1.\" 2.\" This file and its contents are supplied under the terms of the 3.\" Common Development and Distribution License ("CDDL"), version 1.0. 4.\" You may only use this file in accordance with the terms of version 5.\" 1.0 of the CDDL. 6.\" 7.\" A full copy of the text of the CDDL should have accompanied this 8.\" source. A copy of the CDDL is also available via the Internet at 9.\" http://www.illumos.org/license/CDDL. 10.\" 11.\" Copyright 2014 Adam Stevko. All rights reserved. 12.\" Copyright (c) 2015 by Delphix. All rights reserved. 13.\" Copyright (c) 2020 by AJ Jordan. All rights reserved. 14.\" 15.Dd December 23, 2022 16.Dt ARCSTAT 1 17.Os 18. 19.Sh NAME 20.Nm arcstat 21.Nd report ZFS ARC and L2ARC statistics 22.Sh SYNOPSIS 23.Nm 24.Op Fl havxp 25.Op Fl f Ar field Ns Op , Ns Ar field Ns … 26.Op Fl o Ar file 27.Op Fl s Ar string 28.Op Ar interval 29.Op Ar count 30. 31.Sh DESCRIPTION 32.Nm 33prints various ZFS ARC and L2ARC statistics in vmstat-like fashion: 34.Bl -tag -compact -offset Ds -width "l2asize" 35.It Sy c 36ARC target size 37.It Sy dh% 38Demand hit percentage 39.It Sy di% 40Demand I/O hit percentage 41.It Sy dm% 42Demand miss percentage 43.It Sy ddh% 44Demand data hit percentage 45.It Sy ddi% 46Demand data I/O hit percentage 47.It Sy ddm% 48Demand data miss percentage 49.It Sy dmh% 50Demand metadata hit percentage 51.It Sy dmi% 52Demand metadata I/O hit percentage 53.It Sy dmm% 54Demand metadata miss percentage 55.It Sy mfu 56MFU list hits per second 57.It Sy mh% 58Metadata hit percentage 59.It Sy mi% 60Metadata I/O hit percentage 61.It Sy mm% 62Metadata miss percentage 63.It Sy mru 64MRU list hits per second 65.It Sy ph% 66Prefetch hits percentage 67.It Sy pi% 68Prefetch I/O hits percentage 69.It Sy pm% 70Prefetch miss percentage 71.It Sy pdh% 72Prefetch data hits percentage 73.It Sy pdi% 74Prefetch data I/O hits percentage 75.It Sy pdm% 76Prefetch data miss percentage 77.It Sy pmh% 78Prefetch metadata hits percentage 79.It Sy pmi% 80Prefetch metadata I/O hits percentage 81.It Sy pmm% 82Prefetch metadata miss percentage 83.It Sy dhit 84Demand hits per second 85.It Sy dioh 86Demand I/O hits per second 87.It Sy dmis 88Demand misses per second 89.It Sy ddhit 90Demand data hits per second 91.It Sy ddioh 92Demand data I/O hits per second 93.It Sy ddmis 94Demand data misses per second 95.It Sy dmhit 96Demand metadata hits per second 97.It Sy dmioh 98Demand metadata I/O hits per second 99.It Sy dmmis 100Demand metadata misses per second 101.It Sy hit% 102ARC hit percentage 103.It Sy hits 104ARC hits per second 105.It Sy ioh% 106ARC I/O hits percentage 107.It Sy iohs 108ARC I/O hits per second 109.It Sy mfug 110MFU ghost list hits per second 111.It Sy mhit 112Metadata hits per second 113.It Sy mioh 114Metadata I/O hits per second 115.It Sy miss 116ARC misses per second 117.It Sy mmis 118Metadata misses per second 119.It Sy mrug 120MRU ghost list hits per second 121.It Sy phit 122Prefetch hits per second 123.It Sy pioh 124Prefetch I/O hits per second 125.It Sy pmis 126Prefetch misses per second 127.It Sy pdhit 128Prefetch data hits per second 129.It Sy pdioh 130Prefetch data I/O hits per second 131.It Sy pdmis 132Prefetch data misses per second 133.It Sy pmhit 134Prefetch metadata hits per second 135.It Sy pmioh 136Prefetch metadata I/O hits per second 137.It Sy pmmis 138Prefetch metadata misses per second 139.It Sy read 140Total ARC accesses per second 141.It Sy time 142Current time 143.It Sy size 144ARC size 145.It Sy arcsz 146Alias for 147.Sy size 148.It Sy unc 149Uncached list hits per second 150.It Sy dread 151Demand accesses per second 152.It Sy ddread 153Demand data accesses per second 154.It Sy dmread 155Demand metadata accesses per second 156.It Sy eskip 157evict_skip per second 158.It Sy miss% 159ARC miss percentage 160.It Sy mread 161Metadata accesses per second 162.It Sy pread 163Prefetch accesses per second 164.It Sy pdread 165Prefetch data accesses per second 166.It Sy pmread 167Prefetch metadata accesses per second 168.It Sy l2hit% 169L2ARC access hit percentage 170.It Sy l2hits 171L2ARC hits per second 172.It Sy l2miss 173L2ARC misses per second 174.It Sy l2read 175Total L2ARC accesses per second 176.It Sy l2pref 177L2ARC prefetch allocated size per second 178.It Sy l2pref% 179L2ARC prefetch allocated size percentage 180.It Sy l2mfu 181L2ARC MFU allocated size per second 182.It Sy l2mfu% 183L2ARC MFU allocated size percentage 184.It Sy l2mru 185L2ARC MRU allocated size per second 186.It Sy l2mru% 187L2ARC MRU allocated size percentage 188.It Sy l2data 189L2ARC data (buf content) allocated size per second 190.It Sy l2data% 191L2ARC data (buf content) allocated size percentage 192.It Sy l2meta 193L2ARC metadata (buf content) allocated size per second 194.It Sy l2meta% 195L2ARC metadata (buf content) allocated size percentage 196.It Sy l2size 197Size of the L2ARC 198.It Sy mtxmis 199mutex_miss per second 200.It Sy l2bytes 201Bytes read per second from the L2ARC 202.It Sy l2wbytes 203Bytes written per second to the L2ARC 204.It Sy l2miss% 205L2ARC access miss percentage 206.It Sy l2asize 207Actual (compressed) size of the L2ARC 208.It Sy cmpsz 209Compressed size 210.It Sy cmpsz% 211Compressed size percentage 212.It Sy ovhsz 213Overhead size 214.It Sy ovhsz% 215Overhead size percentage 216.It Sy bonsz 217Bonus size 218.It Sy bonsz% 219Bonus size percentage 220.It Sy dnosz 221Dnode size 222.It Sy dnosz% 223Dnode size percentage 224.It Sy dbusz 225Dbuf size 226.It Sy dbusz% 227Dbuf size percentage 228.It Sy hdrsz 229Header size 230.It Sy hdrsz% 231Header size percentage 232.It Sy l2hsz 233L2 header size 234.It Sy l2hsz% 235L2 header size percentage 236.It Sy abdsz 237ABD chunk waste size 238.It Sy abdsz% 239ABD chunk waste size percentage 240.It Sy datatg 241ARC data target 242.It Sy datatg% 243ARC data target percentage 244.It Sy datasz 245ARC data size 246.It Sy datasz% 247ARC data size percentage 248.It Sy metatg 249ARC metadata target 250.It Sy metatg% 251ARC metadata target percentage 252.It Sy metasz 253ARC metadata size 254.It Sy metasz% 255ARC metadata size percentage 256.It Sy anosz 257Anonymous size 258.It Sy anosz% 259Anonymous size percentage 260.It Sy anoda 261Anonymous data size 262.It Sy anoda% 263Anonymous data size percentage 264.It Sy anome 265Anonymous metadata size 266.It Sy anome% 267Anonymous metadata size percentage 268.It Sy anoed 269Anonymous evictable data size 270.It Sy anoed% 271Anonymous evictable data size percentage 272.It Sy anoem 273Anonymous evictable metadata size 274.It Sy anoem% 275Anonymous evictable metadata size percentage 276.It Sy mfutg 277MFU target 278.It Sy mfutg% 279MFU target percentage 280.It Sy mfudt 281MFU data target 282.It Sy mfudt% 283MFU data target percentage 284.It Sy mfumt 285MFU metadata target 286.It Sy mfumt% 287MFU metadata target percentage 288.It Sy mfusz 289MFU size 290.It Sy mfusz% 291MFU size percentage 292.It Sy mfuda 293MFU data size 294.It Sy mfuda% 295MFU data size percentage 296.It Sy mfume 297MFU metadata size 298.It Sy mfume% 299MFU metadata size percentage 300.It Sy mfued 301MFU evictable data size 302.It Sy mfued% 303MFU evictable data size percentage 304.It Sy mfuem 305MFU evictable metadata size 306.It Sy mfuem% 307MFU evictable metadata size percentage 308.It Sy mfugsz 309MFU ghost size 310.It Sy mfugd 311MFU ghost data size 312.It Sy mfugm 313MFU ghost metadata size 314.It Sy mrutg 315MRU target 316.It Sy mrutg% 317MRU target percentage 318.It Sy mrudt 319MRU data target 320.It Sy mrudt% 321MRU data target percentage 322.It Sy mrumt 323MRU metadata target 324.It Sy mrumt% 325MRU metadata target percentage 326.It Sy mrusz 327MRU size 328.It Sy mrusz% 329MRU size percentage 330.It Sy mruda 331MRU data size 332.It Sy mruda% 333MRU data size percentage 334.It Sy mrume 335MRU metadata size 336.It Sy mrume% 337MRU metadata size percentage 338.It Sy mrued 339MRU evictable data size 340.It Sy mrued% 341MRU evictable data size percentage 342.It Sy mruem 343MRU evictable metadata size 344.It Sy mruem% 345MRU evictable metadata size percentage 346.It Sy mrugsz 347MRU ghost size 348.It Sy mrugd 349MRU ghost data size 350.It Sy mrugm 351MRU ghost metadata size 352.It Sy uncsz 353Uncached size 354.It Sy uncsz% 355Uncached size percentage 356.It Sy uncda 357Uncached data size 358.It Sy uncda% 359Uncached data size percentage 360.It Sy uncme 361Uncached metadata size 362.It Sy uncme% 363Uncached metadata size percentage 364.It Sy unced 365Uncached evictable data size 366.It Sy unced% 367Uncached evictable data size percentage 368.It Sy uncem 369Uncached evictable metadata size 370.It Sy uncem% 371Uncached evictable metadata size percentage 372.It Sy grow 373ARC grow disabled 374.It Sy need 375ARC reclaim needed 376.It Sy free 377The ARC's idea of how much free memory there is, which includes evictable memory 378in the page cache. 379Since the ARC tries to keep 380.Sy avail 381above zero, 382.Sy avail 383is usually more instructive to observe than 384.Sy free . 385.It Sy avail 386The ARC's idea of how much free memory is available to it, which is a bit less 387than 388.Sy free . 389May temporarily be negative, in which case the ARC will reduce the target size 390.Sy c . 391.El 392. 393.Sh OPTIONS 394.Bl -tag -width "-v" 395.It Fl a 396Print all possible stats. 397.It Fl f 398Display only specific fields. 399See 400.Sx DESCRIPTION 401for supported statistics. 402.It Fl h 403Display help message. 404.It Fl o 405Report statistics to a file instead of the standard output. 406.It Fl p 407Disable auto-scaling of numerical fields (for raw, machine-parsable values). 408.It Fl s 409Display data with a specified separator (default: 2 spaces). 410.It Fl x 411Print extended stats 412.Pq same as Fl f Sy time , Ns Sy mfu , Ns Sy mru , Ns Sy mfug , Ns Sy mrug , Ns Sy eskip , Ns Sy mtxmis , Ns Sy dread , Ns Sy pread , Ns Sy read . 413.It Fl v 414Show field headers and definitions 415.El 416. 417.Sh OPERANDS 418The following operands are supported: 419.Bl -tag -compact -offset Ds -width "interval" 420.It Ar interval 421Specify the sampling interval in seconds. 422.It Ar count 423Display only 424.Ar count 425reports. 426.El 427