diff options
Diffstat (limited to 'Documentation/device-mapper/thin-provisioning.txt')
| -rw-r--r-- | Documentation/device-mapper/thin-provisioning.txt | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/Documentation/device-mapper/thin-provisioning.txt b/Documentation/device-mapper/thin-provisioning.txt index 3d01948ea061..883e7ca5f745 100644 --- a/Documentation/device-mapper/thin-provisioning.txt +++ b/Documentation/device-mapper/thin-provisioning.txt @@ -28,17 +28,18 @@ administrator some freedom, for example to: Status ====== -These targets are very much still in the EXPERIMENTAL state. Please -do not yet rely on them in production. But do experiment and offer us -feedback. Different use cases will have different performance -characteristics, for example due to fragmentation of the data volume. +These targets are considered safe for production use. But different use +cases will have different performance characteristics, for example due +to fragmentation of the data volume. If you find this software is not performing as expected please mail dm-devel@redhat.com with details and we'll try our best to improve things for you. -Userspace tools for checking and repairing the metadata are under -development. +Userspace tools for checking and repairing the metadata have been fully +developed and are available as 'thin_check' and 'thin_repair'. The name +of the package that provides these utilities varies by distribution (on +a Red Hat distribution it is named 'device-mapper-persistent-data'). Cookbook ======== @@ -280,7 +281,7 @@ ii) Status <transaction id> <used metadata blocks>/<total metadata blocks> <used data blocks>/<total data blocks> <held metadata root> ro|rw|out_of_data_space [no_]discard_passdown [error|queue]_if_no_space - needs_check|- + needs_check|- metadata_low_watermark transaction id: A 64-bit number used by userspace to help synchronise with metadata @@ -327,6 +328,11 @@ ii) Status thin-pool can be made fully operational again. '-' indicates needs_check is not set. + metadata_low_watermark: + Value of metadata low watermark in blocks. The kernel sets this + value internally but userspace needs to know this value to + determine if an event was caused by crossing this threshold. + iii) Messages create_thin <dev id> |