diff --git a/man/man5/zfs-events.5 b/man/man5/zfs-events.5 index 0d0e1a9593d5..846a7080d01c 100644 --- a/man/man5/zfs-events.5 +++ b/man/man5/zfs-events.5 @@ -1,965 +1,448 @@ -'\" te +.\" .\" Copyright (c) 2013 by Turbo Fredriksson . All rights reserved. .\" Portions Copyright 2018 by Richard Elling .\" The contents of this file are subject to the terms of the Common Development .\" and Distribution License (the "License"). You may not use this file except .\" in compliance with the License. You can obtain a copy of the license at .\" usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. .\" .\" See the License for the specific language governing permissions and .\" limitations under the License. When distributing Covered Code, include this .\" CDDL HEADER in each file and include the License file at .\" usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this .\" CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your .\" own identifying information: .\" Portions Copyright [yyyy] [name of copyright owner] -.TH ZFS-EVENTS 5 "Aug 24, 2020" OpenZFS -.SH NAME -zfs\-events \- Events created by the ZFS filesystem. -.SH DESCRIPTION -.sp -.LP +.\" +.Dd May 26, 2021 +.Dt ZFS-EVENTS 5 +.Os +. +.Sh NAME +.Nm zfs-events +.Nd Events created by the ZFS filesystem +.Sh DESCRIPTION Description of the different events generated by the ZFS stack. -.sp -Most of these don't have any description. The events generated by ZFS -have never been publicly documented. What is here is intended as a -starting point to provide documentation for all possible events. -.sp +.Pp +Most of these don't have any description. +The events generated by ZFS have never been publicly documented. +What is here is intended as a starting point to provide documentation +for all possible events. +.Pp To view all events created since the loading of the ZFS infrastructure (i.e, "the module"), run -.P -.nf -\fBzpool events\fR -.fi -.P +.Dl Nm zpool Cm events to get a short list, and -.P -.nf -\fBzpool events -v\fR -.fi -.P +.Dl Nm zpool Cm events Fl v to get a full detail of the events and what information is available about it. -.sp -This man page lists the different subclasses that are issued -in the case of an event. The full event name would be -\fIereport.fs.zfs.SUBCLASS\fR, but we only list the last -part here. - -.SS "EVENTS (SUBCLASS)" -.sp -.LP - -.sp -.ne 2 -.na -\fBchecksum\fR -.ad -.RS 12n +.Pp +This manual page lists the different subclasses that are issued +in the case of an event. +The full event name would be +.Sy ereport.fs.zfs.\& Ns Em SUBCLASS , +but we only list the last part here. +. +.Sh EVENTS (SUBCLASS) +.Bl -tag -compact -width "vdev.bad_guid_sum" +.It Sy checksum Issued when a checksum error has been detected. -.RE - -.sp -.ne 2 -.na -\fBio\fR -.ad -.RS 12n +.It Sy io Issued when there is an I/O error in a vdev in the pool. -.RE - -.sp -.ne 2 -.na -\fBdata\fR -.ad -.RS 12n +.It Sy data Issued when there have been data errors in the pool. -.RE - -.sp -.ne 2 -.na -\fBdeadman\fR -.ad -.RS 12n -Issued when an I/O is determined to be "hung", this can be caused by lost -completion events due to flaky hardware or drivers. See the -\fBzfs_deadman_failmode\fR module option description for additional -information regarding "hung" I/O detection and configuration. -.RE - -.sp -.ne 2 -.na -\fBdelay\fR -.ad -.RS 12n -Issued when a completed I/O exceeds the maximum allowed time specified -by the \fBzio_slow_io_ms\fR module option. This can be an indicator of -problems with the underlying storage device. The number of delay events is -ratelimited by the \fBzfs_slow_io_events_per_second\fR module parameter. -.RE - -.sp -.ne 2 -.na -\fBconfig.sync\fR -.ad -.RS 12n +.It Sy deadman +Issued when an I/O request is determined to be "hung", this can be caused +by lost completion events due to flaky hardware or drivers. +See +.Sy zfs_deadman_failmode +in +.Xr zfs-module-parameters 5 +for additional information regarding "hung" I/O detection and configuration. +.It Sy delay +Issued when a completed I/O request exceeds the maximum allowed time +specified by the +.Sy zio_slow_io_ms +module parameter. +This can be an indicator of problems with the underlying storage device. +The number of delay events is ratelimited by the +.Sy zfs_slow_io_events_per_second +module parameter. +.It Sy config Issued every time a vdev change have been done to the pool. -.RE - -.sp -.ne 2 -.na -\fBzpool\fR -.ad -.RS 12n +.It Sy zpool Issued when a pool cannot be imported. -.RE - -.sp -.ne 2 -.na -\fBzpool.destroy\fR -.ad -.RS 12n +.It Sy zpool.destroy Issued when a pool is destroyed. -.RE - -.sp -.ne 2 -.na -\fBzpool.export\fR -.ad -.RS 12n +.It Sy zpool.export Issued when a pool is exported. -.RE - -.sp -.ne 2 -.na -\fBzpool.import\fR -.ad -.RS 12n +.It Sy zpool.import Issued when a pool is imported. -.RE - -.sp -.ne 2 -.na -\fBzpool.reguid\fR -.ad -.RS 12n +.It Sy zpool.reguid Issued when a REGUID (new unique identifier for the pool have been regenerated) have been detected. -.RE - -.sp -.ne 2 -.na -\fBvdev.unknown\fR -.ad -.RS 12n -Issued when the vdev is unknown. Such as trying to clear device -errors on a vdev that have failed/been kicked from the system/pool -and is no longer available. -.RE - -.sp -.ne 2 -.na -\fBvdev.open_failed\fR -.ad -.RS 12n +.It Sy vdev.unknown +Issued when the vdev is unknown. +Such as trying to clear device errors on a vdev that have failed/been kicked +from the system/pool and is no longer available. +.It Sy vdev.open_failed Issued when a vdev could not be opened (because it didn't exist for example). -.RE - -.sp -.ne 2 -.na -\fBvdev.corrupt_data\fR -.ad -.RS 12n +.It Sy vdev.corrupt_data Issued when corrupt data have been detected on a vdev. -.RE - -.sp -.ne 2 -.na -\fBvdev.no_replicas\fR -.ad -.RS 12n +.It Sy vdev.no_replicas Issued when there are no more replicas to sustain the pool. -This would lead to the pool being \fIDEGRADED\fR. -.RE - -.sp -.ne 2 -.na -\fBvdev.bad_guid_sum\fR -.ad -.RS 12n +This would lead to the pool being +.Em DEGRADED . +.It Sy vdev.bad_guid_sum Issued when a missing device in the pool have been detected. -.RE - -.sp -.ne 2 -.na -\fBvdev.too_small\fR -.ad -.RS 12n +.It Sy vdev.too_small Issued when the system (kernel) have removed a device, and ZFS -notices that the device isn't there any more. This is usually -followed by a \fBprobe_failure\fR event. -.RE - -.sp -.ne 2 -.na -\fBvdev.bad_label\fR -.ad -.RS 12n +notices that the device isn't there any more. +This is usually followed by a +.Sy probe_failure +event. +.It Sy vdev.bad_label Issued when the label is OK but invalid. -.RE - -.sp -.ne 2 -.na -\fBvdev.bad_ashift\fR -.ad -.RS 12n +.It Sy vdev.bad_ashift Issued when the ashift alignment requirement has increased. -.RE - -.sp -.ne 2 -.na -\fBvdev.remove\fR -.ad -.RS 12n +.It Sy vdev.remove Issued when a vdev is detached from a mirror (or a spare detached from a vdev where it have been used to replace a failed drive - only works if the original drive have been readded). -.RE - -.sp -.ne 2 -.na -\fBvdev.clear\fR -.ad -.RS 12n -Issued when clearing device errors in a pool. Such as running \fBzpool clear\fR +.It Sy vdev.clear +Issued when clearing device errors in a pool. +Such as running +.Nm zpool Cm clear on a device in the pool. -.RE - -.sp -.ne 2 -.na -\fBvdev.check\fR -.ad -.RS 12n +.It Sy vdev.check Issued when a check to see if a given vdev could be opened is started. -.RE - -.sp -.ne 2 -.na -\fBvdev.spare\fR -.ad -.RS 12n +.It Sy vdev.spare Issued when a spare have kicked in to replace a failed device. -.RE - -.sp -.ne 2 -.na -\fBvdev.autoexpand\fR -.ad -.RS 12n +.It Sy vdev.autoexpand Issued when a vdev can be automatically expanded. -.RE - -.sp -.ne 2 -.na -\fBio_failure\fR -.ad -.RS 12n +.It Sy io_failure Issued when there is an I/O failure in a vdev in the pool. -.RE - -.sp -.ne 2 -.na -\fBprobe_failure\fR -.ad -.RS 12n -Issued when a probe fails on a vdev. This would occur if a vdev +.It Sy probe_failure +Issued when a probe fails on a vdev. +This would occur if a vdev have been kicked from the system outside of ZFS (such as the kernel have removed the device). -.RE - -.sp -.ne 2 -.na -\fBlog_replay\fR -.ad -.RS 12n -Issued when the intent log cannot be replayed. The can occur in the case -of a missing or damaged log device. -.RE - -.sp -.ne 2 -.na -\fBresilver.start\fR -.ad -.RS 12n +.It Sy log_replay +Issued when the intent log cannot be replayed. +The can occur in the case of a missing or damaged log device. +.It Sy resilver.start Issued when a resilver is started. -.RE - -.sp -.ne 2 -.na -\fBresilver.finish\fR -.ad -.RS 12n +.It Sy resilver.finish Issued when the running resilver have finished. -.RE - -.sp -.ne 2 -.na -\fBscrub.start\fR -.ad -.RS 12n +.It Sy scrub.start Issued when a scrub is started on a pool. -.RE - -.sp -.ne 2 -.na -\fBscrub.finish\fR -.ad -.RS 12n +.It Sy scrub.finish Issued when a pool has finished scrubbing. -.RE - -.sp -.ne 2 -.na -\fBscrub.abort\fR -.ad -.RS 12n +.It Sy scrub.abort Issued when a scrub is aborted on a pool. -.RE - -.sp -.ne 2 -.na -\fBscrub.resume\fR -.ad -.RS 12n +.It Sy scrub.resume Issued when a scrub is resumed on a pool. -.RE - -.sp -.ne 2 -.na -\fBscrub.paused\fR -.ad -.RS 12n +.It Sy scrub.paused Issued when a scrub is paused on a pool. -.RE - -.sp -.ne 2 -.na -\fBbootfs.vdev.attach\fR -.ad -.RS 12n -.RE - -.SS "PAYLOADS" -.sp -.LP +.It Sy bootfs.vdev.attach +.El +. +.Sh PAYLOADS This is the payload (data, information) that accompanies an event. -.sp +.Pp For -.BR zed (8), -these are set to uppercase and prefixed with \fBZEVENT_\fR. - -.sp -.ne 2 -.na -\fBpool\fR -.ad -.RS 12n +.Xr zed 8 , +these are set to uppercase and prefixed with +.Sy ZEVENT_ . +.Bl -tag -compact -width "vdev_cksum_errors" +.It Sy pool Pool name. -.RE - -.sp -.ne 2 -.na -\fBpool_failmode\fR -.ad -.RS 12n -Failmode - \fBwait\fR, \fBcontinue\fR or \fBpanic\fR. -See -.BR zpool (8) -(\fIfailmode\fR property) for more information. -.RE - -.sp -.ne 2 -.na -\fBpool_guid\fR -.ad -.RS 12n +.It Sy pool_failmode +Failmode - +.Sy wait , +.Sy continue , +or +.Sy panic . +See the +.Sy failmode +property in +.Xr zpoolprops 8 +for more information. +.It Sy pool_guid The GUID of the pool. -.RE - -.sp -.ne 2 -.na -\fBpool_context\fR -.ad -.RS 12n +.It Sy pool_context The load state for the pool (0=none, 1=open, 2=import, 3=tryimport, 4=recover 5=error). -.RE - -.sp -.ne 2 -.na -\fBvdev_guid\fR -.ad -.RS 12n +.It Sy vdev_guid The GUID of the vdev in question (the vdev failing or operated upon with -\fBzpool clear\fR etc). -.RE - -.sp -.ne 2 -.na -\fBvdev_type\fR -.ad -.RS 12n -Type of vdev - \fBdisk\fR, \fBfile\fR, \fBmirror\fR etc. See -.BR zpool (8) -under \fBVirtual Devices\fR for more information on possible values. -.RE - -.sp -.ne 2 -.na -\fBvdev_path\fR -.ad -.RS 12n -Full path of the vdev, including any \fI-partX\fR. -.RE - -.sp -.ne 2 -.na -\fBvdev_devid\fR -.ad -.RS 12n +.Nm zpool Cm clear , +etc.). +.It Sy vdev_type +Type of vdev - +.Sy disk , +.Sy file , +.Sy mirror , +etc. +See the +.Sy Virtual Devices +section of +.Xr zpoolconcepts 8 +for more information on possible values. +.It Sy vdev_path +Full path of the vdev, including any +.Em -partX . +.It Sy vdev_devid ID of vdev (if any). -.RE - -.sp -.ne 2 -.na -\fBvdev_fru\fR -.ad -.RS 12n +.It Sy vdev_fru Physical FRU location. -.RE - -.sp -.ne 2 -.na -\fBvdev_state\fR -.ad -.RS 12n +.It Sy vdev_state State of vdev (0=uninitialized, 1=closed, 2=offline, 3=removed, 4=failed to open, 5=faulted, 6=degraded, 7=healthy). -.RE - -.sp -.ne 2 -.na -\fBvdev_ashift\fR -.ad -.RS 12n +.It Sy vdev_ashift The ashift value of the vdev. -.RE - -.sp -.ne 2 -.na -\fBvdev_complete_ts\fR -.ad -.RS 12n -The time the last I/O completed for the specified vdev. -.RE - -.sp -.ne 2 -.na -\fBvdev_delta_ts\fR -.ad -.RS 12n -The time since the last I/O completed for the specified vdev. -.RE - -.sp -.ne 2 -.na -\fBvdev_spare_paths\fR -.ad -.RS 12n -List of spares, including full path and any \fI-partX\fR. -.RE - -.sp -.ne 2 -.na -\fBvdev_spare_guids\fR -.ad -.RS 12n +.It Sy vdev_complete_ts +The time the last I/O request completed for the specified vdev. +.It Sy vdev_delta_ts +The time since the last I/O request completed for the specified vdev. +.It Sy vdev_spare_paths +List of spares, including full path and any +.Em -partX . +.It Sy vdev_spare_guids GUID(s) of spares. -.RE - -.sp -.ne 2 -.na -\fBvdev_read_errors\fR -.ad -.RS 12n +.It Sy vdev_read_errors How many read errors that have been detected on the vdev. -.RE - -.sp -.ne 2 -.na -\fBvdev_write_errors\fR -.ad -.RS 12n +.It Sy vdev_write_errors How many write errors that have been detected on the vdev. -.RE - -.sp -.ne 2 -.na -\fBvdev_cksum_errors\fR -.ad -.RS 12n +.It Sy vdev_cksum_errors How many checksum errors that have been detected on the vdev. -.RE - -.sp -.ne 2 -.na -\fBparent_guid\fR -.ad -.RS 12n +.It Sy parent_guid GUID of the vdev parent. -.RE - -.sp -.ne 2 -.na -\fBparent_type\fR -.ad -.RS 12n -Type of parent. See \fBvdev_type\fR. -.RE - -.sp -.ne 2 -.na -\fBparent_path\fR -.ad -.RS 12n +.It Sy parent_type +Type of parent. +See +.Sy vdev_type . +.It Sy parent_path Path of the vdev parent (if any). -.RE - -.sp -.ne 2 -.na -\fBparent_devid\fR -.ad -.RS 12n +.It Sy parent_devid ID of the vdev parent (if any). -.RE - -.sp -.ne 2 -.na -\fBzio_objset\fR -.ad -.RS 12n -The object set number for a given I/O. -.RE - -.sp -.ne 2 -.na -\fBzio_object\fR -.ad -.RS 12n -The object number for a given I/O. -.RE - -.sp -.ne 2 -.na -\fBzio_level\fR -.ad -.RS 12n -The indirect level for the block. Level 0 is the lowest level and includes -data blocks. Values > 0 indicate metadata blocks at the appropriate level. -.RE - -.sp -.ne 2 -.na -\fBzio_blkid\fR -.ad -.RS 12n -The block ID for a given I/O. -.RE - -.sp -.ne 2 -.na -\fBzio_err\fR -.ad -.RS 12n -The errno for a failure when handling a given I/O. The errno is compatible -with \fBerrno\fR(3) with the value for EBADE (0x34) used to indicate ZFS -checksum error. -.RE - -.sp -.ne 2 -.na -\fBzio_offset\fR -.ad -.RS 12n -The offset in bytes of where to write the I/O for the specified vdev. -.RE - -.sp -.ne 2 -.na -\fBzio_size\fR -.ad -.RS 12n -The size in bytes of the I/O. -.RE - -.sp -.ne 2 -.na -\fBzio_flags\fR -.ad -.RS 12n -The current flags describing how the I/O should be handled. See the -\fBI/O FLAGS\fR section for the full list of I/O flags. -.RE - -.sp -.ne 2 -.na -\fBzio_stage\fR -.ad -.RS 12n -The current stage of the I/O in the pipeline. See the \fBI/O STAGES\fR +.It Sy zio_objset +The object set number for a given I/O request. +.It Sy zio_object +The object number for a given I/O request. +.It Sy zio_level +The indirect level for the block. +Level 0 is the lowest level and includes data blocks. +Values > 0 indicate metadata blocks at the appropriate level. +.It Sy zio_blkid +The block ID for a given I/O request. +.It Sy zio_err +The error number for a failure when handling a given I/O request, +compatible with +.Xr errno 3 +with the value of +.Sy EBADE +used to indicate a ZFS checksum error. +.It Sy zio_offset +The offset in bytes of where to write the I/O request for the specified vdev. +.It Sy zio_size +The size in bytes of the I/O request. +.It Sy zio_flags +The current flags describing how the I/O request should be handled. +See the +.Sy I/O FLAGS +section for the full list of I/O flags. +.It Sy zio_stage +The current stage of the I/O in the pipeline. +See the +.Sy I/O STAGES section for a full list of all the I/O stages. -.RE - -.sp -.ne 2 -.na -\fBzio_pipeline\fR -.ad -.RS 12n -The valid pipeline stages for the I/O. See the \fBI/O STAGES\fR section for a -full list of all the I/O stages. -.RE - -.sp -.ne 2 -.na -\fBzio_delay\fR -.ad -.RS 12n +.It Sy zio_pipeline +The valid pipeline stages for the I/O. +See the +.Sy I/O STAGES +section for a full list of all the I/O stages. +.It Sy zio_delay The time elapsed (in nanoseconds) waiting for the block layer to complete the -I/O. Unlike \fBzio_delta\fR this does not include any vdev queuing time and is +I/O request. +Unlike +.Sy zio_delta , +this does not include any vdev queuing time and is therefore solely a measure of the block layer performance. -.RE - -.sp -.ne 2 -.na -\fBzio_timestamp\fR -.ad -.RS 12n -The time when a given I/O was submitted. -.RE - -.sp -.ne 2 -.na -\fBzio_delta\fR -.ad -.RS 12n -The time required to service a given I/O. -.RE - -.sp -.ne 2 -.na -\fBprev_state\fR -.ad -.RS 12n +.It Sy zio_timestamp +The time when a given I/O request was submitted. +.It Sy zio_delta +The time required to service a given I/O request. +.It Sy prev_state The previous state of the vdev. -.RE - -.sp -.ne 2 -.na -\fBcksum_expected\fR -.ad -.RS 12n +.It Sy cksum_expected The expected checksum value for the block. -.RE - -.sp -.ne 2 -.na -\fBcksum_actual\fR -.ad -.RS 12n +.It Sy cksum_actual The actual checksum value for an errant block. -.RE - -.sp -.ne 2 -.na -\fBcksum_algorithm\fR -.ad -.RS 12n -Checksum algorithm used. See \fBzfs\fR(8) for more information on checksum -algorithms available. -.RE - -.sp -.ne 2 -.na -\fBcksum_byteswap\fR -.ad -.RS 12n +.It Sy cksum_algorithm +Checksum algorithm used. +See +.Xr zfsprops 8 +for more information on the available checksum algorithms. +.It Sy cksum_byteswap Whether or not the data is byteswapped. -.RE - -.sp -.ne 2 -.na -\fBbad_ranges\fR -.ad -.RS 12n -[start, end) pairs of corruption offsets. Offsets are always aligned on a -64-bit boundary, and can include some gaps of non-corruption. -(See \fBbad_ranges_min_gap\fR) -.RE - -.sp -.ne 2 -.na -\fBbad_ranges_min_gap\fR -.ad -.RS 12n -In order to bound the size of the \fBbad_ranges\fR array, gaps of non-corruption -less than or equal to \fBbad_ranges_min_gap\fR bytes have been merged with -adjacent corruption. Always at least 8 bytes, since corruption is detected -on a 64-bit word basis. -.RE - -.sp -.ne 2 -.na -\fBbad_range_sets\fR -.ad -.RS 12n -This array has one element per range in \fBbad_ranges\fR. Each element contains +.It Sy bad_ranges +.No [\& Ns Ar start , end ) +pairs of corruption offsets. +Offsets are always aligned on a 64-bit boundary, +and can include some gaps of non-corruption. +(See +.Sy bad_ranges_min_gap ) +.It Sy bad_ranges_min_gap +In order to bound the size of the +.Sy bad_ranges +array, gaps of non-corruption +less than or equal to +.Sy bad_ranges_min_gap +bytes have been merged with +adjacent corruption. +Always at least 8 bytes, since corruption is detected on a 64-bit word basis. +.It Sy bad_range_sets +This array has one element per range in +.Sy bad_ranges . +Each element contains the count of bits in that range which were clear in the good data and set in the bad data. -.RE - -.sp -.ne 2 -.na -\fBbad_range_clears\fR -.ad -.RS 12n -This array has one element per range in \fBbad_ranges\fR. Each element contains +.It Sy bad_range_clears +This array has one element per range in +.Sy bad_ranges . +Each element contains the count of bits for that range which were set in the good data and clear in the bad data. -.RE - -.sp -.ne 2 -.na -\fBbad_set_bits\fR -.ad -.RS 12n -If this field exists, it is an array of: (bad data & ~(good data)); that is, -the bits set in the bad data which are cleared in the good data. Each element -corresponds a byte whose offset is in a range in \fBbad_ranges\fR, and the -array is ordered by offset. Thus, the first element is the first byte in the -first \fBbad_ranges\fR range, and the last element is the last byte in the last -\fBbad_ranges\fR range. -.RE - -.sp -.ne 2 -.na -\fBbad_cleared_bits\fR -.ad -.RS 12n -Like \fBbad_set_bits\fR, but contains: (good data & ~(bad data)); that is, -the bits set in the good data which are cleared in the bad data. -.RE - -.sp -.ne 2 -.na -\fBbad_set_histogram\fR -.ad -.RS 12n -If this field exists, it is an array of counters. Each entry counts bits set -in a particular bit of a big-endian uint64 type. The first entry counts bits +.It Sy bad_set_bits +If this field exists, it is an array of +.Pq Ar bad data No & ~( Ns Ar good data ) ; +that is, the bits set in the bad data which are cleared in the good data. +Each element corresponds a byte whose offset is in a range in +.Sy bad_ranges , +and the array is ordered by offset. +Thus, the first element is the first byte in the first +.Sy bad_ranges +range, and the last element is the last byte in the last +.Sy bad_ranges +range. +.It Sy bad_cleared_bits +Like +.Sy bad_set_bits , +but contains +.Pq Ar good data No & ~( Ns Ar bad data ) ; +that is, the bits set in the good data which are cleared in the bad data. +.It Sy bad_set_histogram +If this field exists, it is an array of counters. +Each entry counts bits set in a particular bit of a big-endian uint64 type. +The first entry counts bits set in the high-order bit of the first byte, the 9th byte, etc, and the last entry counts bits set of the low-order bit of the 8th byte, the 16th byte, etc. This information is useful for observing a stuck bit in a parallel data path, such as IDE or parallel SCSI. -.RE - -.sp -.ne 2 -.na -\fBbad_cleared_histogram\fR -.ad -.RS 12n -If this field exists, it is an array of counters. Each entry counts bit clears -in a particular bit of a big-endian uint64 type. The first entry counts bits +.It Sy bad_cleared_histogram +If this field exists, it is an array of counters. +Each entry counts bit clears in a particular bit of a big-endian uint64 type. +The first entry counts bits clears of the high-order bit of the first byte, the 9th byte, etc, and the -last entry counts clears of the low-order bit of the 8th byte, the 16th byte, -etc. This information is useful for observing a stuck bit in a parallel data +last entry counts clears of the low-order bit of the 8th byte, the 16th byte, etc. +This information is useful for observing a stuck bit in a parallel data path, such as IDE or parallel SCSI. -.RE - -.SS "I/O STAGES" -.sp -.LP -The ZFS I/O pipeline is comprised of various stages which are defined -below. The individual stages are used to construct these basic I/O -operations: Read, Write, Free, Claim, and Ioctl. These stages may be -set on an event to describe the life cycle of a given I/O. - +.El +. +.Sh I/O STAGES +The ZFS I/O pipeline is comprised of various stages which are defined below. +The individual stages are used to construct these basic I/O +operations: Read, Write, Free, Claim, and Ioctl. +These stages may be +set on an event to describe the life cycle of a given I/O request. +.Pp .TS tab(:); l l l . Stage:Bit Mask:Operations _:_:_ ZIO_STAGE_OPEN:0x00000001:RWFCI ZIO_STAGE_READ_BP_INIT:0x00000002:R---- ZIO_STAGE_WRITE_BP_INIT:0x00000004:-W--- ZIO_STAGE_FREE_BP_INIT:0x00000008:--F-- ZIO_STAGE_ISSUE_ASYNC:0x00000010:RWF-- ZIO_STAGE_WRITE_COMPRESS:0x00000020:-W--- ZIO_STAGE_ENCRYPT:0x00000040:-W--- ZIO_STAGE_CHECKSUM_GENERATE:0x00000080:-W--- ZIO_STAGE_NOP_WRITE:0x00000100:-W--- ZIO_STAGE_DDT_READ_START:0x00000200:R---- ZIO_STAGE_DDT_READ_DONE:0x00000400:R---- ZIO_STAGE_DDT_WRITE:0x00000800:-W--- ZIO_STAGE_DDT_FREE:0x00001000:--F-- ZIO_STAGE_GANG_ASSEMBLE:0x00002000:RWFC- ZIO_STAGE_GANG_ISSUE:0x00004000:RWFC- ZIO_STAGE_DVA_THROTTLE:0x00008000:-W--- ZIO_STAGE_DVA_ALLOCATE:0x00010000:-W--- ZIO_STAGE_DVA_FREE:0x00020000:--F-- ZIO_STAGE_DVA_CLAIM:0x00040000:---C- ZIO_STAGE_READY:0x00080000:RWFCI ZIO_STAGE_VDEV_IO_START:0x00100000:RW--I ZIO_STAGE_VDEV_IO_DONE:0x00200000:RW--I ZIO_STAGE_VDEV_IO_ASSESS:0x00400000:RW--I ZIO_STAGE_CHECKSUM_VERIFY:0x00800000:R---- ZIO_STAGE_DONE:0x01000000:RWFCI .TE - -.SS "I/O FLAGS" -.sp -.LP -Every I/O in the pipeline contains a set of flags which describe its -function and are used to govern its behavior. These flags will be set -in an event as an \fBzio_flags\fR payload entry. - +. +.Sh I/O FLAGS +Every I/O request in the pipeline contains a set of flags which describe its +function and are used to govern its behavior. +These flags will be set in an event as a +.Sy zio_flags +payload entry. +.Pp .TS tab(:); l l . Flag:Bit Mask _:_ ZIO_FLAG_DONT_AGGREGATE:0x00000001 ZIO_FLAG_IO_REPAIR:0x00000002 ZIO_FLAG_SELF_HEAL:0x00000004 ZIO_FLAG_RESILVER:0x00000008 ZIO_FLAG_SCRUB:0x00000010 ZIO_FLAG_SCAN_THREAD:0x00000020 ZIO_FLAG_PHYSICAL:0x00000040 ZIO_FLAG_CANFAIL:0x00000080 ZIO_FLAG_SPECULATIVE:0x00000100 ZIO_FLAG_CONFIG_WRITER:0x00000200 ZIO_FLAG_DONT_RETRY:0x00000400 ZIO_FLAG_DONT_CACHE:0x00000800 ZIO_FLAG_NODATA:0x00001000 ZIO_FLAG_INDUCE_DAMAGE:0x00002000 ZIO_FLAG_IO_ALLOCATING:0x00004000 ZIO_FLAG_IO_RETRY:0x00008000 ZIO_FLAG_PROBE:0x00010000 ZIO_FLAG_TRYHARD:0x00020000 ZIO_FLAG_OPTIONAL:0x00040000 ZIO_FLAG_DONT_QUEUE:0x00080000 ZIO_FLAG_DONT_PROPAGATE:0x00100000 ZIO_FLAG_IO_BYPASS:0x00200000 ZIO_FLAG_IO_REWRITE:0x00400000 ZIO_FLAG_RAW_COMPRESS:0x00800000 ZIO_FLAG_RAW_ENCRYPT:0x01000000 ZIO_FLAG_GANG_CHILD:0x02000000 ZIO_FLAG_DDT_CHILD:0x04000000 ZIO_FLAG_GODFATHER:0x08000000 ZIO_FLAG_NOPWRITE:0x10000000 ZIO_FLAG_REEXECUTED:0x20000000 ZIO_FLAG_DELEGATED:0x40000000 ZIO_FLAG_FASTWRITE:0x80000000 .TE