#
# Licensed to the Apache Software Foundation (ASF) under one or more
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# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
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__all__ = ["StorageLevel"]
from typing import Any, ClassVar
[docs]class StorageLevel:
"""
Flags for controlling the storage of an RDD. Each StorageLevel records whether to use memory,
whether to drop the RDD to disk if it falls out of memory, whether to keep the data in memory
in a JAVA-specific serialized format, and whether to replicate the RDD partitions on multiple
nodes. Also contains static constants for some commonly used storage levels, MEMORY_ONLY.
Since the data is always serialized on the Python side, all the constants use the serialized
formats.
"""
NONE: ClassVar["StorageLevel"]
DISK_ONLY: ClassVar["StorageLevel"]
DISK_ONLY_2: ClassVar["StorageLevel"]
DISK_ONLY_3: ClassVar["StorageLevel"]
MEMORY_ONLY: ClassVar["StorageLevel"]
MEMORY_ONLY_2: ClassVar["StorageLevel"]
MEMORY_AND_DISK: ClassVar["StorageLevel"]
MEMORY_AND_DISK_2: ClassVar["StorageLevel"]
OFF_HEAP: ClassVar["StorageLevel"]
MEMORY_AND_DISK_DESER: ClassVar["StorageLevel"]
def __init__(
self,
useDisk: bool,
useMemory: bool,
useOffHeap: bool,
deserialized: bool,
replication: int = 1,
):
self.useDisk = useDisk
self.useMemory = useMemory
self.useOffHeap = useOffHeap
self.deserialized = deserialized
self.replication = replication
def __repr__(self) -> str:
return "StorageLevel(%s, %s, %s, %s, %s)" % (
self.useDisk,
self.useMemory,
self.useOffHeap,
self.deserialized,
self.replication,
)
def __str__(self) -> str:
result = ""
result += "Disk " if self.useDisk else ""
result += "Memory " if self.useMemory else ""
result += "OffHeap " if self.useOffHeap else ""
result += "Deserialized " if self.deserialized else "Serialized "
result += "%sx Replicated" % self.replication
return result
def __eq__(self, other: Any) -> bool:
return (
isinstance(other, StorageLevel)
and self.useMemory == other.useMemory
and self.useDisk == other.useDisk
and self.useOffHeap == other.useOffHeap
and self.deserialized == other.deserialized
and self.replication == other.replication
)
StorageLevel.NONE = StorageLevel(False, False, False, False)
StorageLevel.DISK_ONLY = StorageLevel(True, False, False, False)
StorageLevel.DISK_ONLY_2 = StorageLevel(True, False, False, False, 2)
StorageLevel.DISK_ONLY_3 = StorageLevel(True, False, False, False, 3)
StorageLevel.MEMORY_ONLY = StorageLevel(False, True, False, False)
StorageLevel.MEMORY_ONLY_2 = StorageLevel(False, True, False, False, 2)
StorageLevel.MEMORY_AND_DISK = StorageLevel(True, True, False, False)
StorageLevel.MEMORY_AND_DISK_2 = StorageLevel(True, True, False, False, 2)
StorageLevel.OFF_HEAP = StorageLevel(True, True, True, False, 1)
StorageLevel.MEMORY_AND_DISK_DESER = StorageLevel(True, True, False, True)