/rails/commit/9aa2b2d7bf52c0f39... Three lessons: 1. Always use profiler to identify code bottlenecks. I don't think I would have ever guessed that the string literal is costing memory allocations causing performance issues. 2. I find it sad that this kind of optimization is required in 2015. In any statically typed language, this would be completely unnecessary. 3. Performance optimization makes code less readable. I think it would make sense to add comment explaining why constant ID was declared. Here's another: https://github.com/SamSaffron/rails/commit/a668b09ee387bf241a3481a764a18a5c8a4df8cd https://github.com/SamSaffron/rails/commit/a668b09ee387bf241... Same story.

m0th87 12y ago
String interning has nothing to do with static typing. AFAIK Ruby supports it with symbols and Python with strings in general.
- riffraff 12y ago
  Recent rubys also supports it for frozen strings (which is the reason it's a frozen string in the commit, probably). The reason it's not done by default is that with mutable strings it would be more complicates/would require a different string implementation, I guess.

Yadi 12y ago

You are the man! Thanks for the great insight on the performance.