Re: [Lsf-pc] [LSF/MM/BPF TOPIC] File system checksum offload

Martin K. Petersen
2025-01-30T20:39:34Z

Ted,

> It's true that relative to not doing checksumming at all, it it's not
> "free". The CPU has to calculate the checksum, so there are power,
> CPU, and memory bandwidth costs. I'd still tend to lean towards
> defaulting it to on, so that the user doesn't need do anything special
> if they have hardware is capable of supporting the data integrity
> feature.

It already works that way. If a device advertises being
integrity-capable, the block layer will automatically generate
protection information on write and verify received protection
information on read. Leveraging hardware-accelerated CRC calculation if
the CPU is capable (PCLMULQDQ, etc.).

--
Martin K. Petersen Oracle Linux Engineering