11684: ArvadosFile.flush() now check if it is the only owner of a bufferblock before...
[arvados.git] / sdk / python / arvados / arvfile.py
index a2ec76a0761cb43a43731e5e31e9638f0dbf3019..a1d87a498ef81304ad6266793292263f8ff4479c 100644 (file)
@@ -1,18 +1,26 @@
-import functools
-import os
-import zlib
+from __future__ import absolute_import
+from __future__ import division
+from future import standard_library
+from future.utils import listitems, listvalues
+standard_library.install_aliases()
+from builtins import range
+from builtins import object
 import bz2
-import config
-import hashlib
-import threading
-import Queue
+import collections
 import copy
 import errno
-import re
+import functools
+import hashlib
 import logging
-import collections
+import os
+import queue
+import re
+import sys
+import threading
 import uuid
+import zlib
 
+from . import config
 from .errors import KeepWriteError, AssertionError, ArgumentError
 from .keep import KeepLocator
 from ._normalize_stream import normalize_stream
@@ -76,7 +84,10 @@ class _FileLikeObjectBase(object):
 class ArvadosFileReaderBase(_FileLikeObjectBase):
     def __init__(self, name, mode, num_retries=None):
         super(ArvadosFileReaderBase, self).__init__(name, mode)
-        self._filepos = 0L
+        self._binary = 'b' in mode
+        if sys.version_info >= (3, 0) and not self._binary:
+            raise NotImplementedError("text mode {!r} is not implemented".format(mode))
+        self._filepos = 0
         self.num_retries = num_retries
         self._readline_cache = (None, None)
 
@@ -96,7 +107,7 @@ class ArvadosFileReaderBase(_FileLikeObjectBase):
             pos += self._filepos
         elif whence == os.SEEK_END:
             pos += self.size()
-        if pos < 0L:
+        if pos < 0:
             raise IOError(errno.EINVAL, "Tried to seek to negative file offset.")
         self._filepos = pos
         return self._filepos
@@ -118,7 +129,7 @@ class ArvadosFileReaderBase(_FileLikeObjectBase):
     def readall(self, size=2**20, num_retries=None):
         while True:
             data = self.read(size, num_retries=num_retries)
-            if data == '':
+            if len(data) == 0:
                 break
             yield data
 
@@ -130,23 +141,23 @@ class ArvadosFileReaderBase(_FileLikeObjectBase):
             data = [cache_data]
             self._filepos += len(cache_data)
         else:
-            data = ['']
+            data = [b'']
         data_size = len(data[-1])
-        while (data_size < size) and ('\n' not in data[-1]):
+        while (data_size < size) and (b'\n' not in data[-1]):
             next_read = self.read(2 ** 20, num_retries=num_retries)
             if not next_read:
                 break
             data.append(next_read)
             data_size += len(next_read)
-        data = ''.join(data)
+        data = b''.join(data)
         try:
-            nextline_index = data.index('\n') + 1
+            nextline_index = data.index(b'\n') + 1
         except ValueError:
             nextline_index = len(data)
         nextline_index = min(nextline_index, size)
         self._filepos -= len(data) - nextline_index
         self._readline_cache = (self.tell(), data[nextline_index:])
-        return data[:nextline_index]
+        return data[:nextline_index].decode()
 
     @_FileLikeObjectBase._before_close
     @retry_method
@@ -181,7 +192,7 @@ class ArvadosFileReaderBase(_FileLikeObjectBase):
             data_size += len(s)
             if data_size >= sizehint:
                 break
-        return ''.join(data).splitlines(True)
+        return b''.join(data).decode().splitlines(True)
 
     def size(self):
         raise IOError(errno.ENOSYS, "Not implemented")
@@ -218,15 +229,15 @@ class StreamFileReader(ArvadosFileReaderBase):
     def read(self, size, num_retries=None):
         """Read up to 'size' bytes from the stream, starting at the current file position"""
         if size == 0:
-            return ''
+            return b''
 
-        data = ''
+        data = b''
         available_chunks = locators_and_ranges(self.segments, self._filepos, size)
         if available_chunks:
             lr = available_chunks[0]
             data = self._stream.readfrom(lr.locator+lr.segment_offset,
-                                          lr.segment_size,
-                                          num_retries=num_retries)
+                                         lr.segment_size,
+                                         num_retries=num_retries)
 
         self._filepos += len(data)
         return data
@@ -236,13 +247,13 @@ class StreamFileReader(ArvadosFileReaderBase):
     def readfrom(self, start, size, num_retries=None):
         """Read up to 'size' bytes from the stream, starting at 'start'"""
         if size == 0:
-            return ''
+            return b''
 
         data = []
         for lr in locators_and_ranges(self.segments, start, size):
             data.append(self._stream.readfrom(lr.locator+lr.segment_offset, lr.segment_size,
                                               num_retries=num_retries))
-        return ''.join(data)
+        return b''.join(data)
 
     def as_manifest(self):
         segs = []
@@ -323,6 +334,8 @@ class _BufferBlock(object):
 
         """
         if self._state == _BufferBlock.WRITABLE:
+            if not isinstance(data, bytes) and not isinstance(data, memoryview):
+                data = data.encode()
             while (self.write_pointer+len(data)) > len(self.buffer_block):
                 new_buffer_block = bytearray(len(self.buffer_block) * 2)
                 new_buffer_block[0:self.write_pointer] = self.buffer_block[0:self.write_pointer]
@@ -544,7 +557,6 @@ class _BlockManager(object):
                 else:
                     loc = self._keep.put(bufferblock.buffer_view[0:bufferblock.write_pointer].tobytes(), copies=self.copies)
                 bufferblock.set_state(_BufferBlock.COMMITTED, loc)
-
             except Exception as e:
                 bufferblock.set_state(_BufferBlock.ERROR, e)
             finally:
@@ -565,10 +577,10 @@ class _BlockManager(object):
                 # blocks pending.  If they are full 64 MiB blocks, that means up to
                 # 256 MiB of internal buffering, which is the same size as the
                 # default download block cache in KeepClient.
-                self._put_queue = Queue.Queue(maxsize=2)
+                self._put_queue = queue.Queue(maxsize=2)
 
                 self._put_threads = []
-                for i in xrange(0, self.num_put_threads):
+                for i in range(0, self.num_put_threads):
                     thread = threading.Thread(target=self._commit_bufferblock_worker)
                     self._put_threads.append(thread)
                     thread.daemon = True
@@ -588,9 +600,9 @@ class _BlockManager(object):
     @synchronized
     def start_get_threads(self):
         if self._prefetch_threads is None:
-            self._prefetch_queue = Queue.Queue()
+            self._prefetch_queue = queue.Queue()
             self._prefetch_threads = []
-            for i in xrange(0, self.num_get_threads):
+            for i in range(0, self.num_get_threads):
                 thread = threading.Thread(target=self._block_prefetch_worker)
                 self._prefetch_threads.append(thread)
                 thread.daemon = True
@@ -633,12 +645,13 @@ class _BlockManager(object):
         if not (force or (self._pending_write_size >= config.KEEP_BLOCK_SIZE)):
             return
 
-        # Search blocks ready for getting packed together before being committed to Keep.
+        # Search blocks ready for getting packed together before being
+        # committed to Keep.
         # A WRITABLE block always has an owner.
-        # A WRITABLE block with its owner.closed() implies that it's
+        # A WRITABLE block with its owner.closed() implies that its
         # size is <= KEEP_BLOCK_SIZE/2.
         try:
-            small_blocks = [b for b in self._bufferblocks.values()
+            small_blocks = [b for b in listvalues(self._bufferblocks)
                             if b.state() == _BufferBlock.WRITABLE and b.owner.closed()]
         except AttributeError:
             # Writable blocks without owner shouldn't exist.
@@ -659,9 +672,11 @@ class _BlockManager(object):
             return
 
         new_bb = self._alloc_bufferblock()
+        new_bb.owner = []
         files = []
         while len(small_blocks) > 0 and (new_bb.write_pointer + small_blocks[0].size()) <= config.KEEP_BLOCK_SIZE:
             bb = small_blocks.pop(0)
+            new_bb.owner.append(bb.owner)
             self._pending_write_size -= bb.size()
             new_bb.append(bb.buffer_view[0:bb.write_pointer].tobytes())
             files.append((bb, new_bb.write_pointer - bb.size()))
@@ -672,7 +687,7 @@ class _BlockManager(object):
             newsegs = bb.owner.segments()
             for s in newsegs:
                 if s.locator == bb.blockid:
-                    s.locator = new_bb.locator()
+                    s.locator = new_bb.blockid
                     s.segment_offset = new_bb_segment_offset+s.segment_offset
             bb.owner.set_segments(newsegs)
             self._delete_bufferblock(bb.blockid)
@@ -778,11 +793,14 @@ class _BlockManager(object):
         self.repack_small_blocks(force=True, sync=True)
 
         with self.lock:
-            items = self._bufferblocks.items()
+            items = listitems(self._bufferblocks)
 
         for k,v in items:
             if v.state() != _BufferBlock.COMMITTED and v.owner:
-                v.owner.flush(sync=False)
+                # Ignore blocks with a list of owners, as if they're not in COMMITTED
+                # state, they're already being committed asynchronously.
+                if isinstance(v.owner, ArvadosFile):
+                    v.owner.flush(sync=False)
 
         with self.lock:
             if self._put_queue is not None:
@@ -799,7 +817,15 @@ class _BlockManager(object):
             # flush again with sync=True to remove committed bufferblocks from
             # the segments.
             if v.owner:
-                v.owner.flush(sync=True)
+                if isinstance(v.owner, ArvadosFile):
+                    v.owner.flush(sync=True)
+                elif isinstance(v.owner, list) and len(v.owner) > 0:
+                    # This bufferblock is referenced by many files as a result
+                    # of repacking small blocks, so don't delete it when flushing
+                    # its owners, just do it after flushing them all.
+                    for owner in v.owner:
+                        owner.flush(sync=True)
+                    self.delete_bufferblock(k)
 
     def block_prefetch(self, locator):
         """Initiate a background download of a block.
@@ -910,7 +936,7 @@ class ArvadosFile(object):
         with self.lock:
             if len(self._segments) != len(othersegs):
                 return False
-            for i in xrange(0, len(othersegs)):
+            for i in range(0, len(othersegs)):
                 seg1 = self._segments[i]
                 seg2 = othersegs[i]
                 loc1 = seg1.locator
@@ -970,7 +996,7 @@ class ArvadosFile(object):
         """
         self._writers.remove(writer)
 
-        if flush or self.size() > config.KEEP_BLOCK_SIZE / 2:
+        if flush or self.size() > config.KEEP_BLOCK_SIZE // 2:
             # File writer closed, not small enough for repacking
             self.flush()
         elif self.closed():
@@ -1035,7 +1061,7 @@ class ArvadosFile(object):
 
         with self.lock:
             if size == 0 or offset >= self.size():
-                return ''
+                return b''
             readsegs = locators_and_ranges(self._segments, offset, size)
             prefetch = locators_and_ranges(self._segments, offset + size, config.KEEP_BLOCK_SIZE, limit=32)
 
@@ -1055,7 +1081,7 @@ class ArvadosFile(object):
                 self.parent._my_block_manager().block_prefetch(lr.locator)
                 locs.add(lr.locator)
 
-        return ''.join(data)
+        return b''.join(data)
 
     @must_be_writable
     @synchronized
@@ -1066,6 +1092,8 @@ class ArvadosFile(object):
         necessary.
 
         """
+        if not isinstance(data, bytes) and not isinstance(data, memoryview):
+            data = data.encode()
         if len(data) == 0:
             return
 
@@ -1128,7 +1156,10 @@ class ArvadosFile(object):
                     to_delete.add(s.locator)
                     s.locator = bb.locator()
             for s in to_delete:
-               self.parent._my_block_manager().delete_bufferblock(s)
+                # Don't delete the bufferblock if it's owned by many files. It'll be
+                # deleted after all of its owners are flush()ed.
+                if self.parent._my_block_manager().get_bufferblock(s).owner is self:
+                    self.parent._my_block_manager().delete_bufferblock(s)
 
         self.parent.notify(MOD, self.parent, self.name, (self, self))
 
@@ -1198,8 +1229,8 @@ class ArvadosFileReader(ArvadosFileReaderBase):
 
     """
 
-    def __init__(self, arvadosfile, num_retries=None):
-        super(ArvadosFileReader, self).__init__(arvadosfile.name, "r", num_retries=num_retries)
+    def __init__(self, arvadosfile, mode="r", num_retries=None):
+        super(ArvadosFileReader, self).__init__(arvadosfile.name, mode=mode, num_retries=num_retries)
         self.arvadosfile = arvadosfile
 
     def size(self):
@@ -1223,7 +1254,7 @@ class ArvadosFileReader(ArvadosFileReaderBase):
                 data.append(rd)
                 self._filepos += len(rd)
                 rd = self.arvadosfile.readfrom(self._filepos, config.KEEP_BLOCK_SIZE, num_retries)
-            return ''.join(data)
+            return b''.join(data)
         else:
             data = self.arvadosfile.readfrom(self._filepos, size, num_retries, exact=True)
             self._filepos += len(data)
@@ -1251,8 +1282,7 @@ class ArvadosFileWriter(ArvadosFileReader):
     """
 
     def __init__(self, arvadosfile, mode, num_retries=None):
-        super(ArvadosFileWriter, self).__init__(arvadosfile, num_retries=num_retries)
-        self.mode = mode
+        super(ArvadosFileWriter, self).__init__(arvadosfile, mode=mode, num_retries=num_retries)
         self.arvadosfile.add_writer(self)
 
     def writable(self):
@@ -1262,10 +1292,9 @@ class ArvadosFileWriter(ArvadosFileReader):
     @retry_method
     def write(self, data, num_retries=None):
         if self.mode[0] == "a":
-            self.arvadosfile.writeto(self.size(), data, num_retries)
-        else:
-            self.arvadosfile.writeto(self._filepos, data, num_retries)
-            self._filepos += len(data)
+            self._filepos = self.size()
+        self.arvadosfile.writeto(self._filepos, data, num_retries)
+        self._filepos += len(data)
         return len(data)
 
     @_FileLikeObjectBase._before_close