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Good job and clean website interface! Something as exhaustive as this is clearly needed. Some remarks: 1. Why does the CoW button remove XFS from the list? Ev

Good job and clean website interface! Something as exhaustive as this is clearly needed. Some remarks: 1. Why does the CoW button remove XFS from the list? Even https://github.com/fenio/modern-fs-benchmark/blob/main/scripts/fs/xfs.sh https://github.com/fenio/modern-fs-benchmark/blob/main/scrip... mentions it has reflink enabled 2. If you have the time, adding XFS + mdraid + dm-integrity [1] (in bitmap mode) as a comparison point against ZFS RAID-Zx might be an interesting data point. That's what I run, personally. 3. Did you give some thoughts to the I/O scheduler choice? Might matter a lot in some cases. [1] https://www.kernel.org/doc/html/latest/admin-guide/device-mapper/dm-integrity.html https://www.kernel.org/doc/html/latest/admin-guide/device-ma...

fenio 6d ago
Thanks, all three are fair points. 1. XFS reflink is enabled and its reflink/CoW-break measurements do run. The dashboard button currently means “native/full-CoW filesystem family”, not “supports reflink”, but that distinction is not clear from the label. I’ll rename it to “Native CoW” and add a separate reflink-capable filter that includes XFS. 2. The current integrity comparison is XFS on LVM/dm-raid10 with dm-integrity in its default journal mode. It is not mdraid and not bitmap mode, so your suggested stack would be a genuinely different and useful data point. An md RAID5/6 over per-member bitmap-mode dm-integrity comparison against RAID-Z1/Z2 makes sense, with the weaker post-crash bitmap semantics documented. 3. I did not pin or record the scheduler, which is a reproducibility gap. The dedicated SAS machine currently has mq-deadline active on all HDDs and SSDs. I’ll add queue/scheduler metadata to results before considering separate scheduler variants, since it can strongly affect the mixed and latency-sensitive phases.

fenio 6d ago

Thanks, all three are fair points. 1. XFS reflink is enabled and its reflink/CoW-break measurements do run. The dashboard button currently means “native/full-CoW filesystem family”, not “supports reflink”, but that distinction is not clear from the label. I’ll rename it to “Native CoW” and add a separate reflink-capable filter that includes XFS. 2. The current integrity comparison is XFS on LVM/dm-raid10 with dm-integrity in its default journal mode. It is not mdraid and not bitmap mode, so your suggested stack would be a genuinely different and useful data point. An md RAID5/6 over per-member bitmap-mode dm-integrity comparison against RAID-Z1/Z2 makes sense, with the weaker post-crash bitmap semantics documented. 3. I did not pin or record the scheduler, which is a reproducibility gap. The dedicated SAS machine currently has mq-deadline active on all HDDs and SSDs. I’ll add queue/scheduler metadata to results before considering separate scheduler variants, since it can strongly affect the mixed and latency-sensitive phases.