Merge branch '21639-keep-cache-dict' refs #21639

[arvados.git] / sdk / python / arvados / arvfile.py

diff --git a/sdk/python/arvados/arvfile.py b/sdk/python/arvados/arvfile.py
index 4b95835aac0f25a57fd999a2c5f9cff0e54014e1..0cc7d25a331871c88860357853d1a21898eae965 100644 (file)
--- a/sdk/python/arvados/arvfile.py
+++ b/sdk/python/arvados/arvfile.py
@@ -1060,7 +1060,8 @@ class ArvadosFile(object):
             if size == 0 or offset >= self.size():
                 return b''
             readsegs = locators_and_ranges(self._segments, offset, size)
-            prefetch = locators_and_ranges(self._segments, offset + size, config.KEEP_BLOCK_SIZE * self.parent._my_block_manager()._keep.num_prefetch_threads, limit=32)
+            if self.parent._my_block_manager()._keep.num_prefetch_threads > 0:
+                prefetch = locators_and_ranges(self._segments, offset + size, config.KEEP_BLOCK_SIZE * self.parent._my_block_manager()._keep.num_prefetch_threads, limit=32)
 
         locs = set()
         data = []
@@ -1068,17 +1069,21 @@ class ArvadosFile(object):
             block = self.parent._my_block_manager().get_block_contents(lr.locator, num_retries=num_retries, cache_only=(bool(data) and not exact))
             if block:
                 blockview = memoryview(block)
-                data.append(blockview[lr.segment_offset:lr.segment_offset+lr.segment_size].tobytes())
+                data.append(blockview[lr.segment_offset:lr.segment_offset+lr.segment_size])
                 locs.add(lr.locator)
             else:
                 break
 
-        for lr in prefetch:
-            if lr.locator not in locs:
-                self.parent._my_block_manager().block_prefetch(lr.locator)
-                locs.add(lr.locator)
+        if self.parent._my_block_manager()._keep.num_prefetch_threads > 0:
+            for lr in prefetch:
+                if lr.locator not in locs:
+                    self.parent._my_block_manager().block_prefetch(lr.locator)
+                    locs.add(lr.locator)
 
-        return b''.join(data)
+        if len(data) == 1:
+            return data[0]
+        else:
+            return b''.join(data)
 
     @must_be_writable
     @synchronized