'\" te
.\" Copyright (c) 2013 by Turbo Fredriksson <turbo@bayour.com>. All rights reserved.
.\" Copyright (c) 2017 Datto Inc.
+.\" Copyright (c) 2018 by Delphix. All rights reserved.
.\" 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
Default value: \fB0\fR.
.RE
+.sp
+.ne 2
+.na
+\fBdbuf_metadata_cache_max_bytes\fR (ulong)
+.ad
+.RS 12n
+Maximum size in bytes of the metadata dbuf cache. When \fB0\fR this value will
+default to \fB1/2^dbuf_cache_shift\fR (1/16) of the target ARC size, otherwise
+the provided value in bytes will be used. The behavior of the metadata dbuf
+cache and its associated settings can be observed via the
+\fB/proc/spl/kstat/zfs/dbufstats\fR kstat.
+.sp
+Default value: \fB0\fR.
+.RE
+
.sp
.ne 2
.na
Default value: \fB5\fR.
.RE
+.sp
+.ne 2
+.na
+\fBdbuf_metadata_cache_shift\fR (int)
+.ad
+.RS 12n
+Set the size of the dbuf metadata cache, \fBdbuf_metadata_cache_max_bytes\fR,
+to a log2 fraction of the target arc size.
+.sp
+Default value: \fB6\fR.
+.RE
+
.sp
.ne 2
.na
Use \fB1\fR for yes (default) and \fB0\fR for no.
.RE
+.sp
+.ne 2
+.na
+\fBmetaslab_force_ganging\fR (ulong)
+.ad
+.RS 12n
+Make some blocks above a certain size be gang blocks. This option is used
+by the test suite to facilitate testing.
+.sp
+Default value: \fB16,777,217\fR.
+.RE
+
.sp
.ne 2
.na
.sp
.ne 2
.na
-\fBmetaslabs_per_vdev\fR (int)
+\fBvdev_max_ms_count\fR (int)
.ad
.RS 12n
-When a vdev is added, it will be divided into approximately (but no more than) this number of metaslabs.
+When a vdev is added target this number of metaslabs per top-level vdev.
.sp
Default value: \fB200\fR.
.RE
+.sp
+.ne 2
+.na
+\fBvdev_min_ms_count\fR (int)
+.ad
+.RS 12n
+Minimum number of metaslabs to create in a top-level vdev.
+.sp
+Default value: \fB16\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBvdev_ms_count_limit\fR (int)
+.ad
+.RS 12n
+Practical upper limit of total metaslabs per top-level vdev.
+.sp
+Default value: \fB131,072\fR.
+.RE
+
.sp
.ne 2
.na
Default value: \fB24\fR.
.RE
+.sp
+.ne 2
+.na
+\fBspa_load_print_vdev_tree\fR (int)
+.ad
+.RS 12n
+Whether to print the vdev tree in the debugging message buffer during pool import.
+Use 0 to disable and 1 to enable.
+.sp
+Default value: \fB0\fR.
+.RE
+
.sp
.ne 2
.na
Default value: \fB5\fR.
.RE
+.sp
+.ne 2
+.na
+\fBvdev_removal_max_span\fR (int)
+.ad
+.RS 12n
+During top-level vdev removal, chunks of data are copied from the vdev
+which may include free space in order to trade bandwidth for IOPS.
+This parameter determines the maximum span of free space (in bytes)
+which will be included as "unnecessary" data in a chunk of copied data.
+
+The default value here was chosen to align with
+\fBzfs_vdev_read_gap_limit\fR, which is a similar concept when doing
+regular reads (but there's no reason it has to be the same).
+.sp
+Default value: \fB32,768\fR.
+.RE
+
.sp
.ne 2
.na
Default value: \fB0\fR.
.RE
+.sp
+.ne 2
+.na
+\fBzfs_max_missing_tvds\fR (int)
+.ad
+.RS 12n
+Number of missing top-level vdevs which will be allowed during
+pool import (only in read-only mode).
+.sp
+Default value: \fB0\fR
+.RE
+
.sp
.ne 2
.na
Default value: \fB5\fR%.
.RE
+.sp
+.ne 2
+.na
+\fBzfs_condense_indirect_vdevs_enable\fR (int)
+.ad
+.RS 12n
+Enable condensing indirect vdev mappings. When set to a non-zero value,
+attempt to condense indirect vdev mappings if the mapping uses more than
+\fBzfs_condense_min_mapping_bytes\fR bytes of memory and if the obsolete
+space map object uses more than \fBzfs_condense_max_obsolete_bytes\fR
+bytes on-disk. The condensing process is an attempt to save memory by
+removing obsolete mappings.
+.sp
+Default value: \fB1\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBzfs_condense_max_obsolete_bytes\fR (ulong)
+.ad
+.RS 12n
+Only attempt to condense indirect vdev mappings if the on-disk size
+of the obsolete space map object is greater than this number of bytes
+(see \fBfBzfs_condense_indirect_vdevs_enable\fR).
+.sp
+Default value: \fB1,073,741,824\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBzfs_condense_min_mapping_bytes\fR (ulong)
+.ad
+.RS 12n
+Minimum size vdev mapping to attempt to condense (see
+\fBzfs_condense_indirect_vdevs_enable\fR).
+.sp
+Default value: \fB131,072\fR.
+.RE
+
.sp
.ne 2
.na
Default value: \fB100,000\fR.
.RE
+.sp
+.ne 2
+.na
+\fBzfs_override_estimate_recordsize\fR (ulong)
+.ad
+.RS 12n
+Record size calculation override for zfs send estimates.
+.sp
+Default value: \fB0\fR.
+.RE
+
.sp
.ne 2
.na
16 ZFS_DEBUG_MODIFY
Check for illegally modified ARC buffers.
_
-32 ZFS_DEBUG_SPA
- Enable spa_dbgmsg entries in the debug log.
-_
64 ZFS_DEBUG_ZIO_FREE
Enable verification of block frees.
_
Default value: \fB32,768\fR.
.RE
+.sp
+.ne 2
+.na
+\fBzfs_lua_max_instrlimit\fR (ulong)
+.ad
+.RS 12n
+The maximum execution time limit that can be set for a ZFS channel program,
+specified as a number of Lua instructions.
+.sp
+Default value: \fB100,000,000\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBzfs_lua_max_memlimit\fR (ulong)
+.ad
+.RS 12n
+The maximum memory limit that can be set for a ZFS channel program, specified
+in bytes.
+.sp
+Default value: \fB104,857,600\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBzfs_max_dataset_nesting\fR (int)
+.ad
+.RS 12n
+The maximum depth of nested datasets. This value can be tuned temporarily to
+fix existing datasets that exceed the predefined limit.
+.sp
+Default value: \fB50\fR.
+.RE
+
.sp
.ne 2
.na
Default value: \fB0\fR.
.RE
+.sp
+.ne 2
+.na
+\fBzfs_ddt_data_is_special\fR (int)
+.ad
+.RS 12n
+If enabled, ZFS will place DDT data into the special allocation class.
+.sp
+Default value: \fB1\fR.
+.RE
+
+.sp
+.ne 2
+.na
+\fBzfs_user_indirect_is_special\fR (int)
+.ad
+.RS 12n
+If enabled, ZFS will place user data (both file and zvol) indirect blocks
+into the special allocation class.
+.sp
+Default value: \fB1\fR.
+.RE
+
.sp
.ne 2
.na
Use \fB1\fR for yes and \fB0\fR for no (default).
.RE
+.sp
+.ne 2
+.na
+\fBzfs_reconstruct_indirect_combinations_max\fR (int)
+.ad
+.RS 12na
+If an indirect split block contains more than this many possible unique
+combinations when being reconstructed, consider it too computationally
+expensive to check them all. Instead, try at most
+\fBzfs_reconstruct_indirect_combinations_max\fR randomly-selected
+combinations each time the block is accessed. This allows all segment
+copies to participate fairly in the reconstruction when all combinations
+cannot be checked and prevents repeated use of one bad copy.
+.sp
+Default value: \fB100\fR.
+.RE
+
.sp
.ne 2
.na
To preserve progress across reboots the sequential scan algorithm periodically
needs to stop metadata scanning and issue all the verifications I/Os to disk.
The frequency of this flushing is determined by the
-\fBfBzfs_scan_checkpoint_intval\fR tunable.
+\fBzfs_scan_checkpoint_intval\fR tunable.
.sp
Default value: \fB7200\fR seconds (every 2 hours).
.RE
Default value: \fB2\fR.
.RE
+.sp
+.ne 2
+.na
+\fBzfs_spa_discard_memory_limit\fR (int)
+.ad
+.RS 12n
+Maximum memory used for prefetching a checkpoint's space map on each
+vdev while discarding the checkpoint.
+.sp
+Default value: \fB16,777,216\fR.
+.RE
+
.sp
.ne 2
.na
Default value: \fB786,432\fR.
.RE
+.sp
+.ne 2
+.na
+\fBzio_decompress_fail_fraction\fR (int)
+.ad
+.RS 12n
+If non-zero, this value represents the denominator of the probability that zfs
+should induce a decompression failure. For instance, for a 5% decompression
+failure rate, this value should be set to 20.
+.sp
+Default value: \fB0\fR.
+.RE
+
.sp
.ne 2
.na
projects / mirror_zfs.git / blobdiff