Pankaj Kumar's Weblog

Hi,

there are many solutions in the Java world that are getting close to RoR's touted development productivity. I suggest you take a look at RIFE, and our persistence engine. There are many similarities, except that we don't base it on the Active Record pattern and don't magically create classes from database schemas.

If you want the scaffolding features of RoR, we release RIFE/Crud a week ago and it received a lot of very positive responses. Many people are already successfully adopting it.

As far as scripting languages is concerned, take a look at Groovy. It has matured a lot and the performance is excellent (I have trouble distinguishing any difference with regular Java code).

About the memory usage, Java tends to cache a lot if the memory is available. When you reduce the allowed heap usage, you'll usually see that everything just continues to run without any problems.

Good luck!

Geert

now ruby fevered guys will present you C code called from ruby to cover this issue ;).
The problem with the web applications, i think is more related with external applications issues. Database access and more importantly server issues. Also java frameworks tends to use too much abstraction in cases.
But at the end, using ruby is not really logical for many type of applications (including web applications) when you put a bit of complex business logic (lets say graphics generation, mathematical operations, text processing, pdf generation etc) on the server side ruby's performance degrades horribly and you need to go C hacking..
On the other hand, Java's tool support is providing enough productivity witohut compromising from performance.

Interesting post.
I would suggest to post your code to a Ruby forum or mailing list for improvement. Maybe they would have some suggestions to make it faster. Taht's said, I have no doubt that Java is faster. But since you're new to Ruby, that would be fair to get some feedback. I don't Ruby myself.

Hi,

I'm a Ruby developer and your code is so slow mostly because of the call to DateTime.strptime in the LogEntry contructor. This method is written in pure Ruby and quite complicated. Based on how you use the LogEntry class in webstat.rb, it is probably not necessary to parse every date on every line of your log file. Not parsing every date should make the code more than 3 times faster, based on some simple benchmarking I have done. I also suspect your regular expressions could use some tweaking.

Despite that, there is no doubt Java is faster than Ruby. In fact other scripting languages like Perl and Python are also faster. Most of this is due to the fact that Ruby does not in fact have a VM, as Mr. Kumar suggests. It actually evaluates an AST (Abstract Syntax Tree, the result of parsing) directly. There is currently work being done to create a VM for Ruby, called YARV. This will make Ruby much faster.

Still even when Ruby gets a VM Java will probably always be faster, for a few reasons:

1. Java is a statically typed language, which allows for many more optimizations that are harder or impossible in a dynamically typed language like Ruby. Things likes Ruby's eval() method and the fact that classes can be reopened and modified makes things harder to optimize as well.
2. Java has many man-years and millions of dollars invested in making it fast. Ruby does not have a huge corporation with thousands of programmers behind it. Despite that Ruby does pretty darn good, and in fact Ruby is probably faster than Java was back in the early days.

Also when it comes to web development, runtime performance of the language itself has less of an impact, as network latency and in particular, database access, are usually the bottlenecks.

Still, let's not become language zealots. I really enjoy programming in Ruby, but I still do Java in my day job, and they are both good languages. Java performs faster, but I feel Ruby is easier and more enjoyable to program in. Others may feel differently and that is fine. To each their own.

Hi,

i've tried your ruby program on a 150Mbyte log file and it takes 13.6 Minutes (P4 2.8 Ghz, ruby 1.8.3). With the rewriten LogEntry class below it takes only 3 minutes.

require 'date'

class LogEntry
attr_reader :host, :user, :auth, :date, :referrer, :ua, :rcode, :nbytes, :url

@@epat = Regexp.new('^(\S+) (\S+) (\S+) \[(\d+)\/(\S+)\/(\d+):(\d+):(\d+):(\d+) (.+)\] "(.+)" (\d+) (\d+) "(.+)" "(.+)"')
@@rpat = Regexp.new('^(\S+) (.+) (.+)$')

def initialize(line)
md = @@epat.match(line)
@host = md[1]
@user = md[2]
@auth = md[3]
@day = md[4]
@month = md[5]
@year = md[6]
@hour = md[7]
@minute = md[8]
@sec = md[9]
@diff = md[10]
@request = md[11]
@rcode = md[12]
bs = md[13]
@nbytes = (bs == "-" ? 0 : Integer(bs))
@referrer = md[14]
@ua = md[15]

md = @@rpat.match(@request)
@method = md[1]
@url = md[2]
@proto = md[3]
@date = @day.to_s() + "/" + Date::ABBR_MONTHNAMES.index(@month).to_s() + "/"+@year.to_s() +":"+@hour.to_s()+":"+@minute.to_s()+":"+@sec.to_s()

end
def to_s()
"LogEntry[host:" + @host + ", date:" + @date + ", referrer:" + @referrer + ", url:" + @url + ", ua:" + @ua + ", user:" + @user + ", auth:" + @auth + ", rcode:" + @rcode.to_s + ", nbytes:" + @nbytes.to_s + "]";
end
end

I think it is not fair to blame a language for all performance issues and it is not fair to compare only the runtime of ruby vs. java.

Regards,
Roland

Thankyou note From Pankaj: Thanks. Really appreciate you trying out the code and sharing the improvements.

Also for comparison with JDK -client and JDK -server -Xint see

GP4 Computer Language Shootout Benchmarks

You are doing an insane amount of extra writing

hows about:

require 'date'

class LogEntry
attr_reader :host, :user, :auth, :date, :referrer, :ua, :rcode, :nbytes, :url

@@epat = Regexp.new('^(\S+) (\S+) (\S+) \[(\d+)\/(\S+)\/(\d+):(\d+):(\d+):(\d+) (.+)\] "(.+)" (\d+) (\d+) "(.+)" "(.+)"')
@@rpat = Regexp.new('^(\S+) (.+) (.+)$')

def convertBS( bs )
case bs
when "-":
0
else
Integer( bs )
end
end

def initialize(line)

( fullMatch_ignored, @host, @user, @auth, @day, @month, @year, @hour, @minute, @sec, @diff, @request, @rcode, bs, @referrer, @ua ) = @@epat.match line
@nbytes = convertBS bs

( fullMatch_ignored, @method, @url, @proto ) = @@rpat.match @request
@date = @day.to_s() + "/" + Date::ABBR_MONTHNAMES.index(@month).to_s() + "/"+@year.to_s() +":"+@hour.to_s()+":"+@minute.to_s()+":"+@sec.to_s()

end
def to_s()
"LogEntry[host:" + @host + ", date:" + @date + ", referrer:" + @referrer + ", url:" + @url + ", ua:" + @ua + ", user:" + @user + ", auth:" + @auth + ", rcode:" + @rcode.to_s + ", nbytes:" + @nbytes.to_s + "]";
end
end

Just seems cleaner, but I do know this is just the symantic issue.