JDK-8202261 : (fc) FileChannel.map and RandomAccessFile.setLength should not preallocate space
  • Type: Bug
  • Component: core-libs
  • Sub-Component: java.nio
  • Affected Version: 8u181,9,10,11
  • Priority: P2
  • Status: Closed
  • Resolution: Fixed
  • Submitted: 2018-04-25
  • Updated: 2019-05-13
  • Resolved: 2018-04-26
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JDK 11 JDK 8
11 b12Fixed 8u202Fixed
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This issue tracks reverting the changes in JDK-8168628 so that RandomAccessFile.setLength and the FileChannel.map do not call ftruncate64 to pre-allocate disk space. The background to this issue is that JDK-8168628 was mis-diagnosed, the real issue is that bulk transfer operations using Unsafe copyMemory lack memory guards. This requires changes in HotSpot and is tracked as JDK-8191278.

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