From 073bd3092c4a0aa81bd0be7a0333c25efbbaec83 Mon Sep 17 00:00:00 2001 From: Matty Williams Date: Mon, 23 Feb 2026 16:32:13 +0000 Subject: [PATCH] doc: Update documentation to reflect new functionality https://tracker.ceph.com/issues/74188 Signed-off-by: Matty Williams --- doc/glossary.rst | 5 ++++- doc/rados/operations/erasure-code.rst | 12 ++++++------ doc/rados/operations/pools.rst | 5 +++++ 3 files changed, 15 insertions(+), 7 deletions(-) diff --git a/doc/glossary.rst b/doc/glossary.rst index 66b8a9299d25..0df78710717e 100644 --- a/doc/glossary.rst +++ b/doc/glossary.rst @@ -352,7 +352,10 @@ "object map". A key-value store (a database) that is used to reduce the time it takes to read data from and to write to the Ceph cluster. RGW bucket indexes are stored as omaps. - Erasure-coded pools cannot store RADOS omap data structures. + Erasure-coded pools, by default, cannot store RADOS omap data + structures. This functionality can be enabled in erasure-coded + pools with optimizations enabled by setting the + ``supports_omap`` flag to true. Run the command ``ceph osd df`` to see the storage space used by omaps on each OSD. diff --git a/doc/rados/operations/erasure-code.rst b/doc/rados/operations/erasure-code.rst index 5b6af231da1f..eae3427ee44d 100644 --- a/doc/rados/operations/erasure-code.rst +++ b/doc/rados/operations/erasure-code.rst @@ -197,9 +197,9 @@ should be migrated to BlueStore. There is no downside to enabling EC overwrites, so it is best practice to routinely do so. -Erasure-coded pools do not support omap, so to use them with RBD and -CephFS you must instruct them and their clients to store their data in an EC pool and -their metadata in a replicated pool. For RBD, this means using the +RBD and CephFS are not fully supported in erasure-coded pools, instead +you must instruct them and their clients to store their data in an EC +pool and their metadata in a replicated pool. For RBD, this means using the erasure-coded pool as the ``--data-pool`` during image creation: .. prompt:: bash $ @@ -500,9 +500,9 @@ Erasure-coded pools and cache tiering .. note:: Cache tiering was deprecated in Reef. We strongly advise not deploying new cache tiers, and working to remove them from existing deployments. Erasure-coded pools require more resources than replicated pools and -lack some of the functionality supported by replicated pools (for example, omap). -To overcome these limitations, one can set up a `cache tier <../cache-tiering>`_ -before setting up the erasure-coded pool. +lack some of the functionality supported by replicated pools (for example, omap +is not supported by default). To overcome these limitations, one can set up a +`cache tier <../cache-tiering>`_ before setting up the erasure-coded pool. For example, if the pool *hot-storage* is made of fast storage, the following commands will place the *hot-storage* pool as a tier of *ecpool* in *writeback* diff --git a/doc/rados/operations/pools.rst b/doc/rados/operations/pools.rst index 1d79f264ec0d..dca87534d232 100644 --- a/doc/rados/operations/pools.rst +++ b/doc/rados/operations/pools.rst @@ -459,6 +459,11 @@ You may set values for the following keys: .. versionadded:: 20.2.0 +.. describe:: supports_omap + + :Description: Determines whether omap operations can be performed on a pool. On by default for replicated pools, off by default for erasure coded pools. The flag can be enabled for erasure coded pools that allow ec optimizations. + :Type: Boolean + .. describe:: hashpspool :Description: Sets or unsets the ``HASHPSPOOL`` flag on a given pool. -- 2.47.3