possible memory leak?

GetURLS.rb

#!/usr/local/bin/ruby
require 'net/http'
require 'open-uri'
require 'nokogiri'
require 'json'
require 'sequel'
class String
  def string_between_markers marker1, marker2
    self[/#{Regexp.escape(marker1)}(.*?)#{Regexp.escape(marker2)}/m, 1]
  end
end
require '/Users/elemenopy/Documents/WTBWTSRubyScripts/WebScrapeClass.rb'
def open(url)
    Net::HTTP.get(URI.parse(url))
end

def iscurrentthread thread, postdate

  db = Sequel.connect(:adapter => 'mysql', :user => 'root', :host => 'localhost', :database => 'wtbwtspoe',:password=>'')
  countofitems = db[:ThreadTable].where(:ThreadURL=>thread, :PostDate=>postdate).count
  db.disconnect
  if countofitems > 0
    return true
  else
    return false
  end
end

def runrootlevelscrape (rootlevelstring,region)
  i = 1
lastpage = 21
while i < lastpage do
  threadurl = rootlevelstring + i.to_s
  puts threadurl
page_content = open(threadurl)
doc = Nokogiri::HTML(page_content)

htmlmastertable = doc.xpath("//table[@class='forumTable viewForumTable']")



htmlmastertable.xpath("//tr").each_with_index do |trrow,index|
  currentindex = "#{index}"
  anchorselect = trrow.xpath("//tr[" + currentindex + "]" + "/td[@class='thread']/div[@class='thread_title']/div[@class='title']/a")
  postdate = trrow.xpath("//tr[" + currentindex + "]" + "/td[@class='last_post']/span[@class='post_date']")
  
  posttitle = anchorselect.text
  posturl = ""
  trrow.xpath("//tr[" + currentindex + "]" + "/td[@class='thread']/div[@class='thread_title']/div[@class='title']/a[@href]").each do |link|
    posturl = link['href']
  end
  
  
  if region == "Garena"
    posturl = "http://web.poe.garena.com/" + posturl
  else
    posturl = "http://www.pathofexile.com" + posturl
  end
  

  postdate = postdate.inner_html.strip
  
  
  if postdate != ""
    iscurrent = iscurrentthread(posturl,postdate)

    if iscurrent == true
      puts "Skipping this thread we already have it"
    else
      puts "New Thread Detected Scraping Now"
      page = WebPage.new() 
      page.scrapepage(posturl,rootlevelstring,i.to_s,region,postdate)
    end
    
  end
  
  
end
  i+=1
end


end



loop do

t1=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/standard-trading-shops/page/","Original")}
t2=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/standard-trading-selling/page/","Original")}
t3=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/hardcore-trading-shops/page/","Original")}
t4=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/hardcore-trading-selling/page/","Original")}
#t5=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/548/page/","Original")}
#t6=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/550/page/","Original")}
##t7=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/549/page/","Original")}
#t8=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/551/page/","Original")}
#t9=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/552/page/","Original")}
#t10=Thread.new{runrootlevelscrape("http://www.pathofexile.com/forum/view-forum/553/page/","Original")}

t11=Thread.new{runrootlevelscrape("http://web.poe.garena.com/forum/view-forum/standard-shops/page/","Garena")}
t12=Thread.new{runrootlevelscrape("http://web.poe.garena.com/forum/view-forum/standard-sell/page/","Garena")}
t13=Thread.new{runrootlevelscrape("http://web.poe.garena.com/forum/view-forum/hardcore-shops/page/","Garena")}
t14=Thread.new{runrootlevelscrape("http://web.poe.garena.com/forum/view-forum/hardcore-sell/page/","Garena")}
#t15=Thread.new{runrootlevelscrape("http://web.poe.garena.com/forum/view-forum/beyond-selling/page/","Garena")}
#t16=Thread.new{runrootlevelscrape("http://web.poe.garena.com/forum/view-forum/beyond-shops/page/","Garena")}
#t17=Thread.new{runrootlevelscrape("http://web.poe.garena.com/forum/view-forum/rampage-shops/page/","Garena")}
#t18=Thread.new{runrootlevelscrape("http://web.poe.garena.com/forum/view-forum/rampage-sell/page/","Garena")}



t1.join
t2.join
t3.join
t4.join
#t5.join
#t6.join
#t7.join
#t8.join
#t9.join
#t10.join


t11.join
t12.join
t13.join
t14.join
#t15.join
#t16.join
#t17.join
#t18.join



Thread.kill(t1)
Thread.kill(t2)
Thread.kill(t3)
Thread.kill(t4)
Thread.kill(t11)
Thread.kill(t12)
Thread.kill(t13)
Thread.kill(t14)






end

WebScrapeClass.rb

class WebPage  
  def initialize()  
   
  end  
  
class Nokogiri::XML::Document
  def remove_empty_lines!
    self.xpath("//text()").each { |text| text.content = text.content.gsub(/\n(\s*\n)+/,"\n") }; self
  end
end
def open(url)
    Net::HTTP.get(URI.parse(url))
end


  def scrapepage(threadurl,rootlevelstring,pagenumber,region,postdate)  
    puts "Running Root Level of: " + rootlevelstring + " on page number: " + pagenumber.to_s + " and forum URL of: " + threadurl
require 'net/http'
require 'open-uri'
require 'nokogiri'
require 'json'
require 'sequel'
histogram = Hash.new(0)





page_content = open(threadurl)
doc = Nokogiri::HTML(page_content)
unless doc.xpath('//table[@class="forumTable forumPostListTable"]/tr/td/div[@class="content"]').first.nil?
firstpostonpage = doc.xpath('//table[@class="forumTable forumPostListTable"]/tr/td/div[@class="content"]').first
firstpostonpage.xpath('//br').find_all.each do |br|
  br.remove
end


postedbyblock = doc.xpath('//div[@class="posted-by"]')


twitchfull = ""
twitchusername = ""
if postedbyblock.xpath('//a[@class="twitch"]') != nil
  twitchfull = postedbyblock.xpath('//a[@class="twitch"]/@href')
twitchfullurllength = twitchfull.to_s.length
twitchusername = twitchfull.to_s[21..-1]
if twitchfullurllength > 50
 twitchusername = ""
else
  puts "added twitch user"
end
end

username = ""

if doc.xpath('//span[@class="profile-link post_by_account"]').first != nil
spanlink = spanlink = doc.xpath('//span[@class="profile-link post_by_account"]').first
username = spanlink.text
end

buyouts = Array.new

firstpostonpage.xpath('//div[starts-with(@id, "item-frag")]').each { |x| 

  rowitem = Array.new([x['id'],x.next])
  buyouts.push(rowitem)
  }


buyouts.each_with_index {
  |x,index|
  currentindex = "#{index}"

}


str1_markerstring = "function(R) { (new R("
str2_markerstring = ")).run(); });"
middletext = page_content.string_between_markers(str1_markerstring,str2_markerstring)
if middletext != nil
  jsonvariable_hash = JSON.parse(middletext)

db = Sequel.connect(:adapter => 'mysql', :user => 'root', :host => 'localhost', :database => 'wtbwtspoe',:password=>'')
threadcollection = db[:ThreadTable]
db[:ItemTable].where(:ThreadURL=>threadurl).delete
threadcollection.where(:ThreadURL=>threadurl).delete
threadcollection.insert(:ThreadURL=>threadurl,:PostDate=>postdate)

jsonvariable_hash.each_with_index do |child,index|
  
  itemsindex = "#{index}"
  verified = child[1]["verified"]
  imageurl = child[1]["icon"]
  support = child[1]["support"]
  league = child[1]["league"]
  itemname = child[1]["name"]
  typeline = child[1]["typeLine"]
  identified = child[1]["identified"]
  corrupted = child[1]["corrupted"]
  implicitmods = child[1]["implicitMods"]
  explicitmodhash = child[1]["explicitMods"]
  flavourtext = child[1]["flavourtext"]
  buyout = buyouts[itemsindex.to_i][1].to_s
  buyout.to_s.gsub("\n","")
  if buyout =~ /^<div class/
    
    buyout = ""
    
  end
  descrText = child[1]["descrText"].to_s
  if support==false
    itemname = typeline  
  end
  if descrText =~ /^This is a Support Gem/ 
    itemname = typeline
  end
  if region == "Garena"
    imageurl = "http://webcdn.pathofexile.com"+ imageurl
  end
  items = db[:ItemTable]
  returnedid = items.insert(:Username=>'NA',:ThreadURL=>threadurl,:Verified=>verified,:IconURL=>imageurl,:League=>league,
  :ItemName=>itemname,:ItemType=>typeline,:Identified=>identified,:Corrupted=>corrupted,
  :FlavourText=>flavourtext,:Sockets=>'',:Properties=>'',:Requirements=>1,:Buyout=>buyout,:Region=>region,:ImplicitMod=>implicitmods,:twitchusername=>twitchusername)

  if explicitmodhash != nil
    explicitmodhash.each do |expmod|
    values = expmod.split(" ",2)
    modvalue = values[0]
    modtype = values[1]
    explicitmods = db[:ExplicitModTable]
    explicitmods.insert(:ItemTableID=>returnedid,:ModValue=>modvalue,:ModType=>modtype)
  
  end
  end
  db.disconnect

end
end
end  
end
end