diff options
Diffstat (limited to 'bugs/struct_calcsize_vs_len_struct_pack.mdwn')
| -rw-r--r-- | bugs/struct_calcsize_vs_len_struct_pack.mdwn | 68 |
1 files changed, 0 insertions, 68 deletions
diff --git a/bugs/struct_calcsize_vs_len_struct_pack.mdwn b/bugs/struct_calcsize_vs_len_struct_pack.mdwn deleted file mode 100644 index 6f77c4c..0000000 --- a/bugs/struct_calcsize_vs_len_struct_pack.mdwn +++ /dev/null @@ -1,68 +0,0 @@ -A small performance improvement on startup may be possible by replacing len(key('',0,0)) with struct.calcsize(self.fmt): - - python -m timeit -s \ - 'import struct; checksum_length = 32; fmt = "!%dsQQ" % checksum_length'\ - 'struct.calcsize(fmt)' - 1000000 loops, best of 3: 0.201 usec per loop - -vs - - python -m timeit -s \ - 'import struct; checksum_length = 32; fmt = "!%dsQQ" % checksum_length'\ - 'len(struct.pack(fmt,"",0,0))' - 1000000 loops, best of 3: 0.753 usec per loop - -I can't attach files, so I can't attach the bundle I think you prefer, but here's the diff, and I'll email you the bundle as an attachment. - - === modified file 'obnamlib/checksumtree.py' - --- obnamlib/checksumtree.py 2011-07-26 13:23:55 +0000 - +++ obnamlib/checksumtree.py 2013-02-08 07:09:22 +0000 - @@ -33,7 +33,7 @@ - upload_queue_size, lru_size, hooks): - tracing.trace('new ChecksumTree name=%s' % name) - self.fmt = '!%dsQQ' % checksum_length - - key_bytes = len(self.key('', 0, 0)) - + key_bytes = struct.calcsize(self.fmt) - obnamlib.RepositoryTree.__init__(self, fs, name, key_bytes, node_size, - upload_queue_size, lru_size, hooks) - self.keep_just_one_tree = True - - === modified file 'obnamlib/chunklist.py' - --- obnamlib/chunklist.py 2011-07-26 13:23:55 +0000 - +++ obnamlib/chunklist.py 2013-02-08 07:09:22 +0000 - @@ -35,14 +35,15 @@ - - def __init__(self, fs, node_size, upload_queue_size, lru_size, hooks): - tracing.trace('new ChunkList') - - self.key_bytes = len(self.key(0)) - + self.fmt = '!Q' - + self.key_bytes = struct.calcsize(self.fmt) - obnamlib.RepositoryTree.__init__(self, fs, 'chunklist', self.key_bytes, - node_size, upload_queue_size, - lru_size, hooks) - self.keep_just_one_tree = True - - def key(self, chunk_id): - - return struct.pack('!Q', chunk_id) - + return struct.pack(self.fmt, chunk_id) - - def add(self, chunk_id, checksum): - tracing.trace('chunk_id=%s', chunk_id) - - === modified file 'obnamlib/clientlist.py' - --- obnamlib/clientlist.py 2011-07-26 13:23:55 +0000 - +++ obnamlib/clientlist.py 2013-02-08 07:09:22 +0000 - @@ -49,7 +49,7 @@ - tracing.trace('new ClientList') - self.hash_len = len(self.hashfunc('')) - self.fmt = '!%dsQB' % self.hash_len - - self.key_bytes = len(self.key('', 0, 0)) - + self.key_bytes = struct.calcsize(self.fmt) - self.minkey = self.hashkey('\x00' * self.hash_len, 0, 0) - self.maxkey = self.hashkey('\xff' * self.hash_len, obnamlib.MAX_ID, - self.SUBKEY_MAX) - - ---- - -Thank you. This has been merged now. [[done]] --liw |