btrfs : introduction and performance evaluation
DESCRIPTION
btrfs : Introduction and Performance Evaluation. Douglas Fuller Oak Ridge Leadership Computing Facility / ORNL LUG 2011. btrfs : overview. Implemented in Linux 2.6.29 64-bit Extent-based Copy on write Multiple devices Object pools (RAID-0, RAID-1, and RAID-10 for now) - PowerPoint PPT PresentationTRANSCRIPT
btrfs: Introduction and Performance Evaluation
Douglas FullerOak Ridge Leadership Computing Facility / ORNLLUG 2011
2 Managed by UT-Battellefor the U.S. Department of Energy
btrfs: overview
• Implemented in Linux 2.6.29• 64-bit• Extent-based• Copy on write• Multiple devices– Object pools (RAID-0, RAID-1, and RAID-10 for now)– Dynamic rebalancing
• Subvolumes with snapshots• Available transparent compression (zlib)
3 Managed by UT-Battellefor the U.S. Department of Energy
btrfs: still to come
• Erasure coding (RAID-5/RAID-6)• fsck• Dedup• Encryption
4 Managed by UT-Battellefor the U.S. Department of Energy
Goals
• Determine baseline btrfs performance• Evaluate pooling at the filesystem layer– Avoids expensive RAID controllers– Provides additional features
• Evaluate overhead from additional features
5 Managed by UT-Battellefor the U.S. Department of Energy
Test Platform
• Target: LSI Engenio (xbb2), 1TB fibre channel disks– DDR InfiniBand– Each disk on a separate backend channel– Controller write cache disabled– O_DIRECT– 1MB request sizes– I/O elevator noop
• Initiator– Nehalem with Linux 2.6.37– SRP
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Baseline Performance
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Raw
LUNsDisks
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Sequential write
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Sequential Write
btrfs-multibtrfs-singleext3
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Sequential read
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Sequential Read
btrfs-singlebtrfs-multiext3
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Random write
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Random Write
btrfs-singlebtrfs-multiext3
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Random Read
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Random Read
btrfs-singlebtrfs-multiext3
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Untar
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untar
btrfs-singlebtrfs-single-rbtrfs-multibtrfs-multi-rext3
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Untar with compression
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untar
uncompressedsinglesingle-rmultimulti-r
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Random reads with compression
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Random Read
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Random write with compression
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Random Write
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