![]() The Btrfs Snappy compression implementation is based upon the Btrfs LZO implementation. This is now a new compression alternative to LZO within the kernel that other software components could also utilize. In moving it to the kernel, Andi Kleen ported the original code from C++ to C as well as made other changes to make it more suitable for the Linux kernel. ![]() Andi Kleen as a result has added Snappy interface to the Linux kernel Crypto API and then dropped in the Snappy implementation as a library in just over one thousand lines of code. ![]() In order for the Btrfs file-system to support Snappy compression, it must be implemented in the kernel, which up until has not been within the kernel tree. On a single core of a Core i7 processor in 64-bit mode, Snappy compresses at about 250 MB/sec or more and decompresses at about 500 MB/sec or more. For instance, compared to the fastest mode of zlib, Snappy is an order of magnitude faster for most inputs, but the resulting compressed files are anywhere from 20% to 100% bigger. It does not aim for maximum compression, or compatibility with any other compression library instead, it aims for very high speeds and reasonable compression. Snappy is a compression/decompression library. For those not familiar with Snappy, additional information is available from its Google Code page. Snappy is a compress/decompression library that Google open-sourced in 2011 after this compression method has already played a vital role within Google with deployments ranging from use in their BigTable and MapReduce to their internal RPC systems. "Should be ready for pulling into the btrfs tree now," Kleen says. ![]() snappy is a faster compression algorithm that provides similar compression as LZO, but generally better performance." "Here's a slightly updated version of the BTRFS snappy interface. This value affects both compression speed and compression ratio: larger blocks can be slower and better compressed.New patches have been published for the Btrfs file-system that implement support for Google's Snappy compression algorithm, which promises to deliver better performance beyond LZO compression.Īndi Kleen of Intel has posted his updated Btrfs snappy compression patches, which he says are now ready for merging. When choosing the logical block size, consider the minimum of all the platforms that will access the files directly – otherwise you may encounter disk compression - bad logicalBlockSize. Windows seems to have a default allocation granularity of 64kB. Logical block sizeĪ power of 2 between 12 and 20: pageSize or allocation granularity to 1MB.
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