Relax special_small_blocks restrictions#17497
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Yeah, this makes sense. Restricting it to a power of two implies it's enforced before compression, which isn't the case. I can see how this would be confusing.
special_small_blocks is applied to blocks after compression, so it makes no sense to demand its values to be power of 2. At most they could be multiple of 512, but that would still buy us nothing, so lets allow them be any within SPA_MAXBLOCKSIZE. Also special_small_blocks does not really need to depend on the set recordsize, enabled pool features or presence of special vdev. At worst in any of those cases it will just do nothing, so we should not complicate users lives by artificial limitations. While there, polish comments for recordsize and volblocksize. Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc.
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special_small_blocks is applied to blocks after compression, so it makes no sense to demand its values to be power of 2. At most they could be multiple of 512, but that would still buy us nothing, so lets allow them be any within SPA_MAXBLOCKSIZE. Also special_small_blocks does not really need to depend on the set recordsize, enabled pool features or presence of special vdev. At worst in any of those cases it will just do nothing, so we should not complicate users lives by artificial limitations. While there, polish comments for recordsize and volblocksize. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc. Closes openzfs#17497
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special_small_blocks is applied to blocks after compression, so it makes no sense to demand its values to be power of 2. At most they could be multiple of 512, but that would still buy us nothing, so lets allow them be any within SPA_MAXBLOCKSIZE. Also special_small_blocks does not really need to depend on the set recordsize, enabled pool features or presence of special vdev. At worst in any of those cases it will just do nothing, so we should not complicate users lives by artificial limitations. While there, polish comments for recordsize and volblocksize. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc. Closes openzfs#17497
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special_small_blocks is applied to blocks after compression, so it makes no sense to demand its values to be power of 2. At most they could be multiple of 512, but that would still buy us nothing, so lets allow them be any within SPA_MAXBLOCKSIZE. Also special_small_blocks does not really need to depend on the set recordsize, enabled pool features or presence of special vdev. At worst in any of those cases it will just do nothing, so we should not complicate users lives by artificial limitations. While there, polish comments for recordsize and volblocksize. Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Alexander Motin <mav@FreeBSD.org> Sponsored by: iXsystems, Inc. Closes openzfs#17497
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special_small_blocksis applied to blocks after compression, so it makes no sense to demand its values to be power of 2. At most they could be multiple of 512, but that would still buy us nothing, so lets allow them be any withinSPA_MAXBLOCKSIZE.Also
special_small_blocksdoes not really need to depend on the setrecordsize, enabled pool features or presence of special vdev. At worst in any of those cases it will just do nothing, so we should not complicate users lives by artificial limitations.While there, polish comments for recordsize and volblocksize.
How Has This Been Tested?
Created a pool without special vdev and set
special_small_blocksto odd value.Types of changes
Checklist:
Signed-off-by.