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@grahams
Created January 23, 2026 18:13
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------------------------------------------------------------------------
ZFS Subsystem Report Fri Jan 23 13:12:50 2026
Linux 6.12.33-production+truenas 2.3.4-1
Machine: bobbynewmark (x86_64) 2.3.4-1
ARC status:
Total memory size: 125.5 GiB
Min target size: 3.1 % 3.9 GiB
Max target size: 99.2 % 124.5 GiB
Target size (adaptive): 63.3 % 78.8 GiB
Current size: 63.3 % 78.8 GiB
Free memory size: 5.7 GiB
Available memory size: 1.4 GiB
ARC structural breakdown (current size): 78.8 GiB
Compressed size: 83.5 % 65.8 GiB
Overhead size: 7.0 % 5.5 GiB
Bonus size: 1.0 % 812.3 MiB
Dnode size: 3.2 % 2.5 GiB
Dbuf size: 1.4 % 1.1 GiB
Header size: 0.8 % 651.6 MiB
L2 header size: 3.1 % 2.5 GiB
ABD chunk waste size: 0.1 % 49.0 MiB
ARC types breakdown (compressed + overhead): 71.3 GiB
Data size: 90.1 % 64.2 GiB
Metadata size: 9.9 % 7.1 GiB
ARC states breakdown (compressed + overhead): 71.3 GiB
Anonymous data size: < 0.1 % 12.1 MiB
Anonymous metadata size: < 0.1 % 8.4 MiB
MFU data target: 39.3 % 28.0 GiB
MFU data size: 37.0 % 26.4 GiB
MFU evictable data size: 35.8 % 25.6 GiB
MFU ghost data size: 15.7 GiB
MFU metadata target: 4.4 % 3.2 GiB
MFU metadata size: 5.7 % 4.1 GiB
MFU evictable metadata size: 0.9 % 678.2 MiB
MFU ghost metadata size: 5.4 GiB
MRU data target: 49.9 % 35.6 GiB
MRU data size: 53.0 % 37.8 GiB
MRU evictable data size: 49.5 % 35.3 GiB
MRU ghost data size: 16.7 GiB
MRU metadata target: 6.3 % 4.5 GiB
MRU metadata size: 4.2 % 3.0 GiB
MRU evictable metadata size: 1.5 % 1.1 GiB
MRU ghost metadata size: 19.0 GiB
Uncached data size: < 0.1 % 36.2 MiB
Uncached metadata size: < 0.1 % 56.5 KiB
ARC hash breakdown:
Elements: 30.2M
Collisions: 398.5M
Chain max: 15
Chains: 9.0M
ARC misc:
Uncompressed size: 114.2 % 75.1 GiB
Memory throttles: 0
Memory direct reclaims: 93432
Memory indirect reclaims: 9080429
Deleted: 158.9M
Mutex misses: 948.2k
Eviction skips: 591.4M
Eviction skips due to L2 writes: 14.9k
L2 cached evictions: 15.5 TiB
L2 eligible evictions: 306.5 GiB
L2 eligible MFU evictions: 7.5 % 23.0 GiB
L2 eligible MRU evictions: 92.5 % 283.5 GiB
L2 ineligible evictions: 2.9 TiB
ARC total accesses: 34.9G
Total hits: 99.3 % 34.7G
Total I/O hits: 0.2 % 77.4M
Total misses: 0.5 % 180.9M
ARC demand data accesses: 89.0 % 31.1G
Demand data hits: 99.9 % 31.1G
Demand data I/O hits: < 0.1 % 3.4M
Demand data misses: 0.1 % 19.7M
ARC demand metadata accesses: 9.0 % 3.2G
Demand metadata hits: 97.9 % 3.1G
Demand metadata I/O hits: 1.7 % 54.6M
Demand metadata misses: 0.3 % 10.7M
ARC prefetch data accesses: 0.7 % 232.5M
Prefetch data hits: 34.1 % 79.2M
Prefetch data I/O hits: 7.0 % 16.2M
Prefetch data misses: 59.0 % 137.1M
ARC prefetch metadata accesses: 1.3 % 456.8M
Prefetch metadata hits: 96.4 % 440.2M
Prefetch metadata I/O hits: 0.7 % 3.2M
Prefetch metadata misses: 2.9 % 13.4M
ARC predictive prefetches: 36.2 % 249.8M
Demand hits after predictive: 27.1 % 67.7M
Demand I/O hits after predictive: 1.6 % 4.1M
Never demanded after predictive: 71.3 % 178.0M
ARC prescient prefetches: 63.8 % 439.5M
Demand hits after prescient: 1.4 % 6.3M
Demand I/O hits after prescient: < 0.1 % 27.6k
Never demanded after prescient: 98.6 % 433.2M
ARC states hits of all accesses:
Most frequently used (MFU): 96.7 % 33.8G
Most recently used (MRU): 2.5 % 866.4M
Most frequently used (MFU) ghost: < 0.1 % 16.4M
Most recently used (MRU) ghost: < 0.1 % 12.8M
Uncached: < 0.1 % 10.8M
DMU predictive prefetcher calls: 31.2G
Stream hits: 2.8 % 871.9M
Hits ahead of stream: 11.0 % 3.4G
Hits behind stream: 81.8 % 25.5G
Stream misses: 4.4 % 1.4G
Streams limit reached: 77.6 % 1.1G
Stream strides: 5.6M
Prefetches issued 67.0M
L2ARC status: HEALTHY
Low memory aborts: 463
Free on write: 22.9k
R/W clashes: 2
Bad checksums: 0
Read errors: 0
Write errors: 0
L2ARC size (adaptive): 3.1 TiB
Compressed: 97.4 % 3.0 TiB
Header size: 0.1 % 2.5 GiB
MFU allocated size: 12.1 % 370.1 GiB
MRU allocated size: 73.1 % 2.2 TiB
Prefetch allocated size: 14.9 % 453.0 GiB
Data (buffer content) allocated size: 99.9 % 3.0 TiB
Metadata (buffer content) allocated size: 0.2 % 5.5 GiB
L2ARC breakdown: 180.5M
Hit ratio: 61.8 % 111.6M
Miss ratio: 38.2 % 68.9M
L2ARC I/O:
Reads: 10.5 TiB 111.6M
Writes: 5.4 TiB 834.7k
L2ARC evicts:
L1 cached: 1.1M
While reading: 0
Solaris Porting Layer (SPL):
spl_hostid 0
spl_hostid_path /etc/hostid
spl_kmem_alloc_max 16777216
spl_kmem_alloc_warn 65536
spl_kmem_cache_kmem_threads 4
spl_kmem_cache_magazine_size 0
spl_kmem_cache_max_size 32
spl_kmem_cache_obj_per_slab 8
spl_kmem_cache_slab_limit 16384
spl_panic_halt 1
spl_schedule_hrtimeout_slack_us 0
spl_taskq_kick 0
spl_taskq_thread_bind 0
spl_taskq_thread_dynamic 1
spl_taskq_thread_priority 1
spl_taskq_thread_sequential 4
spl_taskq_thread_timeout_ms 5000
Tunables:
brt_zap_default_bs 12
brt_zap_default_ibs 12
brt_zap_prefetch 1
dbuf_cache_hiwater_pct 10
dbuf_cache_lowater_pct 10
dbuf_cache_max_bytes 18446744073709551615
dbuf_cache_shift 5
dbuf_metadata_cache_max_bytes 18446744073709551615
dbuf_metadata_cache_shift 6
dbuf_mutex_cache_shift 0
ddt_zap_default_bs 15
ddt_zap_default_ibs 15
dmu_ddt_copies 0
dmu_object_alloc_chunk_shift 7
dmu_prefetch_max 134217728
icp_aes_impl cycle [fastest] generic x86_64 aesni
icp_gcm_avx_chunk_size 32736
icp_gcm_impl cycle [fastest] avx generic pclmulqdq
l2arc_exclude_special 0
l2arc_feed_again 1
l2arc_feed_min_ms 200
l2arc_feed_secs 1
l2arc_headroom 8
l2arc_headroom_boost 200
l2arc_meta_percent 33
l2arc_mfuonly 0
l2arc_noprefetch 1
l2arc_norw 0
l2arc_rebuild_blocks_min_l2size 1073741824
l2arc_rebuild_enabled 1
l2arc_trim_ahead 0
l2arc_write_boost 33554432
l2arc_write_max 33554432
metaslab_aliquot 2097152
metaslab_bias_enabled 1
metaslab_debug_load 0
metaslab_debug_unload 0
metaslab_df_max_search 16777216
metaslab_df_use_largest_segment 0
metaslab_force_ganging 16777217
metaslab_force_ganging_pct 3
metaslab_fragmentation_factor_enabled 1
metaslab_lba_weighting_enabled 1
metaslab_perf_bias 1
metaslab_preload_enabled 1
metaslab_preload_limit 10
metaslab_preload_pct 50
metaslab_unload_delay 32
metaslab_unload_delay_ms 600000
raidz_expand_max_copy_bytes 167772160
raidz_expand_max_reflow_bytes 0
raidz_io_aggregate_rows 4
send_holes_without_birth_time 1
spa_asize_inflation 24
spa_config_path /etc/zfs/zpool.cache
spa_cpus_per_allocator 4
spa_load_print_vdev_tree 0
spa_load_verify_data 1
spa_load_verify_metadata 1
spa_load_verify_shift 4
spa_num_allocators 4
spa_slop_shift 5
spa_upgrade_errlog_limit 0
vdev_file_logical_ashift 9
vdev_file_physical_ashift 9
vdev_removal_max_span 32768
vdev_validate_skip 0
zap_iterate_prefetch 1
zap_micro_max_size 131072
zap_shrink_enabled 1
zfetch_hole_shift 2
zfetch_max_distance 67108864
zfetch_max_idistance 134217728
zfetch_max_reorder 16777216
zfetch_max_sec_reap 2
zfetch_max_streams 8
zfetch_min_distance 4194304
zfetch_min_sec_reap 1
zfs_abd_scatter_enabled 1
zfs_abd_scatter_max_order 13
zfs_abd_scatter_min_size 1536
zfs_active_allocator dynamic
zfs_admin_snapshot 0
zfs_allow_redacted_dataset_mount 0
zfs_arc_average_blocksize 8192
zfs_arc_dnode_limit 0
zfs_arc_dnode_limit_percent 10
zfs_arc_dnode_reduce_percent 10
zfs_arc_evict_batch_limit 10
zfs_arc_evict_threads 4
zfs_arc_eviction_pct 200
zfs_arc_grow_retry 0
zfs_arc_lotsfree_percent 10
zfs_arc_max 0
zfs_arc_meta_balance 500
zfs_arc_min 0
zfs_arc_min_prefetch_ms 0
zfs_arc_min_prescient_prefetch_ms 0
zfs_arc_pc_percent 300
zfs_arc_prune_task_threads 1
zfs_arc_shrink_shift 0
zfs_arc_shrinker_limit 0
zfs_arc_shrinker_seeks 2
zfs_arc_sys_free 0
zfs_async_block_max_blocks 18446744073709551615
zfs_autoimport_disable 1
zfs_bclone_enabled 1
zfs_bclone_wait_dirty 1
zfs_blake3_impl cycle [fastest] generic sse2 sse41 avx2
zfs_btree_verify_intensity 0
zfs_checksum_events_per_second 20
zfs_commit_timeout_pct 10
zfs_compressed_arc_enabled 1
zfs_condense_indirect_commit_entry_delay_ms 0
zfs_condense_indirect_obsolete_pct 25
zfs_condense_indirect_vdevs_enable 1
zfs_condense_max_obsolete_bytes 1073741824
zfs_condense_min_mapping_bytes 131072
zfs_dbgmsg_enable 1
zfs_dbgmsg_maxsize 4194304
zfs_dbuf_state_index 0
zfs_ddt_data_is_special 1
zfs_deadman_checktime_ms 60000
zfs_deadman_enabled 1
zfs_deadman_events_per_second 1
zfs_deadman_failmode wait
zfs_deadman_synctime_ms 600000
zfs_deadman_ziotime_ms 300000
zfs_dedup_log_cap 4294967295
zfs_dedup_log_flush_entries_max 4294967295
zfs_dedup_log_flush_entries_min 200
zfs_dedup_log_flush_flow_rate_txgs 10
zfs_dedup_log_flush_min_time_ms 1000
zfs_dedup_log_flush_txgs 100
zfs_dedup_log_hard_cap 0
zfs_dedup_log_mem_max 1348060037
zfs_dedup_log_mem_max_percent 1
zfs_dedup_log_txg_max 8
zfs_dedup_prefetch 0
zfs_default_bs 9
zfs_default_ibs 15
zfs_delay_min_dirty_percent 60
zfs_delay_scale 500000
zfs_delete_blocks 20480
zfs_dio_enabled 1
zfs_dio_strict 0
zfs_dio_write_verify_events_per_second 20
zfs_dirty_data_max 4294967296
zfs_dirty_data_max_max 4294967296
zfs_dirty_data_max_max_percent 25
zfs_dirty_data_max_percent 10
zfs_dirty_data_sync_percent 20
zfs_disable_ivset_guid_check 0
zfs_dmu_offset_next_sync 1
zfs_embedded_slog_min_ms 64
zfs_expire_snapshot 300
zfs_fallocate_reserve_percent 110
zfs_flags 0
zfs_fletcher_4_impl [fastest] scalar superscalar superscalar4 sse2 ssse3 avx2
zfs_free_bpobj_enabled 1
zfs_free_leak_on_eio 0
zfs_free_min_time_ms 1000
zfs_history_output_max 1048576
zfs_immediate_write_sz 32768
zfs_initialize_chunk_size 1048576
zfs_initialize_value 16045690984833335022
zfs_keep_log_spacemaps_at_export 0
zfs_key_max_salt_uses 400000000
zfs_livelist_condense_new_alloc 0
zfs_livelist_condense_sync_cancel 0
zfs_livelist_condense_sync_pause 0
zfs_livelist_condense_zthr_cancel 0
zfs_livelist_condense_zthr_pause 0
zfs_livelist_max_entries 500000
zfs_livelist_min_percent_shared 75
zfs_lua_max_instrlimit 100000000
zfs_lua_max_memlimit 104857600
zfs_max_async_dedup_frees 100000
zfs_max_dataset_nesting 50
zfs_max_log_walking 5
zfs_max_logsm_summary_length 10
zfs_max_missing_tvds 0
zfs_max_nvlist_src_size 0
zfs_max_recordsize 16777216
zfs_metaslab_find_max_tries 100
zfs_metaslab_fragmentation_threshold 77
zfs_metaslab_max_size_cache_sec 3600
zfs_metaslab_mem_limit 25
zfs_metaslab_segment_weight_enabled 1
zfs_metaslab_switch_threshold 2
zfs_metaslab_try_hard_before_gang 0
zfs_mg_fragmentation_threshold 95
zfs_mg_noalloc_threshold 0
zfs_min_metaslabs_to_flush 1
zfs_multihost_fail_intervals 10
zfs_multihost_history 0
zfs_multihost_import_intervals 20
zfs_multihost_interval 1000
zfs_multilist_num_sublists 0
zfs_no_scrub_io 0
zfs_no_scrub_prefetch 0
zfs_nocacheflush 0
zfs_nopwrite_enabled 1
zfs_object_mutex_size 64
zfs_obsolete_min_time_ms 500
zfs_override_estimate_recordsize 0
zfs_pd_bytes_max 52428800
zfs_per_txg_dirty_frees_percent 30
zfs_prefetch_disable 0
zfs_read_history 0
zfs_read_history_hits 0
zfs_rebuild_max_segment 1048576
zfs_rebuild_scrub_enabled 1
zfs_rebuild_vdev_limit 67108864
zfs_reconstruct_indirect_combinations_max 4096
zfs_recover 0
zfs_recv_best_effort_corrective 0
zfs_recv_queue_ff 20
zfs_recv_queue_length 16777216
zfs_recv_write_batch_size 1048576
zfs_removal_ignore_errors 0
zfs_removal_suspend_progress 0
zfs_remove_max_segment 16777216
zfs_resilver_defer_percent 10
zfs_resilver_disable_defer 0
zfs_resilver_min_time_ms 3000
zfs_scan_blkstats 0
zfs_scan_checkpoint_intval 7200
zfs_scan_fill_weight 3
zfs_scan_ignore_errors 0
zfs_scan_issue_strategy 0
zfs_scan_legacy 0
zfs_scan_max_ext_gap 2097152
zfs_scan_mem_lim_fact 20
zfs_scan_mem_lim_soft_fact 20
zfs_scan_report_txgs 0
zfs_scan_strict_mem_lim 0
zfs_scan_suspend_progress 0
zfs_scan_vdev_limit 16777216
zfs_scrub_after_expand 1
zfs_scrub_error_blocks_per_txg 4096
zfs_scrub_min_time_ms 1000
zfs_send_corrupt_data 0
zfs_send_no_prefetch_queue_ff 20
zfs_send_no_prefetch_queue_length 1048576
zfs_send_queue_ff 20
zfs_send_queue_length 16777216
zfs_send_unmodified_spill_blocks 1
zfs_sha256_impl cycle [fastest] generic x64 ssse3 avx avx2 shani
zfs_sha512_impl cycle [fastest] generic x64 avx avx2
zfs_slow_io_events_per_second 20
zfs_snapshot_history_enabled 1
zfs_snapshot_no_setuid 0
zfs_spa_discard_memory_limit 16777216
zfs_special_class_metadata_reserve_pct 25
zfs_sync_pass_deferred_free 2
zfs_sync_pass_dont_compress 8
zfs_sync_pass_rewrite 2
zfs_traverse_indirect_prefetch_limit 32
zfs_trim_extent_bytes_max 134217728
zfs_trim_extent_bytes_min 32768
zfs_trim_metaslab_skip 0
zfs_trim_queue_limit 10
zfs_trim_txg_batch 32
zfs_txg_history 100
zfs_txg_timeout 5
zfs_unflushed_log_block_max 131072
zfs_unflushed_log_block_min 1000
zfs_unflushed_log_block_pct 400
zfs_unflushed_log_txg_max 1000
zfs_unflushed_max_mem_amt 1073741824
zfs_unflushed_max_mem_ppm 1000
zfs_unlink_suspend_progress 0
zfs_user_indirect_is_special 1
zfs_vdev_aggregation_limit 1048576
zfs_vdev_aggregation_limit_non_rotating 131072
zfs_vdev_async_read_max_active 3
zfs_vdev_async_read_min_active 1
zfs_vdev_async_write_active_max_dirty_percent 60
zfs_vdev_async_write_active_min_dirty_percent 30
zfs_vdev_async_write_max_active 10
zfs_vdev_async_write_min_active 2
zfs_vdev_default_ms_count 200
zfs_vdev_default_ms_shift 29
zfs_vdev_direct_write_verify 1
zfs_vdev_disk_classic 0
zfs_vdev_disk_max_segs 0
zfs_vdev_failfast_mask 1
zfs_vdev_initializing_max_active 1
zfs_vdev_initializing_min_active 1
zfs_vdev_max_active 1000
zfs_vdev_max_auto_ashift 14
zfs_vdev_max_ms_shift 34
zfs_vdev_min_auto_ashift 9
zfs_vdev_min_ms_count 16
zfs_vdev_mirror_non_rotating_inc 0
zfs_vdev_mirror_non_rotating_seek_inc 1
zfs_vdev_mirror_rotating_inc 0
zfs_vdev_mirror_rotating_seek_inc 5
zfs_vdev_mirror_rotating_seek_offset 1048576
zfs_vdev_ms_count_limit 131072
zfs_vdev_nia_credit 5
zfs_vdev_nia_delay 5
zfs_vdev_open_timeout_ms 1000
zfs_vdev_raidz_impl cycle [fastest] original scalar sse2 ssse3 avx2
zfs_vdev_read_gap_limit 32768
zfs_vdev_rebuild_max_active 3
zfs_vdev_rebuild_min_active 1
zfs_vdev_removal_max_active 2
zfs_vdev_removal_min_active 1
zfs_vdev_scheduler unused
zfs_vdev_scrub_max_active 3
zfs_vdev_scrub_min_active 1
zfs_vdev_sync_read_max_active 10
zfs_vdev_sync_read_min_active 10
zfs_vdev_sync_write_max_active 10
zfs_vdev_sync_write_min_active 10
zfs_vdev_trim_max_active 2
zfs_vdev_trim_min_active 1
zfs_vdev_write_gap_limit 4096
zfs_vnops_read_chunk_size 33554432
zfs_wrlog_data_max 8589934592
zfs_xattr_compat 0
zfs_zevent_len_max 512
zfs_zevent_retain_expire_secs 900
zfs_zevent_retain_max 2000
zfs_zil_clean_taskq_maxalloc 1048576
zfs_zil_clean_taskq_minalloc 1024
zfs_zil_clean_taskq_nthr_pct 100
zfs_zil_saxattr 1
zil_maxblocksize 131072
zil_maxcopied 7680
zil_nocacheflush 0
zil_replay_disable 0
zil_slog_bulk 67108864
zio_deadman_log_all 0
zio_dva_throttle_enabled 1
zio_requeue_io_start_cut_in_line 1
zio_slow_io_ms 30000
zio_taskq_batch_pct 80
zio_taskq_batch_tpq 0
zio_taskq_read fixed,1,8 null scale null
zio_taskq_write sync null scale null
zio_taskq_write_tpq 16
zstd_abort_size 131072
zstd_earlyabort_pass 1
zvol_bclone_enabled 1
zvol_blk_mq_blocks_per_thread 8
zvol_blk_mq_queue_depth 128
zvol_enforce_quotas 1
zvol_inhibit_dev 0
zvol_major 230
zvol_max_copy_bytes 0
zvol_max_discard_blocks 16384
zvol_num_taskqs 0
zvol_open_timeout_ms 1000
zvol_prefetch_bytes 131072
zvol_request_sync 0
zvol_threads 0
zvol_use_blk_mq 0
zvol_volmode 2
ZIL committed transactions: 119.8M
Commit requests: 9.1M
Flushes to stable storage: 9.1M
Transactions to SLOG storage pool: 1.6 TiB 21.2M
Transactions to non-SLOG storage pool: 470.7 MiB 14.8k
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