Alexander Motin 49bb454120 FreeBSD: Hardcode abd_chunk_size to PAGE_SIZE ... It makes no sense to set it below PAGE_SIZE, since it increases all overheads and makes returning memory to OS problematic. It makes no sense to set it above PAGE_SIZE, since such allocations and especially frees are too expensive and cause KVA fragmentation to benefit from fewer chunks. After that it makes no sense to keep more complicated math here. What may have sense though is just a tunable border between linear and scatter ABDs, previously also controlled by this tunable. Retain that functionality by taking abd_scatter_min_size tunable from Linux, just with different default value. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Reviewed-by: Brian Atkinson <batkinson@lanl.gov> Reviewed-by: Ryan Moeller <ryan@iXsystems.com> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Closes #12328		2021-09-14 12:36:44 -07:00
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freebsd	FreeBSD: Hardcode abd_chunk_size to PAGE_SIZE	2021-09-14 12:36:44 -07:00
linux	Fix abd leak, kmem_free correct size of abd_t	2021-09-14 12:22:28 -07:00