Hi,
I am doing some text processing.
I clean every variable after each loop and use the
GC.start
ObjectSpace.garbage_collect
after each loop too.
So I have three variables whose cumulative size always remain inferior
to 100'000 utf8 characters.
Nevertheless my free RAM is falling with run-time length like if each
time loaded is added to the RAM.
How can I force the RAM to clean completely from no-used stuff?
thanks
--
Posted via http://www.ruby-forum.com/.
Without seeing code it's hard to comment, but two things which spring instantly to mind:
1. are you sure your input data is no longer being referenced elsewhere in the program as live objects are not garbage collected;
2. are you generating symbols as part of processing the input data as these are not garbage collected (at least not in Ruby 1.8).
Also in general if you have enough memory, don't force garbage collection: the Ruby runtime does this perfectly well and the overall performance of your program will improve. 300k of utf8 is such a trivial amount of memory consumption...
Ellie
Eleanor McHugh
Games With Brains
http://slides.games-with-brains.net
On 17 Mar 2009, at 12:10, Edouard Dantes wrote:
Hi,
I am doing some text processing.
I clean every variable after each loop and use the
GC.start
ObjectSpace.garbage_collect
after each loop too.So I have three variables whose cumulative size always remain inferior
to 100'000 utf8 characters.Nevertheless my free RAM is falling with run-time length like if each
time loaded is added to the RAM.How can I force the RAM to clean completely from no-used stuff?
----
raise ArgumentError unless @reality.responds_to? :reason
Without seeing code it's hard to comment,
Thanks for answer,
well, the loops are too basic to create problems, it's fill array with
values & write to file.
RAM jumps are too erratic (5 or 10% for 2GB RAM)
The only processor angry stuff (and possibly RAM too) is the following
parsing line, imported from another file.
Nokogiri::HTML(page).css('div a').map{|dts|
dts.text.gsub(/\s+/,"").gsub(/[^A-Za-z0-9\s]/,'Z') }
This line runs thousands of time, might the implied regex feed RAM with
datas without cleaning?
thanks
--
Posted via http://www.ruby-forum.com/\.
Edouard Dantes wrote:
RAM jumps are too erratic (5 or 10% for 2GB RAM)
Note that this RAM load 'noise' leads to an increasing average RAM load.
--
Posted via http://www.ruby-forum.com/\.
I'm not sure it'll make much difference but moving the regex creation into the enclosing scope seems neater:
spaces = /\s+/
chars = /[^A-Za-z0-9\s]/
Nokogiri::HTML(page).css('div a').map { |dts|
dts.text.gsub(spaces, "").gsub(chars, 'Z')
}
Likewise changing the logic to use gsub! will reduce the number of transient string objects being created and that will reduce memory usage.
I'd also be interested to see the code you're using for writing to file as the nature of the RAM usage jumps suggests you could be experiencing a buffering artefact.
Ellie
Eleanor McHugh
Games With Brains
http://slides.games-with-brains.net
On 17 Mar 2009, at 15:23, Edouard Dantes wrote:
Without seeing code it's hard to comment,
Thanks for answer,
well, the loops are too basic to create problems, it's fill array with
values & write to file.RAM jumps are too erratic (5 or 10% for 2GB RAM)
The only processor angry stuff (and possibly RAM too) is the following
parsing line, imported from another file.Nokogiri::HTML(page).css('div a').map{|dts|
dts.text.gsub(/\s+/,"").gsub(/[^A-Za-z0-9\s]/,'Z') }This line runs thousands of time, might the implied regex feed RAM with
datas without cleaning?
----
raise ArgumentError unless @reality.responds_to? :reason
Use /o (once) flag for regexen (gsub(/\s+/o,"")), or make them
constants out of the loop - you'll save two object creations for each
loop.
Try replacing the block body with
tmp = dts.text.gsub(/\s+/,"") # creates a copy of the string, with
whitespace removed
tmp.gsub!(/[^A-Za-z0-9\s]/,'Z') # avoid creating another copy of the string
tmp # return the temporary string
Run your code under RubyMemoryValidator, or at least under ruby-prof
(or any other similar tool) to see what kind of objects get created
and where. If you post the code and some sample data, I might find
some time to run with MemoryValidator for you.
Jano
On Tue, Mar 17, 2009 at 16:23, Edouard Dantes <edrd.dantes@gmail.com> wrote:
Without seeing code it's hard to comment,
Thanks for answer,
well, the loops are too basic to create problems, it's fill array with
values & write to file.RAM jumps are too erratic (5 or 10% for 2GB RAM)
The only processor angry stuff (and possibly RAM too) is the following
parsing line, imported from another file.Nokogiri::HTML(page).css('div a').map{|dts|
dts.text.gsub(/\s+/,"").gsub(/[^A-Za-z0-9\s]/,'Z') }
Hi.
thanks for your help,
actually after running one unit at a time it appears the problem comes
from :
Nokogiri::HTML(page)
if i supress everything else but keep it looping with a "while true" my
RAM gets eaten out.
I am giving a try to hpricot & let you know if it solves the problem
NOTE: I run it on openSuse 11.1 x86-64 & ruby 1.8.6 with the current gem
--remote nokogiri.
--
Posted via http://www.ruby-forum.com/.
well, the loops are too basic to create problems, it's fill array with
values & write to file.RAM jumps are too erratic (5 or 10% for 2GB RAM)
The only processor angry stuff (and possibly RAM too) is the following
parsing line, imported from another file.Nokogiri::HTML(page).css('div a').map{|dts|
dts.text.gsub(/\s+/,"").gsub(/[^A-Za-z0-9\s]/,'Z') }This line runs thousands of time, might the implied regex feed RAM with
datas without cleaning?I'm not sure it'll make much difference but moving the regex creation into
the enclosing scope seems neater:spaces = /\\s\+/ chars = /\[^A\-Za\-z0\-9\\s\]/
This is generally less efficient and AFAIK there are no memory leaks
attached to this. It's a different story with varying regular
expressions (i.e. based on input or configuration). But in this case
I'd leave them in place.
Nokogiri::HTML\(page\)\.css\('div a'\)\.map \{ |dts| dts\.text\.gsub\(spaces, ""\)\.gsub\(chars, 'Z'\) \}Likewise changing the logic to use gsub! will reduce the number of transient
string objects being created and that will reduce memory usage.
True, maybe the first gsub needs to stay in order to avoid aliasing effects.
I'd also be interested to see the code you're using for writing to file as
the nature of the RAM usage jumps suggests you could be experiencing a
buffering artefact.
There was also an issue in 1.8.* related to Array#shift or #unshift.
And I agree with your general statement to not explicitly force GC.
Rather look for memory leaks. Edouard, you might get a first idea
where you spend your memory by dumping instance counts in intervals
(sample attached).
Kind regards
robert
mem-stat.rb (839 Bytes)
2009/3/17 Eleanor McHugh <eleanor@games-with-brains.com>:
On 17 Mar 2009, at 15:23, Edouard Dantes wrote:
--
remember.guy do |as, often| as.you_can - without end
Interesting, I'll have to do some tests to see what the difference is in practice as this is a code pattern I use a lot.
Ellie
Eleanor McHugh
Games With Brains
http://slides.games-with-brains.net
On 18 Mar 2009, at 16:25, Robert Klemme wrote:
2009/3/17 Eleanor McHugh <eleanor@games-with-brains.com>:
spaces = /\s+/
chars = /[^A-Za-z0-9\s]/This is generally less efficient and AFAIK there are no memory leaks
attached to this. It's a different story with varying regular
expressions (i.e. based on input or configuration). But in this case
I'd leave them in place.
----
raise ArgumentError unless @reality.responds_to? :reason
It seems, the difference has decreased with 1.9, but you can at least say that it's not slower to have a regular expression inline:
allruby rx.rb
ruby 1.8.5 (2006-08-25) [i386-linux]
Rehearsal -------------------------------------------------------
inline 15.300000 4.000000 19.300000 ( 19.354039)
separate 15.440000 3.940000 19.380000 ( 19.426682)
out of the loop 15.370000 4.000000 19.370000 ( 19.423543)
--------------------------------------------- total: 58.050000sec
user system total real
inline 15.330000 3.990000 19.320000 ( 19.341197)
separate 15.400000 3.980000 19.380000 ( 19.426264)
out of the loop 15.410000 3.950000 19.360000 ( 19.426081)
ruby 1.9.1p0 (2009-01-30 revision 21907) [i686-linux]
Rehearsal -------------------------------------------------------
inline 4.470000 0.000000 4.470000 ( 4.502066)
separate 4.450000 0.000000 4.450000 ( 4.466547)
out of the loop 4.460000 0.000000 4.460000 ( 4.473198)
--------------------------------------------- total: 13.380000sec
user system total real
inline 4.470000 0.000000 4.470000 ( 4.490634)
separate 4.470000 0.000000 4.470000 ( 4.480428)
out of the loop 4.450000 0.000000 4.450000 ( 4.506627)
[robert@ora01 ~]$ cat rx.rb
require 'benchmark'
REP = 10_000
text = ("foo bar baz " * 1_000).freeze
Benchmark.bmbm 20 do |bm|
bm.report "inline" do
REP.times do
text.scan(/bar/) do |match|
match.length
end
end
end
bm.report "separate" do
REP.times do
rx = /bar/
text.scan(rx) do |match|
match.length
end
end
end
bm.report "out of the loop" do
rx = /bar/
REP.times do
text.scan(rx) do |match|
match.length
end
end
end
end
[robert@ora01 ~]$
Cheers
robert
On 18.03.2009 19:12, Eleanor McHugh wrote:
On 18 Mar 2009, at 16:25, Robert Klemme wrote:
2009/3/17 Eleanor McHugh <eleanor@games-with-brains.com>:
spaces = /\s+/
chars = /[^A-Za-z0-9\s]/This is generally less efficient and AFAIK there are no memory leaks
attached to this. It's a different story with varying regular
expressions (i.e. based on input or configuration). But in this case
I'd leave them in place.Interesting, I'll have to do some tests to see what the difference is in practice as this is a code pattern I use a lot.
Hi,
Well I replaced the Nokogiri::HTML with a Hpricot an now my Ram usage
remains below 2% during the whole process.
--
Posted via http://www.ruby-forum.com/.
Edouard Dantes wrote:
Hi,
Well I replaced the Nokogiri::HTML with a Hpricot an now my Ram usage remains below 2% during the whole process.
I hope you'll report this issue to the Nokogiri developer(s) so that they can investigate the problem. I'm sure they will want to hear from you. If it's something they can fix, it will not only help you, it will benefit the entire community.
Report it and then post here what happened.
--
RMagick: http://rmagick.rubyforge.org/
I ran this:
require 'nokogiri'
html = File.read(ARGV[0])
while true
Nokogiri::HTML(html).css('div a').map{ |dts|
dts.text.gsub(/\s+/,"").gsub(/[^A-Za-z0-9\s]/,'Z')
}
end
vs this:
require 'hpricot'
html = File.read(ARGV[0])
while true
Hpricot(html).search('div a').map{ |dts|
next unless dts.respond_to?(:text)
dts.text.gsub(/\s+/,"").gsub(/[^A-Za-z0-9\s]/,'Z')
}
end
As I expected, both were stable and neither leaked memory. What version of
libxml2 are you running? Also, what version of ruby? It could also be
the html I'm parsing... :-\
On Thu, Mar 19, 2009 at 06:04:51AM +0900, Edouard Dantes wrote:
Hi,
Well I replaced the Nokogiri::HTML with a Hpricot an now my Ram usage
remains below 2% during the whole process.
--
Aaron Patterson
http://tenderlovemaking.com/
Aaron Patterson wrote:
libxml2 are you running? Also, what version of ruby? It could also be
the html I'm parsing... :-\
Hi,
I run libxml2 2.7.1 & ruby 1.8.7 patchlevel 72 x86-64
I 've emailed my code to your gmail address.
regards,
--
Posted via http://www.ruby-forum.com/\.