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start [2020/06/12 15:58] Ira Weiny [Filesystems] |
start [2020/06/12 15:58] (current) Ira Weiny [Filesystems] |
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==== iostats ==== | ==== iostats ==== | ||
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- | iostats are disabled by default due to performance overhead (e.g., 12M IOPS dropping 25% to 9M IOPS). However, they can be enabled in sysfs if desired. | + | iostats are disabled by default due to performance overhead (e.g., 12M IOPS dropping 25% to 9M IOP |
+ | S). However, they can be enabled in sysfs if desired. | ||
As of kernel 4.5, iostats are only collected for the base pmem device, not per-partition. Also, I/Os that go through DAX paths (rw_page, rw_bytes, and direct_access functions) are not counted, so nothing is collected for: | As of kernel 4.5, iostats are only collected for the base pmem device, not per-partition. Also, I/Os that go through DAX paths (rw_page, rw_bytes, and direct_access functions) are not counted, so nothing is collected for: |