diff options
Diffstat (limited to 'man/man5/zfs-module-parameters.5')
| -rw-r--r-- | man/man5/zfs-module-parameters.5 | 64 |
1 files changed, 49 insertions, 15 deletions
diff --git a/man/man5/zfs-module-parameters.5 b/man/man5/zfs-module-parameters.5 index 5b7a29d32..039e024bb 100644 --- a/man/man5/zfs-module-parameters.5 +++ b/man/man5/zfs-module-parameters.5 @@ -823,14 +823,36 @@ Default value: \fB0\fR. .ad .RS 12n When a pool sync operation takes longer than \fBzfs_deadman_synctime_ms\fR -milliseconds, a "slow spa_sync" message is logged to the debug log -(see \fBzfs_dbgmsg_enable\fR). If \fBzfs_deadman_enabled\fR is set, -all pending IO operations are also checked and if any haven't completed -within \fBzfs_deadman_synctime_ms\fR milliseconds, a "SLOW IO" message -is logged to the debug log and a "delay" system event with the details of -the hung IO is posted. +milliseconds, or when an individual I/O takes longer than +\fBzfs_deadman_ziotime_ms\fR milliseconds, then the operation is considered to +be "hung". If \fBzfs_deadman_enabled\fR is set then the deadman behavior is +invoked as described by the \fBzfs_deadman_failmode\fR module option. +By default the deadman is enabled and configured to \fBwait\fR which results +in "hung" I/Os only being logged. The deadman is automatically disabled +when a pool gets suspended. .sp -Use \fB1\fR (default) to enable the slow IO check and \fB0\fR to disable. +Default value: \fB1\fR. +.RE + +.sp +.ne 2 +.na +\fBzfs_deadman_failmode\fR (charp) +.ad +.RS 12n +Controls the failure behavior when the deadman detects a "hung" I/O. Valid +values are \fBwait\fR, \fBcontinue\fR, and \fBpanic\fR. +.sp +\fBwait\fR - Wait for a "hung" I/O to complete. For each "hung" I/O a +"deadman" event will be posted describing that I/O. +.sp +\fBcontinue\fR - Attempt to recover from a "hung" I/O by re-dispatching it +to the I/O pipeline if possible. +.sp +\fBpanic\fR - Panic the system. This can be used to facilitate an automatic +fail-over to a properly configured fail-over partner. +.sp +Default value: \fBwait\fR. .RE .sp @@ -839,11 +861,10 @@ Use \fB1\fR (default) to enable the slow IO check and \fB0\fR to disable. \fBzfs_deadman_checktime_ms\fR (int) .ad .RS 12n -Once a pool sync operation has taken longer than -\fBzfs_deadman_synctime_ms\fR milliseconds, continue to check for slow -operations every \fBzfs_deadman_checktime_ms\fR milliseconds. +Check time in milliseconds. This defines the frequency at which we check +for hung I/O and potentially invoke the \fBzfs_deadman_failmode\fR behavior. .sp -Default value: \fB5,000\fR. +Default value: \fB60,000\fR. .RE .sp @@ -853,12 +874,25 @@ Default value: \fB5,000\fR. .ad .RS 12n Interval in milliseconds after which the deadman is triggered and also -the interval after which an IO operation is considered to be "hung" -if \fBzfs_deadman_enabled\fR is set. +the interval after which a pool sync operation is considered to be "hung". +Once this limit is exceeded the deadman will be invoked every +\fBzfs_deadman_checktime_ms\fR milliseconds until the pool sync completes. +.sp +Default value: \fB600,000\fR. +.RE -See \fBzfs_deadman_enabled\fR. .sp -Default value: \fB1,000,000\fR. +.ne 2 +.na +\fBzfs_deadman_ziotime_ms\fR (ulong) +.ad +.RS 12n +Interval in milliseconds after which the deadman is triggered and an +individual IO operation is considered to be "hung". As long as the I/O +remains "hung" the deadman will be invoked every \fBzfs_deadman_checktime_ms\fR +milliseconds until the I/O completes. +.sp +Default value: \fB300,000\fR. .RE .sp |