From cdefd8635de24200b55822fa0b6bc23a638fb87a Mon Sep 17 00:00:00 2001

From: David Teigland <teigland@redhat.com>

Date: Mon, 21 Feb 2022 11:35:58 -0600

Subject: [PATCH 33/54] man lvmcache: mention writecache memory usage

---

 man/lvmcache.7_main | 12 ++++++++++++

 1 file changed, 12 insertions(+)

diff --git a/man/lvmcache.7_main b/man/lvmcache.7_main

index 48cf7b492..73680235b 100644

--- a/man/lvmcache.7_main

+++ b/man/lvmcache.7_main

@@ -240,6 +240,18 @@ The writecache block size should be chosen to match the xfs sectsz value.

 It is also possible to specify a sector size of 4096 to mkfs.xfs when

 creating the file system.  In this case the writecache block size of 4096

 can be used.

+.P

+.SS dm-writecache memory usage

+.P

+The amount of main system memory used by dm-writecache can be a factor

+when selecting the writecache cachevol size and the writecache block size.

+.P

+.IP \[bu] 2

+writecache block size 4096: each 100 GiB of writecache cachevol uses

+slighly over 2 GiB of system memory.

+.IP \[bu] 2

+writecache block size 512: each 100 GiB of writecache cachevol uses

+a little over 16 GiB of system memory.

 .

 .SS dm-writecache settings

 .

-- 

2.34.3