Local Cache with large page size cause Out of heap memory

[LuQQiu]

Alluxio Version: Dora branch - 2.10.0-SNAPSHOT

Describe the bug Local cache hit read is zero copy. Local cache with FUSE SDK read is double copy at least:

byte[] page = LocalCacheFileInStream.readExternalPage(position, readType);

• UfsFileInStream.create()
• UfsFileInStream.seek()
• byte[] page = new byte[pageSize]; ← first copy, full page size = 512MB
• ByteBuffer.wrap(page)
• UfsFileInStream.read(ByteBuffer)
• • byte[] byteArray = new byte[len]; <-- second copy, full page size = 512MB
• • read(byte[] b, int off, int len)

To Reproduce Change page size to 512MB launch Fuse SDK with local cache Run FIO big file read: fio --name=sequentialread --rw=read --bs=4m --numjobs=1 --filesize=1g -direct=1 --group_reporting --nrfiles 1

read failed because out of heap memory

Expected behavior A clear and concise description of what you expected to happen.

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[HelloHorizon]

@LuQQiu should we close this issue?

[github-actions[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in two weeks if no further activity occurs. Thank you for your contributions.

[apc999]

@LuQQiu is this still an issue in 30x ?