如何修复由打开引起的死锁
How to fix a deadlock caused by open
我有一个死锁,但我没有在我的程序中使用任何线程。另外,该错误大约每 1000 到 1500 次函数调用才会发生一次,因此很难查明和更正。
这是出现问题时的完整错误消息:
/usr/lib/ruby/2.3.0/timeout.rb:95:in `join': No live threads left. Deadlock? (fatal)
from /usr/lib/ruby/2.3.0/timeout.rb:95:in `ensure in block in timeout'
from /usr/lib/ruby/2.3.0/timeout.rb:95:in `block in timeout'
from /usr/lib/ruby/2.3.0/timeout.rb:101:in `timeout'
from /usr/lib/ruby/2.3.0/net/http.rb:878:in `connect'
from /usr/lib/ruby/2.3.0/net/http.rb:863:in `do_start'
from /usr/lib/ruby/2.3.0/net/http.rb:852:in `start'
from /usr/lib/ruby/2.3.0/open-uri.rb:319:in `open_http'
from /usr/lib/ruby/2.3.0/open-uri.rb:737:in `buffer_open'
from /usr/lib/ruby/2.3.0/open-uri.rb:212:in `block in open_loop'
from /usr/lib/ruby/2.3.0/open-uri.rb:210:in `catch'
from /usr/lib/ruby/2.3.0/open-uri.rb:210:in `open_loop'
from /usr/lib/ruby/2.3.0/open-uri.rb:151:in `open_uri'
from /usr/lib/ruby/2.3.0/open-uri.rb:717:in `open'
from /usr/lib/ruby/2.3.0/open-uri.rb:35:in `open'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/utils.rb:85:in `get_pic'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_download.rb:87:in `page_link'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_download.rb:116:in `chapter_link'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_download.rb:142:in `chapter'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_update.rb:57:in `block in MF_manga_missing_chapters'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_update.rb:45:in `reverse_each'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_update.rb:45:in `MF_manga_missing_chapters'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_update.rb:80:in `MF_update'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:5:in `update_manga'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:15:in `block in update_all'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:14:in `each'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:14:in `update_all'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:22:in `update'
from ./MangaScrap.rb:28:in `<main>'
完整程序的link是https://github.com/Hellfire01/MangaScrap
问题发生在使用 open
的三种不同方法上。这是这次崩溃的那个:
# conect to link and download picture
def get_pic(link)
safe_link = link.gsub(/[\[\]]/) { '%%%s' % $&.ord.to_s(16) }
tries ||= 20
begin
page = open(safe_link, "User-Agent" => "Ruby/#{RUBY_VERSION}")
rescue URI::InvalidURIError => error
puts "Warning : bad url"
puts link
puts "message is : " + error.message
return nil
rescue => error
if tries > 0
tries -= 1
sleep(0.2)
retry
else
puts 'could not get picture ' + safe_link + ' after ' + $nb_tries.to_s + ' tries'
puts "message is : " + error.message
return nil
end
end
sleep(0.2)
return page
end
这是文件的 link:https://github.com/Hellfire01/MangaScrap/blob/master/sources/utils.rb
我想知道:
- 我该如何解决这个错误?
- 如果我无法修复此错误,是否可以使用 OpenUri 的替代方案?
您并未在此处捕获所有异常。当 rescue
之后没有指定任何内容时,这意味着您正在捕获不在异常层次结构根部的 StandardError
。
如果您想确保捕捉到 所有 异常并重试打开 URL(或您想要的任何行为),您想要做的是:
rescue Exception => error
我有一个死锁,但我没有在我的程序中使用任何线程。另外,该错误大约每 1000 到 1500 次函数调用才会发生一次,因此很难查明和更正。
这是出现问题时的完整错误消息:
/usr/lib/ruby/2.3.0/timeout.rb:95:in `join': No live threads left. Deadlock? (fatal)
from /usr/lib/ruby/2.3.0/timeout.rb:95:in `ensure in block in timeout'
from /usr/lib/ruby/2.3.0/timeout.rb:95:in `block in timeout'
from /usr/lib/ruby/2.3.0/timeout.rb:101:in `timeout'
from /usr/lib/ruby/2.3.0/net/http.rb:878:in `connect'
from /usr/lib/ruby/2.3.0/net/http.rb:863:in `do_start'
from /usr/lib/ruby/2.3.0/net/http.rb:852:in `start'
from /usr/lib/ruby/2.3.0/open-uri.rb:319:in `open_http'
from /usr/lib/ruby/2.3.0/open-uri.rb:737:in `buffer_open'
from /usr/lib/ruby/2.3.0/open-uri.rb:212:in `block in open_loop'
from /usr/lib/ruby/2.3.0/open-uri.rb:210:in `catch'
from /usr/lib/ruby/2.3.0/open-uri.rb:210:in `open_loop'
from /usr/lib/ruby/2.3.0/open-uri.rb:151:in `open_uri'
from /usr/lib/ruby/2.3.0/open-uri.rb:717:in `open'
from /usr/lib/ruby/2.3.0/open-uri.rb:35:in `open'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/utils.rb:85:in `get_pic'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_download.rb:87:in `page_link'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_download.rb:116:in `chapter_link'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_download.rb:142:in `chapter'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_update.rb:57:in `block in MF_manga_missing_chapters'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_update.rb:45:in `reverse_each'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_update.rb:45:in `MF_manga_missing_chapters'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/mangafox/MF_update.rb:80:in `MF_update'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:5:in `update_manga'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:15:in `block in update_all'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:14:in `each'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:14:in `update_all'
from /home/mat/travail_perso/RUBY/MangaScrapp_github/sources/update.rb:22:in `update'
from ./MangaScrap.rb:28:in `<main>'
完整程序的link是https://github.com/Hellfire01/MangaScrap
问题发生在使用 open
的三种不同方法上。这是这次崩溃的那个:
# conect to link and download picture
def get_pic(link)
safe_link = link.gsub(/[\[\]]/) { '%%%s' % $&.ord.to_s(16) }
tries ||= 20
begin
page = open(safe_link, "User-Agent" => "Ruby/#{RUBY_VERSION}")
rescue URI::InvalidURIError => error
puts "Warning : bad url"
puts link
puts "message is : " + error.message
return nil
rescue => error
if tries > 0
tries -= 1
sleep(0.2)
retry
else
puts 'could not get picture ' + safe_link + ' after ' + $nb_tries.to_s + ' tries'
puts "message is : " + error.message
return nil
end
end
sleep(0.2)
return page
end
这是文件的 link:https://github.com/Hellfire01/MangaScrap/blob/master/sources/utils.rb
我想知道:
- 我该如何解决这个错误?
- 如果我无法修复此错误,是否可以使用 OpenUri 的替代方案?
您并未在此处捕获所有异常。当 rescue
之后没有指定任何内容时,这意味着您正在捕获不在异常层次结构根部的 StandardError
。
如果您想确保捕捉到 所有 异常并重试打开 URL(或您想要的任何行为),您想要做的是:
rescue Exception => error