From: Peter Zotov <whitequark@...>
Date: 2012-09-20T13:12:24+09:00
Subject: Re: wow, YAML / Psych in 1.9.3 is *slow*!

Patrick B. писал 19.09.2012 19:14:
> Matt Neuburg wrote in post #1076014:
>> I just started trying Ruby 1.9.3, coming from Ruby 1.8.7, and was
>> surprised to discover YAML's sluggishness. The chief problem seems 
>> to be
>> the Psych library.
>>
> [...]
>> Fortunately, I can switch to the "syck" library:
>>
>> begin
>>   YAML::ENGINE.yamler = 'syck'
>> rescue
>>
>> Using syck, the same routine takes about 7 seconds.
>
> Wow indeed! With a test app with some of my data (having to load 820
> yaml documents) switching to syck took execution from 16.7 to 1.3
> seconds!
> Are there any known side-effects with doing this?

Yes; namely, not being compatible with YAML specification.
Psych was written for a reason, and that reason was Syck's brokenness.
For years it has generated invalid YAML (or was refusing to consume
valid YAML; I have seen different opinions on this) in common cases. 
For
example, this:
http://blog.rubygems.org/2011/08/31/shaving-the-yaml-yak.html

>
> Patrick

-- 
   WBR, Peter Zotov.