.\" Copyright (c) 2013 by Turbo Fredriksson <turbo@bayour.com>. All rights reserved.
.\" Copyright (c) 2019, 2021 by Delphix. All rights reserved.
.\" Copyright (c) 2019 Datto Inc.
+.\" Copyright (c) 2023, 2024 Klara, Inc.
.\" 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
.\" own identifying information:
.\" Portions Copyright [yyyy] [name of copyright owner]
.\"
-.Dd July 21, 2023
+.Dd January 9, 2024
.Dt ZFS 4
.Os
.
.It Sy l2arc_feed_secs Ns = Ns Sy 1 Pq u64
Seconds between L2ARC writing.
.
-.It Sy l2arc_headroom Ns = Ns Sy 2 Pq u64
+.It Sy l2arc_headroom Ns = Ns Sy 8 Pq u64
How far through the ARC lists to search for L2ARC cacheable content,
expressed as a multiplier of
.Sy l2arc_write_max .
.It Sy l2arc_norw Ns = Ns Sy 0 Ns | Ns 1 Pq int
No reads during writes.
.
-.It Sy l2arc_write_boost Ns = Ns Sy 8388608 Ns B Po 8 MiB Pc Pq u64
+.It Sy l2arc_write_boost Ns = Ns Sy 33554432 Ns B Po 32 MiB Pc Pq u64
Cold L2ARC devices will have
.Sy l2arc_write_max
increased by this amount while they remain cold.
.
-.It Sy l2arc_write_max Ns = Ns Sy 8388608 Ns B Po 8 MiB Pc Pq u64
+.It Sy l2arc_write_max Ns = Ns Sy 33554432 Ns B Po 32 MiB Pc Pq u64
Max write bytes per interval.
.
.It Sy l2arc_rebuild_enabled Ns = Ns Sy 1 Ns | Ns 0 Pq int
.Sy metaslab_force_ganging ) ,
force this many of them to be gang blocks.
.
-.It Sy zfs_ddt_zap_default_bs Ns = Ns Sy 15 Po 32 KiB Pc Pq int
+.It Sy brt_zap_prefetch Ns = Ns Sy 1 Ns | Ns 0 Pq int
+Controls prefetching BRT records for blocks which are going to be cloned.
+.
+.It Sy brt_zap_default_bs Ns = Ns Sy 12 Po 4 KiB Pc Pq int
+Default BRT ZAP data block size as a power of 2. Note that changing this after
+creating a BRT on the pool will not affect existing BRTs, only newly created
+ones.
+.
+.It Sy brt_zap_default_ibs Ns = Ns Sy 12 Po 4 KiB Pc Pq int
+Default BRT ZAP indirect block size as a power of 2. Note that changing this
+after creating a BRT on the pool will not affect existing BRTs, only newly
+created ones.
+.
+.It Sy ddt_zap_default_bs Ns = Ns Sy 15 Po 32 KiB Pc Pq int
Default DDT ZAP data block size as a power of 2. Note that changing this after
creating a DDT on the pool will not affect existing DDTs, only newly created
ones.
.
-.It Sy zfs_ddt_zap_default_ibs Ns = Ns Sy 15 Po 32 KiB Pc Pq int
+.It Sy ddt_zap_default_ibs Ns = Ns Sy 15 Po 32 KiB Pc Pq int
Default DDT ZAP indirect block size as a power of 2. Note that changing this
after creating a DDT on the pool will not affect existing DDTs, only newly
created ones.
.It Sy reference_history Ns = Ns Sy 3 Pq uint
Maximum reference holders being tracked when reference_tracking_enable is
active.
+.It Sy raidz_expand_max_copy_bytes Ns = Ns Sy 160MB Pq ulong
+Max amount of memory to use for RAID-Z expansion I/O.
+This limits how much I/O can be outstanding at once.
+.
+.It Sy raidz_expand_max_reflow_bytes Ns = Ns Sy 0 Pq ulong
+For testing, pause RAID-Z expansion when reflow amount reaches this value.
+.
+.It Sy raidz_io_aggregate_rows Ns = Ns Sy 4 Pq ulong
+For expanded RAID-Z, aggregate reads that have more rows than this.
+.
+.It Sy reference_history Ns = Ns Sy 3 Pq int
+Maximum reference holders being tracked when reference_tracking_enable is
+active.
.
.It Sy reference_tracking_enable Ns = Ns Sy 0 Ns | Ns 1 Pq int
Track reference holders to
most ZPL operations (e.g. write, create) will return
.Sy ENOSPC .
.
+.It Sy spa_num_allocators Ns = Ns Sy 4 Pq int
+Determines the number of block alloctators to use per spa instance.
+Capped by the number of actual CPUs in the system.
+.Pp
+Note that setting this value too high could result in performance
+degredation and/or excess fragmentation.
+.
.It Sy spa_upgrade_errlog_limit Ns = Ns Sy 0 Pq uint
Limits the number of on-disk error log entries that will be converted to the
new format when enabling the
Maximum micro ZAP size.
A micro ZAP is upgraded to a fat ZAP, once it grows beyond the specified size.
.
+.It Sy zfetch_hole_shift Ns = Ns Sy 2 Pq uint
+Log2 fraction of holes in speculative prefetch stream allowed for it to
+proceed.
+.
.It Sy zfetch_min_distance Ns = Ns Sy 4194304 Ns B Po 4 MiB Pc Pq uint
Min bytes to prefetch per stream.
Prefetch distance starts from the demand access size and quickly grows to
.It Sy zfetch_max_idistance Ns = Ns Sy 67108864 Ns B Po 64 MiB Pc Pq uint
Max bytes to prefetch indirects for per stream.
.
+.It Sy zfetch_max_reorder Ns = Ns Sy 16777216 Ns B Po 16 MiB Pc Pq uint
+Requests within this byte distance from the current prefetch stream position
+are considered parts of the stream, reordered due to parallel processing.
+Such requests do not advance the stream position immediately unless
+.Sy zfetch_hole_shift
+fill threshold is reached, but saved to fill holes in the stream later.
+.
.It Sy zfetch_max_streams Ns = Ns Sy 8 Pq uint
Max number of streams per zfetch (prefetch streams per file).
.
results in vector instructions
from the respective CPU instruction set being used.
.
+.It Sy zfs_bclone_enabled Ns = Ns Sy 1 Ns | Ns 0 Pq int
+Enable the experimental block cloning feature.
+If this setting is 0, then even if feature@block_cloning is enabled,
+attempts to clone blocks will act as though the feature is disabled.
+.
+.It Sy zfs_bclone_wait_dirty Ns = Ns Sy 0 Ns | Ns 1 Pq int
+When set to 1 the FICLONE and FICLONERANGE ioctls wait for dirty data to be
+written to disk.
+This allows the clone operation to reliably succeed when a file is
+modified and then immediately cloned.
+For small files this may be slower than making a copy of the file.
+Therefore, this setting defaults to 0 which causes a clone operation to
+immediately fail when encountering a dirty block.
+.
.It Sy zfs_blake3_impl Ns = Ns Sy fastest Pq string
Select a BLAKE3 implementation.
.Pp
4 Driver No driver retries on driver errors.
.TE
.
+.It Sy zfs_vdev_disk_max_segs Ns = Ns Sy 0 Pq uint
+Maximum number of segments to add to a BIO (min 4).
+If this is higher than the maximum allowed by the device queue or the kernel
+itself, it will be clamped.
+Setting it to zero will cause the kernel's ideal size to be used.
+This parameter only applies on Linux.
+This parameter is ignored if
+.Sy zfs_vdev_disk_classic Ns = Ns Sy 1 .
+.
+.It Sy zfs_vdev_disk_classic Ns = Ns Sy 0 Ns | Ns 1 Pq uint
+If set to 1, OpenZFS will submit IO to Linux using the method it used in 2.2
+and earlier.
+This "classic" method has known issues with highly fragmented IO requests and
+is slower on many workloads, but it has been in use for many years and is known
+to be very stable.
+If you set this parameter, please also open a bug report why you did so,
+including the workload involved and any error messages.
+.Pp
+This parameter and the classic submission method will be removed once we have
+total confidence in the new method.
+.Pp
+This parameter only applies on Linux, and can only be set at module load time.
+.
.It Sy zfs_expire_snapshot Ns = Ns Sy 300 Ns s Pq int
Time before expiring
.Pa .zfs/snapshot .
Intended to be used during pool repair or recovery to
stop resilvering when the pool is next imported.
.
+.It Sy zfs_scrub_after_expand Ns = Ns Sy 1 Ns | Ns 0 Pq int
+Automatically start a pool scrub after a RAIDZ expansion completes
+in order to verify the checksums of all blocks which have been
+copied during the expansion.
+This is enabled by default and strongly recommended.
+.
.It Sy zfs_scrub_min_time_ms Ns = Ns Sy 1000 Ns ms Po 1 s Pc Pq uint
Scrubs are processed by the sync thread.
While scrubbing, it will spend at least this much time
.It Sy zfs_sync_pass_rewrite Ns = Ns Sy 2 Pq uint
Rewrite new block pointers starting in this pass.
.
-.It Sy zfs_sync_taskq_batch_pct Ns = Ns Sy 75 Ns % Pq int
-This controls the number of threads used by
-.Sy dp_sync_taskq .
-The default value of
-.Sy 75%
-will create a maximum of one thread per CPU.
-.
.It Sy zfs_trim_extent_bytes_max Ns = Ns Sy 134217728 Ns B Po 128 MiB Pc Pq uint
Maximum size of TRIM command.
Larger ranges will be split into chunks no larger than this value before
.Sy 0 ,
generate a system-dependent value close to 6 threads per taskq.
.
+.It Sy zio_taskq_wr_iss_ncpus Ns = Ns Sy 0 Pq uint
+Determines the number of CPUs to run write issue taskqs.
+.Pp
+When 0 (the default), the value to use is computed internally
+as the number of actual CPUs in the system divided by the
+.Sy spa_num_allocators
+value.
+.
+.It Sy zio_taskq_read Ns = Ns Sy fixed,1,8 null scale null Pq charp
+Set the queue and thread configuration for the IO read queues.
+This is an advanced debugging parameter.
+Don't change this unless you understand what it does.
+.
+.It Sy zio_taskq_write Ns = Ns Sy sync fixed,1,5 scale fixed,1,5 Pq charp
+Set the queue and thread configuration for the IO write queues.
+This is an advanced debugging parameter.
+Don't change this unless you understand what it does.
+.
.It Sy zvol_inhibit_dev Ns = Ns Sy 0 Ns | Ns 1 Pq uint
Do not create zvol device nodes.
This may slightly improve startup time on
is ignored when running on a kernel that supports block multiqueue
.Pq Li blk-mq .
.
+.It Sy zvol_num_taskqs Ns = Ns Sy 0 Pq uint
+Number of zvol taskqs.
+If
+.Sy 0
+(the default) then scaling is done internally to prefer 6 threads per taskq.
+This only applies on Linux.
+.
.It Sy zvol_threads Ns = Ns Sy 0 Pq uint
The number of system wide threads to use for processing zvol block IOs.
If
projects / mirror_zfs.git / blobdiff