From 329012f5132172305d68d37c5e6d36a6a00776ef Mon Sep 17 00:00:00 2001 From: Andriy Gapon Date: Wed, 9 Oct 2019 11:34:16 +0000 Subject: zfs: document large_dnode feature The text is copied from illumos. The conversion to mdoc is mine. The FreeBSD boot warning is copied from large_block description. MFC after: 4 days --- .../contrib/opensolaris/cmd/zpool/zpool-features.7 | 30 ++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'cddl/contrib/opensolaris/cmd') diff --git a/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 b/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 index 1d6a6f888730..feb91ca4eb46 100644 --- a/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 +++ b/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 @@ -527,6 +527,36 @@ Please note that booting from datasets that have recordsize greater than supported by the .Fx boot loader. +.It Sy large_dnode +.Bl -column "READ\-ONLY COMPATIBLE" "org.zfsonlinux:large_dnode" +.It GUID Ta org.zfsonlinux:large_dnode +.It READ\-ONLY COMPATIBLE Ta no +.It DEPENDENCIES Ta extensible_dataset +.El +.Pp +The +.Sy large_dnode +feature allows the size of dnodes in a dataset to be set larger than 512B. +.Pp +This feature becomes +.Sy active +once a dataset contains an object with a dnode larger than 512B, +which occurs as a result of setting the +.Sy dnodesize +dataset property to a value other than +.Sy legacy . +The feature will return to being +.Sy enabled +once all filesystems that have ever contained a dnode larger than 512B are +destroyed. +Large dnodes allow more data to be stored in the bonus buffer, thus potentially +improving performance by avoiding the use of spill blocks. +.Pp +Please note that booting from datasets that have dnodes larger than 512B is +.Em NOT +supported by the +.Fx +boot loader. .It Sy sha512 .Bl -column "READ\-ONLY COMPATIBLE" "org.illumos:sha512" .It GUID Ta org.illumos:sha512 -- cgit v1.2.3