diff options
author | nahi <nahi@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2011-12-20 14:56:07 +0000 |
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committer | nahi <nahi@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2011-12-20 14:56:07 +0000 |
commit | fcec6b5c0d72288aebce9b18e25e6e92772a2eb8 (patch) | |
tree | 3ab94fdf5dc00b22847fdb80f8651504cd56227b /lib/pstore.rb | |
parent | 5aea2ad18c622cfa5bb53f1d94e058ac7fc41ad3 (diff) |
* PStore content update perf optimization. Patch by Masaki Matsushita.
See #5248.
* lib/pstore.rb (save_data):
* Delete inadequate Marshal check.
* Deferred file truncation: when writing the new content, truncate
the saved file to the data size after writing the data, instead of
truncating whole bytes before writing data.
* Deferred MD5 calculation: when comparing MD5 hash to check the
content modification, calculate MD5 hash of new data iif the
content length is differ from the old one.
* Compare content size with String#bytesize instead of String#size.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@34083 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'lib/pstore.rb')
-rw-r--r-- | lib/pstore.rb | 34 |
1 files changed, 5 insertions, 29 deletions
diff --git a/lib/pstore.rb b/lib/pstore.rb index 952445fc93..8f31687c52 100644 --- a/lib/pstore.rb +++ b/lib/pstore.rb @@ -402,11 +402,11 @@ class PStore # This seems to be a newly-created file. table = {} checksum = empty_marshal_checksum - size = empty_marshal_data.size + size = empty_marshal_data.bytesize else table = load(data) checksum = Digest::MD5.digest(data) - size = data.size + size = data.bytesize if !table.is_a?(Hash) raise Error, "PStore file seems to be corrupted." end @@ -427,34 +427,10 @@ class PStore is_windows end - # Check whether Marshal.dump supports the 'canonical' option. This option - # makes sure that Marshal.dump always dumps data structures in the same order. - # This is important because otherwise, the checksums that we generate may differ. - def marshal_dump_supports_canonical_option? - begin - Marshal.dump(nil, -1, true) - result = true - rescue - result = false - end - self.class.instance_method(:marshal_dump_supports_canonical_option?) - self.class.__send__(:define_method, :marshal_dump_supports_canonical_option?) do - result - end - result - end - def save_data(original_checksum, original_file_size, file) - # We only want to save the new data if the size or checksum has changed. - # This results in less filesystem calls, which is good for performance. - if marshal_dump_supports_canonical_option? - new_data = Marshal.dump(@table, -1, true) - else - new_data = dump(@table) - end - new_checksum = Digest::MD5.digest(new_data) + new_data = dump(@table) - if new_data.size != original_file_size || new_checksum != original_checksum + if new_data.bytesize != original_file_size || Digest::MD5.digest(new_data) != original_checksum if @ultra_safe && !on_windows? # Windows doesn't support atomic file renames. save_data_with_atomic_file_rename_strategy(new_data, file) @@ -484,8 +460,8 @@ class PStore def save_data_with_fast_strategy(data, file) file.rewind - file.truncate(0) file.write(data) + file.truncate(data.bytesize) end |