From feb3a7eef114b6d23bc1aaf5c550b2abeffaca94 Mon Sep 17 00:00:00 2001 From: George Amanakis Date: Tue, 8 Sep 2020 14:44:37 -0400 Subject: Introduce ZFS module parameter l2arc_mfuonly In certain workloads it may be beneficial to reduce wear of L2ARC devices by not caching MRU metadata and data into L2ARC. This commit introduces a new tunable l2arc_mfuonly for this purpose. Reviewed-by: Matthew Ahrens Reviewed-by: Richard Elling Reviewed-by: Brian Behlendorf Signed-off-by: George Amanakis Closes #10710 --- man/man5/zfs-module-parameters.5 | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) (limited to 'man') diff --git a/man/man5/zfs-module-parameters.5 b/man/man5/zfs-module-parameters.5 index 32e28a13a..41f693a03 100644 --- a/man/man5/zfs-module-parameters.5 +++ b/man/man5/zfs-module-parameters.5 @@ -198,6 +198,22 @@ feature. Default value: \fB200\fR%. .RE +.sp +.ne 2 +.na +\fBl2arc_mfuonly\fR (int) +.ad +.RS 12n +Controls whether only MFU metadata and data are cached from ARC into L2ARC. +This may be desired to avoid wasting space on L2ARC when reading/writing large +amounts of data that are not expected to be accessed more than once. The +default is \fB0\fR, meaning both MRU and MFU data and metadata are cached. +When turning off (\fB0\fR) this feature some MRU buffers will still be present +in ARC and eventually cached on L2ARC. +.sp +Use \fB0\fR for no (default) and \fB1\fR for yes. +.RE + .sp .ne 2 .na -- cgit v1.2.3