fix wiki-special link to "USB installation"

[pve-docs.git] / pveceph.adoc

diff --git a/pveceph.adoc b/pveceph.adoc
index ef257acf945f76a552c42457398ade02a2745ad1..8dc85680ded076094afd9d7afb724f5ccd1761e7 100644 (file)
--- a/pveceph.adoc
+++ b/pveceph.adoc
@@ -18,8 +18,8 @@ DESCRIPTION
 -----------
 endif::manvolnum[]
 ifndef::manvolnum[]
 -----------
 endif::manvolnum[]
 ifndef::manvolnum[]

-Manage Ceph Services on Proxmox VE Nodes
-========================================
+Deploy Hyper-Converged Ceph Cluster
+===================================

 :pve-toplevel:
 endif::manvolnum[]
 
 :pve-toplevel:
 endif::manvolnum[]
 


@@ -86,9 +86,16 @@ provide enough resources for stable and durable Ceph performance.
 .Memory
 Especially in a hyper-converged setup, the memory consumption needs to be
 carefully monitored. In addition to the intended workload from virtual machines
 .Memory
 Especially in a hyper-converged setup, the memory consumption needs to be
 carefully monitored. In addition to the intended workload from virtual machines

-and container, Ceph needs enough memory available to provide good and stable
-performance. As a rule of thumb, for roughly 1 TiB of data, 1 GiB of memory
-will be used by an OSD. OSD caching will use additional memory.
+and containers, Ceph needs enough memory available to provide excellent and
+stable performance.
+
+As a rule of thumb, for roughly **1 TiB of data, 1 GiB of memory** will be used
+by an OSD. Especially during recovery, rebalancing or backfilling.
+
+The daemon itself will use additional memory. The Bluestore backend of the
+daemon requires by default **3-5 GiB of memory** (adjustable). In contrast, the
+legacy Filestore backend uses the OS page cache and the memory consumption is
+generally related to PGs of an OSD daemon.

 
 .Network
 We recommend a network bandwidth of at least 10 GbE or more, which is used
 
 .Network
 We recommend a network bandwidth of at least 10 GbE or more, which is used


@@ -101,7 +108,7 @@ services on the same network and may even break the {pve} cluster stack.
 
 Further, estimate your bandwidth needs. While one HDD might not saturate a 1 Gb
 link, multiple HDD OSDs per node can, and modern NVMe SSDs will even saturate
 
 Further, estimate your bandwidth needs. While one HDD might not saturate a 1 Gb
 link, multiple HDD OSDs per node can, and modern NVMe SSDs will even saturate

-10 Gbps of bandwidth quickly. Deploying a network capable of even more bandwith
+10 Gbps of bandwidth quickly. Deploying a network capable of even more bandwidth

 will ensure that it isn't your bottleneck and won't be anytime soon, 25, 40 or
 even 100 GBps are possible.
 
 will ensure that it isn't your bottleneck and won't be anytime soon, 25, 40 or
 even 100 GBps are possible.
 


@@ -286,7 +293,7 @@ monitor the cluster. Since the Ceph luminous release at least one ceph-mgr
 footnote:[Ceph Manager https://docs.ceph.com/docs/{ceph_codename}/mgr/] daemon is
 required.
 
 footnote:[Ceph Manager https://docs.ceph.com/docs/{ceph_codename}/mgr/] daemon is
 required.
 

-[i[pveceph_create_mgr]]
+[[pveceph_create_mgr]]

 Create Manager
 ~~~~~~~~~~~~~~
 
 Create Manager
 ~~~~~~~~~~~~~~
 


@@ -378,7 +385,7 @@ pveceph osd create /dev/sd[X] -db_dev /dev/sd[Y] -wal_dev /dev/sd[Z]
 ----
 
 You can directly choose the size for those with the '-db_size' and '-wal_size'
 ----
 
 You can directly choose the size for those with the '-db_size' and '-wal_size'

-paremeters respectively. If they are not given the following values (in order)
+parameters respectively. If they are not given the following values (in order)

 will be used:
 
 * bluestore_block_{db,wal}_size from ceph configuration...
 will be used:
 
 * bluestore_block_{db,wal}_size from ceph configuration...


@@ -762,9 +769,9 @@ Trim/Discard
 ~~~~~~~~~~~~
 It is a good measure to run 'fstrim' (discard) regularly on VMs or containers.
 This releases data blocks that the filesystem isn’t using anymore. It reduces
 ~~~~~~~~~~~~
 It is a good measure to run 'fstrim' (discard) regularly on VMs or containers.
 This releases data blocks that the filesystem isn’t using anymore. It reduces

-data usage and the resource load. Most modern operating systems issue such
-discard commands to their disks regurarly. You only need to ensure that the
-Virtual Machines enable the xref:qm_hard_disk_discard[disk discard option].
+data usage and resource load. Most modern operating systems issue such discard
+commands to their disks regularly. You only need to ensure that the Virtual
+Machines enable the xref:qm_hard_disk_discard[disk discard option].

 
 [[pveceph_scrub]]
 Scrub & Deep Scrub
 
 [[pveceph_scrub]]
 Scrub & Deep Scrub