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See http://www.infradead.org/rpr.html X-Rspam-User: X-Stat-Signature: ppch68j7kqbjoh7xdqa9zndwy9o8rbxj X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: 728631C0007 X-HE-Tag: 1701865212-143245 X-HE-Meta: U2FsdGVkX18MrO/ouzBDtbid82nqn/kW646xlSKqi+OAlroUMGuSzYoirabYQn8RUos+6jD5aoYmaquxP8mYsuN5g/Hm12k+Uhg6S6ILTmGv8/RNX/spjsUYIU4wFDTTigJS8Wgi82+w5diKKO9gqdqdYjnMIJpGYDdMu0zwVNqNMfCE3yksAsI5Exjk5hYTGRfjra4Wuh8/+S78/74iRM3vNWrK90bS2GWLtL5bMdRRNnAbvQzc5xwOkwvc6xHIDeJfA757lsKCIM2cBV/AU+VF0beG7GE+OH1nrM7EGycbn/DpErEU5j+A56A4wwKeixJ7ryZj+kkMbJM9XSYFH7FoUa9O3A6s7jQXHiZAgDv0lWx4mgbGN9cQEC9AyWsOtb4qbkcjykUcPwOnRgXeoPz958UcypQOvMawMZpIfjn1Gd+pURBGm0uw6darg0A4LixLwN9YchegVZPTPxanb0i84YZhdkllUbFnBkE4OLe7WQQvakRDWqXoU6VP7knRsco2F7Jb2dmQxh4hKjdCMOikBocfStyFuQ+sYnMq3kZgbS0G9Cfzu+e4a/hdUxcvsZqEgWWNmSQ3EjTV/8ebpeiZ4UJvklbLOqufZw+TVjjgncyoD+/b+uhXZahRF0m8ljB/lXxgVIdOm/AqwBgFCvU4Y3JBqLcKvptnvHD/28a8pPd8g6ROwU1WGv1feCSrK0DpUaXlfEyQB0ILAdNuVl7KkdgPVsqdlnhblEFNKVgJBRpR58AxfT0JhT2tqWPrR7i0T3oXP/LqzKUG5zFlqDVTkqwpNvXddVomJw0Jxn19Sxk5wg8mebYVmxNpkJMBW1+q25Ce0w4IiI9TtJxCHE1fnsPTZPc87GI6a9W+SUIFYFJKZ2aylKlr8SznK7FrYnjlCq4yHK4esZjYw7AqCRdtE/gOLNcZ3nNtet1GgiEFzpReXXFtBUQEI4RVG1axOr+d/DZu6CusKaJYLlJ GbnorEJp fCUj5wkpa2PJPvkd72678/no3e3gZb1/eZiQEPo7xWLBNJ6Ovr4b4X6zPBbkFIc/RqspoHgy62Yh0Nj6KSo0qv5nUFLyargyvtfbwLULlWpo7WwwmktQiZB3in9uxqUv6kv2KwxHsZFxrOlK/mKn5znAw2QX8Z5T+MqheaxjROOO7+hqGgK4EF1f/RyrTSjEIgnso/C4kPp1mgz4pM5V1kJrDHbLnTjFZxayM7OvxI7khgrpierymix5cSfxlKISRORd1XeB+gC3EiaarfmqFYY9riXhuV3VlsLLUvr+GRnsra5QVO/aqZtMuVcDDK1An3Z7ijzu5bsQ7rdfiw02KLL5kiNLGRLl7Q/XYvsBXPUo3J/hZHIfjaOWDW0CY5+j5DucSjY3DevXiJ0UXSiEtVfSwGDF0/ns1u4pC06XLdWo1YTWedZFHziO6542tB1X79Kkf3FFyMvVnQ0RHvYVCCeZ/tg== X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Wed, Dec 06, 2023 at 09:34:49PM +1100, Dave Chinner wrote: > Largely they were performance problems - unpredictable IO latency > and CPU overhead for IO meant applications would randomly miss SLAs. > The application would see IO suddenly lose all concurrency, go real > slow and/or burn lots more CPU when the inode switched to buffered > mode. > > I'm not sure that's a particularly viable model given the raw IO > throughput even cheap modern SSDs largely exceeds the capability of > buffered IO through the page cache. The differences in concurrency, > latency and throughput between buffered and DIO modes will be even > more stark itoday than they were 20 years ago.... The question is what's worse: random performance drops or random corruption. I suspect the former is less bad, especially if we have good tracepoints to pin it down.