Change checksum & IO delay ratelimit values

Change checksum & IO delay ratelimit thresholds from 5/sec to 20/sec.
This allows zed to actually trigger if a bunch of these events arrive in
a short period of time (zed has a threshold of 10 events in 10 sec).
Previously, if you had, say, 100 checksum errors in 1 sec, it would get
ratelimited to 5/sec which wouldn't trigger zed to fault the drive.

Also, convert the checksum and IO delay thresholds to module params for
easy testing.

Reviewed-by: loli10K <[email protected]>
Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: Giuseppe Di Natale <[email protected]>
Signed-off-by: Tony Hutter <[email protected]>
Closes #7252 

1 files changed, 24 insertions, 0 deletions

diff --git a/man/man5/zfs-module-parameters.5 b/man/man5/zfs-module-parameters.5
index 17335ebed..b7d32e069 100644
--- a/man/man5/zfs-module-parameters.5
+++ b/man/man5/zfs-module-parameters.5
@@ -756,6 +756,19 @@ Use \fB1\fR for yes (default) and \fB0\fR for no.
 .sp
 .ne 2
 .na
+\fBzfs_checksums_per_second\fR (int)
+.ad
+.RS 12n
+Rate limit checksum events to this many per second.  Note that this should
+not be set below the zed thresholds (currently 10 checksums over 10 sec)
+or else zed may not trigger any action.
+.sp
+Default value: 20
+.RE
+
+.sp
+.ne 2
+.na
 \fBzfs_commit_timeout_pct\fR (int)
 .ad
 .RS 12n
@@ -932,6 +945,17 @@ Default value: \fB500,000\fR.
 .sp
 .ne 2
 .na
+\fBzfs_delays_per_second\fR (int)
+.ad
+.RS 12n
+Rate limit IO delay events to this many per second.
+.sp
+Default value: 20
+.RE
+
+.sp
+.ne 2
+.na
 \fBzfs_delete_blocks\fR (ulong)
 .ad
 .RS 12n