diff options
Diffstat (limited to 'cddl/contrib/opensolaris/cmd/zpool/zpool-features.7')
-rw-r--r-- | cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 b/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 index 999212c..2768ef5 100644 --- a/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 +++ b/cddl/contrib/opensolaris/cmd/zpool/zpool-features.7 @@ -18,10 +18,11 @@ .\" information: Portions Copyright [yyyy] [name of copyright owner] .\" .\" Copyright (c) 2012 by Delphix. All rights reserved. +.\" Copyright (c) 2013 by Saso Kiselkov. All rights reserved. .\" .\" $FreeBSD$ .\" -.Dd Aug 28, 2012 +.Dd February 8, 2012 .Dt ZPOOL-FEATURES 7 .Os .Sh NAME @@ -185,6 +186,49 @@ This feature is .Sy active while there are any filesystems, volumes, or snapshots which were created after enabling this feature. +.It Sy lz4_compress +.Bl -column "READ\-ONLY COMPATIBLE" "org.illumos:lz4_compress" +.It GUID Ta org.illumos:lz4_compress +.It READ\-ONLY COMPATIBLE Ta no +.It DEPENDENCIES Ta none +.El +.Pp +.Sy lz4 +is a high-performance real-time compression algorithm that +features significantly faster compression and decompression as well as a +higher compression ratio than the older +.Sy lzjb +compression. +Typically, +.Sy lz4 +compression is approximately 50% faster on +compressible data and 200% faster on incompressible data than +.Sy lzjb . +It is also approximately 80% faster on decompression, while +giving approximately 10% better compression ratio. +.Pp +When the +.Sy lz4_compress +feature is set to +.Sy enabled , +the +administrator can turn on +.Sy lz4 +compression on any dataset on the +pool using the +.Xr zfs 8 +command. Please note that doing so will +immediately activate the +.Sy lz4_compress +feature on the underlying +pool (even before any data is written). Since this feature is not +read-only compatible, this operation will render the pool unimportable +on systems without support for the +.Sy lz4_compress +feature. At the +moment, this operation cannot be reversed. Booting off of +.Sy lz4 +-compressed root pools is supported. .El .Sh SEE ALSO .Xr zpool 8 |