From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Teigland Date: Mon, 21 Feb 2022 17:36:31 +0000 (GMT) Subject: main - man lvmcache: mention writecache memory usage Message-ID: <20220221173631.21232385DC22@sourceware.org> List-Id: To: lvm-devel@redhat.com MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Gitweb: https://sourceware.org/git/?p=lvm2.git;a=commitdiff;h=6144dac897728a4857294d70645df8ed7a5ff11f Commit: 6144dac897728a4857294d70645df8ed7a5ff11f Parent: 96c99d647ef783abcd26a1f3f63f12e033195633 Author: David Teigland AuthorDate: Mon Feb 21 11:35:58 2022 -0600 Committer: David Teigland CommitterDate: Mon Feb 21 11:35:58 2022 -0600 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 dddd33cfa..ce440bf49 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 .