Synchronous writes on SLES 12 are slower than on SLES 11
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In releases until and including SLES 11, only fdatasync(2) is called, which doesn't fully comply with the POSIX specification. In SLE 12, the behavior has changed to match the specification. This can result in notable performance decline of synchronous writes that do not require allocation of new disk space for the file: while previously no inode changes were written in this specific case, inodes now need to be updated because file time stamps have changed and fsync(2) mandates updating inodes in such case while fdatasync(2) does not.
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- Document ID:7016100
- Creation Date: 26-Jan-2015
- Modified Date:03-Mar-2020
- SUSE Linux Enterprise Server
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