1 /* 2 * CDDL HEADER START 3 * 4 * The contents of this file are subject to the terms of the 5 * Common Development and Distribution License (the "License"). 6 * You may not use this file except in compliance with the License. 7 * 8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE 9 * or https://opensource.org/licenses/CDDL-1.0. 10 * See the License for the specific language governing permissions 11 * and limitations under the License. 12 * 13 * When distributing Covered Code, include this CDDL HEADER in each 14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE. 15 * If applicable, add the following below this CDDL HEADER, with the 16 * fields enclosed by brackets "[]" replaced with your own identifying 17 * information: Portions Copyright [yyyy] [name of copyright owner] 18 * 19 * CDDL HEADER END 20 */ 21 /* 22 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. 23 * Copyright (c) 2013, Delphix. All rights reserved. 24 * Copyright (c) 2013, Saso Kiselkov. All rights reserved. 25 * Copyright (c) 2013, Nexenta Systems, Inc. All rights reserved. 26 * Copyright (c) 2020, George Amanakis. All rights reserved. 27 */ 28 29 #ifndef _SYS_ARC_IMPL_H 30 #define _SYS_ARC_IMPL_H 31 32 #include <sys/arc.h> 33 #include <sys/multilist.h> 34 #include <sys/zio_crypt.h> 35 #include <sys/zthr.h> 36 #include <sys/aggsum.h> 37 #include <sys/wmsum.h> 38 39 #ifdef __cplusplus 40 extern "C" { 41 #endif 42 43 /* 44 * Note that buffers can be in one of 6 states: 45 * ARC_anon - anonymous (discussed below) 46 * ARC_mru - recently used, currently cached 47 * ARC_mru_ghost - recently used, no longer in cache 48 * ARC_mfu - frequently used, currently cached 49 * ARC_mfu_ghost - frequently used, no longer in cache 50 * ARC_uncached - uncacheable prefetch, to be evicted 51 * ARC_l2c_only - exists in L2ARC but not other states 52 * When there are no active references to the buffer, they are 53 * are linked onto a list in one of these arc states. These are 54 * the only buffers that can be evicted or deleted. Within each 55 * state there are multiple lists, one for meta-data and one for 56 * non-meta-data. Meta-data (indirect blocks, blocks of dnodes, 57 * etc.) is tracked separately so that it can be managed more 58 * explicitly: favored over data, limited explicitly. 59 * 60 * Anonymous buffers are buffers that are not associated with 61 * a DVA. These are buffers that hold dirty block copies 62 * before they are written to stable storage. By definition, 63 * they are "ref'd" and are considered part of arc_mru 64 * that cannot be freed. Generally, they will acquire a DVA 65 * as they are written and migrate onto the arc_mru list. 66 * 67 * The ARC_l2c_only state is for buffers that are in the second 68 * level ARC but no longer in any of the ARC_m* lists. The second 69 * level ARC itself may also contain buffers that are in any of 70 * the ARC_m* states - meaning that a buffer can exist in two 71 * places. The reason for the ARC_l2c_only state is to keep the 72 * buffer header in the hash table, so that reads that hit the 73 * second level ARC benefit from these fast lookups. 74 */ 75 76 typedef struct arc_state { 77 /* 78 * list of evictable buffers 79 */ 80 multilist_t arcs_list[ARC_BUFC_NUMTYPES]; 81 /* 82 * supports the "dbufs" kstat 83 */ 84 arc_state_type_t arcs_state; 85 /* 86 * total amount of data in this state. 87 */ 88 zfs_refcount_t arcs_size[ARC_BUFC_NUMTYPES] ____cacheline_aligned; 89 /* 90 * total amount of evictable data in this state 91 */ 92 zfs_refcount_t arcs_esize[ARC_BUFC_NUMTYPES]; 93 /* 94 * amount of hit bytes for this state (counted only for ghost states) 95 */ 96 wmsum_t arcs_hits[ARC_BUFC_NUMTYPES]; 97 } arc_state_t; 98 99 typedef struct arc_callback arc_callback_t; 100 101 struct arc_callback { 102 void *acb_private; 103 arc_read_done_func_t *acb_done; 104 arc_buf_t *acb_buf; 105 boolean_t acb_encrypted; 106 boolean_t acb_compressed; 107 boolean_t acb_noauth; 108 boolean_t acb_nobuf; 109 boolean_t acb_wait; 110 int acb_wait_error; 111 kmutex_t acb_wait_lock; 112 kcondvar_t acb_wait_cv; 113 zbookmark_phys_t acb_zb; 114 zio_t *acb_zio_dummy; 115 zio_t *acb_zio_head; 116 arc_callback_t *acb_prev; 117 arc_callback_t *acb_next; 118 }; 119 120 typedef struct arc_write_callback arc_write_callback_t; 121 122 struct arc_write_callback { 123 void *awcb_private; 124 arc_write_done_func_t *awcb_ready; 125 arc_write_done_func_t *awcb_children_ready; 126 arc_write_done_func_t *awcb_done; 127 arc_buf_t *awcb_buf; 128 }; 129 130 /* 131 * ARC buffers are separated into multiple structs as a memory saving measure: 132 * - Common fields struct, always defined, and embedded within it: 133 * - L2-only fields, always allocated but undefined when not in L2ARC 134 * - L1-only fields, only allocated when in L1ARC 135 * 136 * Buffer in L1 Buffer only in L2 137 * +------------------------+ +------------------------+ 138 * | arc_buf_hdr_t | | arc_buf_hdr_t | 139 * | | | | 140 * | | | | 141 * | | | | 142 * +------------------------+ +------------------------+ 143 * | l2arc_buf_hdr_t | | l2arc_buf_hdr_t | 144 * | (undefined if L1-only) | | | 145 * +------------------------+ +------------------------+ 146 * | l1arc_buf_hdr_t | 147 * | | 148 * | | 149 * | | 150 * | | 151 * +------------------------+ 152 * 153 * Because it's possible for the L2ARC to become extremely large, we can wind 154 * up eating a lot of memory in L2ARC buffer headers, so the size of a header 155 * is minimized by only allocating the fields necessary for an L1-cached buffer 156 * when a header is actually in the L1 cache. The sub-headers (l1arc_buf_hdr and 157 * l2arc_buf_hdr) are embedded rather than allocated separately to save a couple 158 * words in pointers. arc_hdr_realloc() is used to switch a header between 159 * these two allocation states. 160 */ 161 typedef struct l1arc_buf_hdr { 162 /* protected by arc state mutex */ 163 arc_state_t *b_state; 164 multilist_node_t b_arc_node; 165 166 /* protected by hash lock */ 167 clock_t b_arc_access; 168 uint32_t b_mru_hits; 169 uint32_t b_mru_ghost_hits; 170 uint32_t b_mfu_hits; 171 uint32_t b_mfu_ghost_hits; 172 uint8_t b_byteswap; 173 arc_buf_t *b_buf; 174 175 /* self protecting */ 176 zfs_refcount_t b_refcnt; 177 178 arc_callback_t *b_acb; 179 abd_t *b_pabd; 180 181 #ifdef ZFS_DEBUG 182 zio_cksum_t *b_freeze_cksum; 183 kmutex_t b_freeze_lock; 184 #endif 185 } l1arc_buf_hdr_t; 186 187 typedef enum l2arc_dev_hdr_flags_t { 188 L2ARC_DEV_HDR_EVICT_FIRST = (1 << 0) /* mirror of l2ad_first */ 189 } l2arc_dev_hdr_flags_t; 190 191 /* 192 * Pointer used in persistent L2ARC (for pointing to log blocks). 193 */ 194 typedef struct l2arc_log_blkptr { 195 /* 196 * Offset of log block within the device, in bytes 197 */ 198 uint64_t lbp_daddr; 199 /* 200 * Aligned payload size (in bytes) of the log block 201 */ 202 uint64_t lbp_payload_asize; 203 /* 204 * Offset in bytes of the first buffer in the payload 205 */ 206 uint64_t lbp_payload_start; 207 /* 208 * lbp_prop has the following format: 209 * * logical size (in bytes) 210 * * aligned (after compression) size (in bytes) 211 * * compression algorithm (we always LZ4-compress l2arc logs) 212 * * checksum algorithm (used for lbp_cksum) 213 */ 214 uint64_t lbp_prop; 215 zio_cksum_t lbp_cksum; /* checksum of log */ 216 } l2arc_log_blkptr_t; 217 218 /* 219 * The persistent L2ARC device header. 220 * Byte order of magic determines whether 64-bit bswap of fields is necessary. 221 */ 222 typedef struct l2arc_dev_hdr_phys { 223 uint64_t dh_magic; /* L2ARC_DEV_HDR_MAGIC */ 224 uint64_t dh_version; /* Persistent L2ARC version */ 225 226 /* 227 * Global L2ARC device state and metadata. 228 */ 229 uint64_t dh_spa_guid; 230 uint64_t dh_vdev_guid; 231 uint64_t dh_log_entries; /* mirror of l2ad_log_entries */ 232 uint64_t dh_evict; /* evicted offset in bytes */ 233 uint64_t dh_flags; /* l2arc_dev_hdr_flags_t */ 234 /* 235 * Used in zdb.c for determining if a log block is valid, in the same 236 * way that l2arc_rebuild() does. 237 */ 238 uint64_t dh_start; /* mirror of l2ad_start */ 239 uint64_t dh_end; /* mirror of l2ad_end */ 240 /* 241 * Start of log block chain. [0] -> newest log, [1] -> one older (used 242 * for initiating prefetch). 243 */ 244 l2arc_log_blkptr_t dh_start_lbps[2]; 245 /* 246 * Aligned size of all log blocks as accounted by vdev_space_update(). 247 */ 248 uint64_t dh_lb_asize; /* mirror of l2ad_lb_asize */ 249 uint64_t dh_lb_count; /* mirror of l2ad_lb_count */ 250 /* 251 * Mirrors of vdev_trim_action_time and vdev_trim_state, used to 252 * display when the cache device was fully trimmed for the last 253 * time. 254 */ 255 uint64_t dh_trim_action_time; 256 uint64_t dh_trim_state; 257 const uint64_t dh_pad[30]; /* pad to 512 bytes */ 258 zio_eck_t dh_tail; 259 } l2arc_dev_hdr_phys_t; 260 _Static_assert(sizeof (l2arc_dev_hdr_phys_t) == SPA_MINBLOCKSIZE, 261 "l2arc_dev_hdr_phys_t wrong size"); 262 263 /* 264 * A single ARC buffer header entry in a l2arc_log_blk_phys_t. 265 */ 266 typedef struct l2arc_log_ent_phys { 267 dva_t le_dva; /* dva of buffer */ 268 uint64_t le_birth; /* birth txg of buffer */ 269 /* 270 * le_prop has the following format: 271 * * logical size (in bytes) 272 * * physical (compressed) size (in bytes) 273 * * compression algorithm 274 * * object type (used to restore arc_buf_contents_t) 275 * * protected status (used for encryption) 276 * * prefetch status (used in l2arc_read_done()) 277 */ 278 uint64_t le_prop; 279 uint64_t le_daddr; /* buf location on l2dev */ 280 uint64_t le_complevel; 281 /* 282 * We pad the size of each entry to a power of 2 so that the size of 283 * l2arc_log_blk_phys_t is power-of-2 aligned with SPA_MINBLOCKSHIFT, 284 * because of the L2ARC_SET_*SIZE macros. 285 */ 286 const uint64_t le_pad[2]; /* pad to 64 bytes */ 287 } l2arc_log_ent_phys_t; 288 289 #define L2ARC_LOG_BLK_MAX_ENTRIES (1022) 290 291 /* 292 * A log block of up to 1022 ARC buffer log entries, chained into the 293 * persistent L2ARC metadata linked list. Byte order of magic determines 294 * whether 64-bit bswap of fields is necessary. 295 */ 296 typedef struct l2arc_log_blk_phys { 297 uint64_t lb_magic; /* L2ARC_LOG_BLK_MAGIC */ 298 /* 299 * There are 2 chains (headed by dh_start_lbps[2]), and this field 300 * points back to the previous block in this chain. We alternate 301 * which chain we append to, so they are time-wise and offset-wise 302 * interleaved, but that is an optimization rather than for 303 * correctness. 304 */ 305 l2arc_log_blkptr_t lb_prev_lbp; /* pointer to prev log block */ 306 /* 307 * Pad header section to 128 bytes 308 */ 309 uint64_t lb_pad[7]; 310 /* Payload */ 311 l2arc_log_ent_phys_t lb_entries[L2ARC_LOG_BLK_MAX_ENTRIES]; 312 } l2arc_log_blk_phys_t; /* 64K total */ 313 314 /* 315 * The size of l2arc_log_blk_phys_t has to be power-of-2 aligned with 316 * SPA_MINBLOCKSHIFT because of L2BLK_SET_*SIZE macros. 317 */ 318 _Static_assert(IS_P2ALIGNED(sizeof (l2arc_log_blk_phys_t), 319 1ULL << SPA_MINBLOCKSHIFT), "l2arc_log_blk_phys_t misaligned"); 320 _Static_assert(sizeof (l2arc_log_blk_phys_t) >= SPA_MINBLOCKSIZE, 321 "l2arc_log_blk_phys_t too small"); 322 _Static_assert(sizeof (l2arc_log_blk_phys_t) <= SPA_MAXBLOCKSIZE, 323 "l2arc_log_blk_phys_t too big"); 324 325 /* 326 * These structures hold in-flight abd buffers for log blocks as they're being 327 * written to the L2ARC device. 328 */ 329 typedef struct l2arc_lb_abd_buf { 330 abd_t *abd; 331 list_node_t node; 332 } l2arc_lb_abd_buf_t; 333 334 /* 335 * These structures hold pointers to log blocks present on the L2ARC device. 336 */ 337 typedef struct l2arc_lb_ptr_buf { 338 l2arc_log_blkptr_t *lb_ptr; 339 list_node_t node; 340 } l2arc_lb_ptr_buf_t; 341 342 /* Macros for setting fields in le_prop and lbp_prop */ 343 #define L2BLK_GET_LSIZE(field) \ 344 BF64_GET_SB((field), 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1) 345 #define L2BLK_SET_LSIZE(field, x) \ 346 BF64_SET_SB((field), 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x) 347 #define L2BLK_GET_PSIZE(field) \ 348 BF64_GET_SB((field), 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1) 349 #define L2BLK_SET_PSIZE(field, x) \ 350 BF64_SET_SB((field), 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1, x) 351 #define L2BLK_GET_COMPRESS(field) \ 352 BF64_GET((field), 32, SPA_COMPRESSBITS) 353 #define L2BLK_SET_COMPRESS(field, x) \ 354 BF64_SET((field), 32, SPA_COMPRESSBITS, x) 355 #define L2BLK_GET_PREFETCH(field) BF64_GET((field), 39, 1) 356 #define L2BLK_SET_PREFETCH(field, x) BF64_SET((field), 39, 1, x) 357 #define L2BLK_GET_CHECKSUM(field) BF64_GET((field), 40, 8) 358 #define L2BLK_SET_CHECKSUM(field, x) BF64_SET((field), 40, 8, x) 359 /* +/- 1 here are to keep compatibility after ARC_BUFC_INVALID removal. */ 360 #define L2BLK_GET_TYPE(field) (BF64_GET((field), 48, 8) - 1) 361 #define L2BLK_SET_TYPE(field, x) BF64_SET((field), 48, 8, (x) + 1) 362 #define L2BLK_GET_PROTECTED(field) BF64_GET((field), 56, 1) 363 #define L2BLK_SET_PROTECTED(field, x) BF64_SET((field), 56, 1, x) 364 #define L2BLK_GET_STATE(field) BF64_GET((field), 57, 4) 365 #define L2BLK_SET_STATE(field, x) BF64_SET((field), 57, 4, x) 366 367 #define PTR_SWAP(x, y) \ 368 do { \ 369 void *tmp = (x);\ 370 x = y; \ 371 y = tmp; \ 372 } while (0) 373 374 #define L2ARC_DEV_HDR_MAGIC 0x5a46534341434845LLU /* ASCII: "ZFSCACHE" */ 375 #define L2ARC_LOG_BLK_MAGIC 0x4c4f47424c4b4844LLU /* ASCII: "LOGBLKHD" */ 376 377 /* 378 * L2ARC Internals 379 */ 380 typedef struct l2arc_dev { 381 vdev_t *l2ad_vdev; /* vdev */ 382 spa_t *l2ad_spa; /* spa */ 383 uint64_t l2ad_hand; /* next write location */ 384 uint64_t l2ad_start; /* first addr on device */ 385 uint64_t l2ad_end; /* last addr on device */ 386 boolean_t l2ad_first; /* first sweep through */ 387 boolean_t l2ad_writing; /* currently writing */ 388 kmutex_t l2ad_mtx; /* lock for buffer list */ 389 list_t l2ad_buflist; /* buffer list */ 390 list_node_t l2ad_node; /* device list node */ 391 zfs_refcount_t l2ad_alloc; /* allocated bytes */ 392 /* 393 * Persistence-related stuff 394 */ 395 l2arc_dev_hdr_phys_t *l2ad_dev_hdr; /* persistent device header */ 396 uint64_t l2ad_dev_hdr_asize; /* aligned hdr size */ 397 l2arc_log_blk_phys_t l2ad_log_blk; /* currently open log block */ 398 int l2ad_log_ent_idx; /* index into cur log blk */ 399 /* Number of bytes in current log block's payload */ 400 uint64_t l2ad_log_blk_payload_asize; 401 /* 402 * Offset (in bytes) of the first buffer in current log block's 403 * payload. 404 */ 405 uint64_t l2ad_log_blk_payload_start; 406 /* Flag indicating whether a rebuild is scheduled or is going on */ 407 boolean_t l2ad_rebuild; 408 boolean_t l2ad_rebuild_cancel; 409 boolean_t l2ad_rebuild_began; 410 uint64_t l2ad_log_entries; /* entries per log blk */ 411 uint64_t l2ad_evict; /* evicted offset in bytes */ 412 /* List of pointers to log blocks present in the L2ARC device */ 413 list_t l2ad_lbptr_list; 414 /* 415 * Aligned size of all log blocks as accounted by vdev_space_update(). 416 */ 417 zfs_refcount_t l2ad_lb_asize; 418 /* 419 * Number of log blocks present on the device. 420 */ 421 zfs_refcount_t l2ad_lb_count; 422 boolean_t l2ad_trim_all; /* TRIM whole device */ 423 } l2arc_dev_t; 424 425 /* 426 * Encrypted blocks will need to be stored encrypted on the L2ARC 427 * disk as they appear in the main pool. In order for this to work we 428 * need to pass around the encryption parameters so they can be used 429 * to write data to the L2ARC. This struct is only defined in the 430 * arc_buf_hdr_t if the L1 header is defined and has the ARC_FLAG_ENCRYPTED 431 * flag set. 432 */ 433 typedef struct arc_buf_hdr_crypt { 434 abd_t *b_rabd; /* raw encrypted data */ 435 436 /* dsobj for looking up encryption key for l2arc encryption */ 437 uint64_t b_dsobj; 438 439 dmu_object_type_t b_ot; /* object type */ 440 441 /* encryption parameters */ 442 uint8_t b_salt[ZIO_DATA_SALT_LEN]; 443 uint8_t b_iv[ZIO_DATA_IV_LEN]; 444 445 /* 446 * Technically this could be removed since we will always be able to 447 * get the mac from the bp when we need it. However, it is inconvenient 448 * for callers of arc code to have to pass a bp in all the time. This 449 * also allows us to assert that L2ARC data is properly encrypted to 450 * match the data in the main storage pool. 451 */ 452 uint8_t b_mac[ZIO_DATA_MAC_LEN]; 453 } arc_buf_hdr_crypt_t; 454 455 typedef struct l2arc_buf_hdr { 456 /* protected by arc_buf_hdr mutex */ 457 l2arc_dev_t *b_dev; /* L2ARC device */ 458 uint64_t b_daddr; /* disk address, offset byte */ 459 uint32_t b_hits; 460 arc_state_type_t b_arcs_state; 461 list_node_t b_l2node; 462 } l2arc_buf_hdr_t; 463 464 typedef struct l2arc_write_callback { 465 l2arc_dev_t *l2wcb_dev; /* device info */ 466 arc_buf_hdr_t *l2wcb_head; /* head of write buflist */ 467 /* in-flight list of log blocks */ 468 list_t l2wcb_abd_list; 469 } l2arc_write_callback_t; 470 471 struct arc_buf_hdr { 472 /* protected by hash lock */ 473 dva_t b_dva; 474 uint64_t b_birth; 475 476 arc_buf_contents_t b_type; 477 uint8_t b_complevel; 478 uint8_t b_reserved1; /* used for 4 byte alignment */ 479 uint16_t b_reserved2; /* used for 4 byte alignment */ 480 arc_buf_hdr_t *b_hash_next; 481 arc_flags_t b_flags; 482 483 /* 484 * This field stores the size of the data buffer after 485 * compression, and is set in the arc's zio completion handlers. 486 * It is in units of SPA_MINBLOCKSIZE (e.g. 1 == 512 bytes). 487 * 488 * While the block pointers can store up to 32MB in their psize 489 * field, we can only store up to 32MB minus 512B. This is due 490 * to the bp using a bias of 1, whereas we use a bias of 0 (i.e. 491 * a field of zeros represents 512B in the bp). We can't use a 492 * bias of 1 since we need to reserve a psize of zero, here, to 493 * represent holes and embedded blocks. 494 * 495 * This isn't a problem in practice, since the maximum size of a 496 * buffer is limited to 16MB, so we never need to store 32MB in 497 * this field. Even in the upstream illumos code base, the 498 * maximum size of a buffer is limited to 16MB. 499 */ 500 uint16_t b_psize; 501 502 /* 503 * This field stores the size of the data buffer before 504 * compression, and cannot change once set. It is in units 505 * of SPA_MINBLOCKSIZE (e.g. 2 == 1024 bytes) 506 */ 507 uint16_t b_lsize; /* immutable */ 508 uint64_t b_spa; /* immutable */ 509 510 /* L2ARC fields. Undefined when not in L2ARC. */ 511 l2arc_buf_hdr_t b_l2hdr; 512 /* L1ARC fields. Undefined when in l2arc_only state */ 513 l1arc_buf_hdr_t b_l1hdr; 514 /* 515 * Encryption parameters. Defined only when ARC_FLAG_ENCRYPTED 516 * is set and the L1 header exists. 517 */ 518 arc_buf_hdr_crypt_t b_crypt_hdr; 519 }; 520 521 typedef struct arc_stats { 522 /* Number of requests that were satisfied without I/O. */ 523 kstat_named_t arcstat_hits; 524 /* Number of requests for which I/O was already running. */ 525 kstat_named_t arcstat_iohits; 526 /* Number of requests for which I/O has to be issued. */ 527 kstat_named_t arcstat_misses; 528 /* Same three, but specifically for demand data. */ 529 kstat_named_t arcstat_demand_data_hits; 530 kstat_named_t arcstat_demand_data_iohits; 531 kstat_named_t arcstat_demand_data_misses; 532 /* Same three, but specifically for demand metadata. */ 533 kstat_named_t arcstat_demand_metadata_hits; 534 kstat_named_t arcstat_demand_metadata_iohits; 535 kstat_named_t arcstat_demand_metadata_misses; 536 /* Same three, but specifically for prefetch data. */ 537 kstat_named_t arcstat_prefetch_data_hits; 538 kstat_named_t arcstat_prefetch_data_iohits; 539 kstat_named_t arcstat_prefetch_data_misses; 540 /* Same three, but specifically for prefetch metadata. */ 541 kstat_named_t arcstat_prefetch_metadata_hits; 542 kstat_named_t arcstat_prefetch_metadata_iohits; 543 kstat_named_t arcstat_prefetch_metadata_misses; 544 kstat_named_t arcstat_mru_hits; 545 kstat_named_t arcstat_mru_ghost_hits; 546 kstat_named_t arcstat_mfu_hits; 547 kstat_named_t arcstat_mfu_ghost_hits; 548 kstat_named_t arcstat_uncached_hits; 549 kstat_named_t arcstat_deleted; 550 /* 551 * Number of buffers that could not be evicted because the hash lock 552 * was held by another thread. The lock may not necessarily be held 553 * by something using the same buffer, since hash locks are shared 554 * by multiple buffers. 555 */ 556 kstat_named_t arcstat_mutex_miss; 557 /* 558 * Number of buffers skipped when updating the access state due to the 559 * header having already been released after acquiring the hash lock. 560 */ 561 kstat_named_t arcstat_access_skip; 562 /* 563 * Number of buffers skipped because they have I/O in progress, are 564 * indirect prefetch buffers that have not lived long enough, or are 565 * not from the spa we're trying to evict from. 566 */ 567 kstat_named_t arcstat_evict_skip; 568 /* 569 * Number of times arc_evict_state() was unable to evict enough 570 * buffers to reach its target amount. 571 */ 572 kstat_named_t arcstat_evict_not_enough; 573 kstat_named_t arcstat_evict_l2_cached; 574 kstat_named_t arcstat_evict_l2_eligible; 575 kstat_named_t arcstat_evict_l2_eligible_mfu; 576 kstat_named_t arcstat_evict_l2_eligible_mru; 577 kstat_named_t arcstat_evict_l2_ineligible; 578 kstat_named_t arcstat_evict_l2_skip; 579 kstat_named_t arcstat_hash_elements; 580 kstat_named_t arcstat_hash_elements_max; 581 kstat_named_t arcstat_hash_collisions; 582 kstat_named_t arcstat_hash_chains; 583 kstat_named_t arcstat_hash_chain_max; 584 kstat_named_t arcstat_meta; 585 kstat_named_t arcstat_pd; 586 kstat_named_t arcstat_pm; 587 kstat_named_t arcstat_c; 588 kstat_named_t arcstat_c_min; 589 kstat_named_t arcstat_c_max; 590 kstat_named_t arcstat_size; 591 /* 592 * Number of compressed bytes stored in the arc_buf_hdr_t's b_pabd. 593 * Note that the compressed bytes may match the uncompressed bytes 594 * if the block is either not compressed or compressed arc is disabled. 595 */ 596 kstat_named_t arcstat_compressed_size; 597 /* 598 * Uncompressed size of the data stored in b_pabd. If compressed 599 * arc is disabled then this value will be identical to the stat 600 * above. 601 */ 602 kstat_named_t arcstat_uncompressed_size; 603 /* 604 * Number of bytes stored in all the arc_buf_t's. This is classified 605 * as "overhead" since this data is typically short-lived and will 606 * be evicted from the arc when it becomes unreferenced unless the 607 * zfs_keep_uncompressed_metadata or zfs_keep_uncompressed_level 608 * values have been set (see comment in dbuf.c for more information). 609 */ 610 kstat_named_t arcstat_overhead_size; 611 /* 612 * Number of bytes consumed by internal ARC structures necessary 613 * for tracking purposes; these structures are not actually 614 * backed by ARC buffers. This includes arc_buf_hdr_t structures 615 * (allocated via arc_buf_hdr_t_full and arc_buf_hdr_t_l2only 616 * caches), and arc_buf_t structures (allocated via arc_buf_t 617 * cache). 618 */ 619 kstat_named_t arcstat_hdr_size; 620 /* 621 * Number of bytes consumed by ARC buffers of type equal to 622 * ARC_BUFC_DATA. This is generally consumed by buffers backing 623 * on disk user data (e.g. plain file contents). 624 */ 625 kstat_named_t arcstat_data_size; 626 /* 627 * Number of bytes consumed by ARC buffers of type equal to 628 * ARC_BUFC_METADATA. This is generally consumed by buffers 629 * backing on disk data that is used for internal ZFS 630 * structures (e.g. ZAP, dnode, indirect blocks, etc). 631 */ 632 kstat_named_t arcstat_metadata_size; 633 /* 634 * Number of bytes consumed by dmu_buf_impl_t objects. 635 */ 636 kstat_named_t arcstat_dbuf_size; 637 /* 638 * Number of bytes consumed by dnode_t objects. 639 */ 640 kstat_named_t arcstat_dnode_size; 641 /* 642 * Number of bytes consumed by bonus buffers. 643 */ 644 kstat_named_t arcstat_bonus_size; 645 #if defined(COMPAT_FREEBSD11) 646 /* 647 * Sum of the previous three counters, provided for compatibility. 648 */ 649 kstat_named_t arcstat_other_size; 650 #endif 651 652 /* 653 * Total number of bytes consumed by ARC buffers residing in the 654 * arc_anon state. This includes *all* buffers in the arc_anon 655 * state; e.g. data, metadata, evictable, and unevictable buffers 656 * are all included in this value. 657 */ 658 kstat_named_t arcstat_anon_size; 659 kstat_named_t arcstat_anon_data; 660 kstat_named_t arcstat_anon_metadata; 661 /* 662 * Number of bytes consumed by ARC buffers that meet the 663 * following criteria: backing buffers of type ARC_BUFC_DATA, 664 * residing in the arc_anon state, and are eligible for eviction 665 * (e.g. have no outstanding holds on the buffer). 666 */ 667 kstat_named_t arcstat_anon_evictable_data; 668 /* 669 * Number of bytes consumed by ARC buffers that meet the 670 * following criteria: backing buffers of type ARC_BUFC_METADATA, 671 * residing in the arc_anon state, and are eligible for eviction 672 * (e.g. have no outstanding holds on the buffer). 673 */ 674 kstat_named_t arcstat_anon_evictable_metadata; 675 /* 676 * Total number of bytes consumed by ARC buffers residing in the 677 * arc_mru state. This includes *all* buffers in the arc_mru 678 * state; e.g. data, metadata, evictable, and unevictable buffers 679 * are all included in this value. 680 */ 681 kstat_named_t arcstat_mru_size; 682 kstat_named_t arcstat_mru_data; 683 kstat_named_t arcstat_mru_metadata; 684 /* 685 * Number of bytes consumed by ARC buffers that meet the 686 * following criteria: backing buffers of type ARC_BUFC_DATA, 687 * residing in the arc_mru state, and are eligible for eviction 688 * (e.g. have no outstanding holds on the buffer). 689 */ 690 kstat_named_t arcstat_mru_evictable_data; 691 /* 692 * Number of bytes consumed by ARC buffers that meet the 693 * following criteria: backing buffers of type ARC_BUFC_METADATA, 694 * residing in the arc_mru state, and are eligible for eviction 695 * (e.g. have no outstanding holds on the buffer). 696 */ 697 kstat_named_t arcstat_mru_evictable_metadata; 698 /* 699 * Total number of bytes that *would have been* consumed by ARC 700 * buffers in the arc_mru_ghost state. The key thing to note 701 * here, is the fact that this size doesn't actually indicate 702 * RAM consumption. The ghost lists only consist of headers and 703 * don't actually have ARC buffers linked off of these headers. 704 * Thus, *if* the headers had associated ARC buffers, these 705 * buffers *would have* consumed this number of bytes. 706 */ 707 kstat_named_t arcstat_mru_ghost_size; 708 kstat_named_t arcstat_mru_ghost_data; 709 kstat_named_t arcstat_mru_ghost_metadata; 710 /* 711 * Number of bytes that *would have been* consumed by ARC 712 * buffers that are eligible for eviction, of type 713 * ARC_BUFC_DATA, and linked off the arc_mru_ghost state. 714 */ 715 kstat_named_t arcstat_mru_ghost_evictable_data; 716 /* 717 * Number of bytes that *would have been* consumed by ARC 718 * buffers that are eligible for eviction, of type 719 * ARC_BUFC_METADATA, and linked off the arc_mru_ghost state. 720 */ 721 kstat_named_t arcstat_mru_ghost_evictable_metadata; 722 /* 723 * Total number of bytes consumed by ARC buffers residing in the 724 * arc_mfu state. This includes *all* buffers in the arc_mfu 725 * state; e.g. data, metadata, evictable, and unevictable buffers 726 * are all included in this value. 727 */ 728 kstat_named_t arcstat_mfu_size; 729 kstat_named_t arcstat_mfu_data; 730 kstat_named_t arcstat_mfu_metadata; 731 /* 732 * Number of bytes consumed by ARC buffers that are eligible for 733 * eviction, of type ARC_BUFC_DATA, and reside in the arc_mfu 734 * state. 735 */ 736 kstat_named_t arcstat_mfu_evictable_data; 737 /* 738 * Number of bytes consumed by ARC buffers that are eligible for 739 * eviction, of type ARC_BUFC_METADATA, and reside in the 740 * arc_mfu state. 741 */ 742 kstat_named_t arcstat_mfu_evictable_metadata; 743 /* 744 * Total number of bytes that *would have been* consumed by ARC 745 * buffers in the arc_mfu_ghost state. See the comment above 746 * arcstat_mru_ghost_size for more details. 747 */ 748 kstat_named_t arcstat_mfu_ghost_size; 749 kstat_named_t arcstat_mfu_ghost_data; 750 kstat_named_t arcstat_mfu_ghost_metadata; 751 /* 752 * Number of bytes that *would have been* consumed by ARC 753 * buffers that are eligible for eviction, of type 754 * ARC_BUFC_DATA, and linked off the arc_mfu_ghost state. 755 */ 756 kstat_named_t arcstat_mfu_ghost_evictable_data; 757 /* 758 * Number of bytes that *would have been* consumed by ARC 759 * buffers that are eligible for eviction, of type 760 * ARC_BUFC_METADATA, and linked off the arc_mru_ghost state. 761 */ 762 kstat_named_t arcstat_mfu_ghost_evictable_metadata; 763 /* 764 * Total number of bytes that are going to be evicted from ARC due to 765 * ARC_FLAG_UNCACHED being set. 766 */ 767 kstat_named_t arcstat_uncached_size; 768 kstat_named_t arcstat_uncached_data; 769 kstat_named_t arcstat_uncached_metadata; 770 /* 771 * Number of data bytes that are going to be evicted from ARC due to 772 * ARC_FLAG_UNCACHED being set. 773 */ 774 kstat_named_t arcstat_uncached_evictable_data; 775 /* 776 * Number of metadata bytes that that are going to be evicted from ARC 777 * due to ARC_FLAG_UNCACHED being set. 778 */ 779 kstat_named_t arcstat_uncached_evictable_metadata; 780 kstat_named_t arcstat_l2_hits; 781 kstat_named_t arcstat_l2_misses; 782 /* 783 * Allocated size (in bytes) of L2ARC cached buffers by ARC state. 784 */ 785 kstat_named_t arcstat_l2_prefetch_asize; 786 kstat_named_t arcstat_l2_mru_asize; 787 kstat_named_t arcstat_l2_mfu_asize; 788 /* 789 * Allocated size (in bytes) of L2ARC cached buffers by buffer content 790 * type. 791 */ 792 kstat_named_t arcstat_l2_bufc_data_asize; 793 kstat_named_t arcstat_l2_bufc_metadata_asize; 794 kstat_named_t arcstat_l2_feeds; 795 kstat_named_t arcstat_l2_rw_clash; 796 kstat_named_t arcstat_l2_read_bytes; 797 kstat_named_t arcstat_l2_write_bytes; 798 kstat_named_t arcstat_l2_writes_sent; 799 kstat_named_t arcstat_l2_writes_done; 800 kstat_named_t arcstat_l2_writes_error; 801 kstat_named_t arcstat_l2_writes_lock_retry; 802 kstat_named_t arcstat_l2_evict_lock_retry; 803 kstat_named_t arcstat_l2_evict_reading; 804 kstat_named_t arcstat_l2_evict_l1cached; 805 kstat_named_t arcstat_l2_free_on_write; 806 kstat_named_t arcstat_l2_abort_lowmem; 807 kstat_named_t arcstat_l2_cksum_bad; 808 kstat_named_t arcstat_l2_io_error; 809 kstat_named_t arcstat_l2_lsize; 810 kstat_named_t arcstat_l2_psize; 811 kstat_named_t arcstat_l2_hdr_size; 812 /* 813 * Number of L2ARC log blocks written. These are used for restoring the 814 * L2ARC. Updated during writing of L2ARC log blocks. 815 */ 816 kstat_named_t arcstat_l2_log_blk_writes; 817 /* 818 * Moving average of the aligned size of the L2ARC log blocks, in 819 * bytes. Updated during L2ARC rebuild and during writing of L2ARC 820 * log blocks. 821 */ 822 kstat_named_t arcstat_l2_log_blk_avg_asize; 823 /* Aligned size of L2ARC log blocks on L2ARC devices. */ 824 kstat_named_t arcstat_l2_log_blk_asize; 825 /* Number of L2ARC log blocks present on L2ARC devices. */ 826 kstat_named_t arcstat_l2_log_blk_count; 827 /* 828 * Moving average of the aligned size of L2ARC restored data, in bytes, 829 * to the aligned size of their metadata in L2ARC, in bytes. 830 * Updated during L2ARC rebuild and during writing of L2ARC log blocks. 831 */ 832 kstat_named_t arcstat_l2_data_to_meta_ratio; 833 /* 834 * Number of times the L2ARC rebuild was successful for an L2ARC device. 835 */ 836 kstat_named_t arcstat_l2_rebuild_success; 837 /* 838 * Number of times the L2ARC rebuild failed because the device header 839 * was in an unsupported format or corrupted. 840 */ 841 kstat_named_t arcstat_l2_rebuild_abort_unsupported; 842 /* 843 * Number of times the L2ARC rebuild failed because of IO errors 844 * while reading a log block. 845 */ 846 kstat_named_t arcstat_l2_rebuild_abort_io_errors; 847 /* 848 * Number of times the L2ARC rebuild failed because of IO errors when 849 * reading the device header. 850 */ 851 kstat_named_t arcstat_l2_rebuild_abort_dh_errors; 852 /* 853 * Number of L2ARC log blocks which failed to be restored due to 854 * checksum errors. 855 */ 856 kstat_named_t arcstat_l2_rebuild_abort_cksum_lb_errors; 857 /* 858 * Number of times the L2ARC rebuild was aborted due to low system 859 * memory. 860 */ 861 kstat_named_t arcstat_l2_rebuild_abort_lowmem; 862 /* Logical size of L2ARC restored data, in bytes. */ 863 kstat_named_t arcstat_l2_rebuild_size; 864 /* Aligned size of L2ARC restored data, in bytes. */ 865 kstat_named_t arcstat_l2_rebuild_asize; 866 /* 867 * Number of L2ARC log entries (buffers) that were successfully 868 * restored in ARC. 869 */ 870 kstat_named_t arcstat_l2_rebuild_bufs; 871 /* 872 * Number of L2ARC log entries (buffers) already cached in ARC. These 873 * were not restored again. 874 */ 875 kstat_named_t arcstat_l2_rebuild_bufs_precached; 876 /* 877 * Number of L2ARC log blocks that were restored successfully. Each 878 * log block may hold up to L2ARC_LOG_BLK_MAX_ENTRIES buffers. 879 */ 880 kstat_named_t arcstat_l2_rebuild_log_blks; 881 kstat_named_t arcstat_memory_throttle_count; 882 kstat_named_t arcstat_memory_direct_count; 883 kstat_named_t arcstat_memory_indirect_count; 884 kstat_named_t arcstat_memory_all_bytes; 885 kstat_named_t arcstat_memory_free_bytes; 886 kstat_named_t arcstat_memory_available_bytes; 887 kstat_named_t arcstat_no_grow; 888 kstat_named_t arcstat_tempreserve; 889 kstat_named_t arcstat_loaned_bytes; 890 kstat_named_t arcstat_prune; 891 kstat_named_t arcstat_meta_used; 892 kstat_named_t arcstat_dnode_limit; 893 kstat_named_t arcstat_async_upgrade_sync; 894 /* Number of predictive prefetch requests. */ 895 kstat_named_t arcstat_predictive_prefetch; 896 /* Number of requests for which predictive prefetch has completed. */ 897 kstat_named_t arcstat_demand_hit_predictive_prefetch; 898 /* Number of requests for which predictive prefetch was running. */ 899 kstat_named_t arcstat_demand_iohit_predictive_prefetch; 900 /* Number of prescient prefetch requests. */ 901 kstat_named_t arcstat_prescient_prefetch; 902 /* Number of requests for which prescient prefetch has completed. */ 903 kstat_named_t arcstat_demand_hit_prescient_prefetch; 904 /* Number of requests for which prescient prefetch was running. */ 905 kstat_named_t arcstat_demand_iohit_prescient_prefetch; 906 kstat_named_t arcstat_need_free; 907 kstat_named_t arcstat_sys_free; 908 kstat_named_t arcstat_raw_size; 909 kstat_named_t arcstat_cached_only_in_progress; 910 kstat_named_t arcstat_abd_chunk_waste_size; 911 } arc_stats_t; 912 913 typedef struct arc_sums { 914 wmsum_t arcstat_hits; 915 wmsum_t arcstat_iohits; 916 wmsum_t arcstat_misses; 917 wmsum_t arcstat_demand_data_hits; 918 wmsum_t arcstat_demand_data_iohits; 919 wmsum_t arcstat_demand_data_misses; 920 wmsum_t arcstat_demand_metadata_hits; 921 wmsum_t arcstat_demand_metadata_iohits; 922 wmsum_t arcstat_demand_metadata_misses; 923 wmsum_t arcstat_prefetch_data_hits; 924 wmsum_t arcstat_prefetch_data_iohits; 925 wmsum_t arcstat_prefetch_data_misses; 926 wmsum_t arcstat_prefetch_metadata_hits; 927 wmsum_t arcstat_prefetch_metadata_iohits; 928 wmsum_t arcstat_prefetch_metadata_misses; 929 wmsum_t arcstat_mru_hits; 930 wmsum_t arcstat_mru_ghost_hits; 931 wmsum_t arcstat_mfu_hits; 932 wmsum_t arcstat_mfu_ghost_hits; 933 wmsum_t arcstat_uncached_hits; 934 wmsum_t arcstat_deleted; 935 wmsum_t arcstat_mutex_miss; 936 wmsum_t arcstat_access_skip; 937 wmsum_t arcstat_evict_skip; 938 wmsum_t arcstat_evict_not_enough; 939 wmsum_t arcstat_evict_l2_cached; 940 wmsum_t arcstat_evict_l2_eligible; 941 wmsum_t arcstat_evict_l2_eligible_mfu; 942 wmsum_t arcstat_evict_l2_eligible_mru; 943 wmsum_t arcstat_evict_l2_ineligible; 944 wmsum_t arcstat_evict_l2_skip; 945 wmsum_t arcstat_hash_collisions; 946 wmsum_t arcstat_hash_chains; 947 aggsum_t arcstat_size; 948 wmsum_t arcstat_compressed_size; 949 wmsum_t arcstat_uncompressed_size; 950 wmsum_t arcstat_overhead_size; 951 wmsum_t arcstat_hdr_size; 952 wmsum_t arcstat_data_size; 953 wmsum_t arcstat_metadata_size; 954 wmsum_t arcstat_dbuf_size; 955 wmsum_t arcstat_dnode_size; 956 wmsum_t arcstat_bonus_size; 957 wmsum_t arcstat_l2_hits; 958 wmsum_t arcstat_l2_misses; 959 wmsum_t arcstat_l2_prefetch_asize; 960 wmsum_t arcstat_l2_mru_asize; 961 wmsum_t arcstat_l2_mfu_asize; 962 wmsum_t arcstat_l2_bufc_data_asize; 963 wmsum_t arcstat_l2_bufc_metadata_asize; 964 wmsum_t arcstat_l2_feeds; 965 wmsum_t arcstat_l2_rw_clash; 966 wmsum_t arcstat_l2_read_bytes; 967 wmsum_t arcstat_l2_write_bytes; 968 wmsum_t arcstat_l2_writes_sent; 969 wmsum_t arcstat_l2_writes_done; 970 wmsum_t arcstat_l2_writes_error; 971 wmsum_t arcstat_l2_writes_lock_retry; 972 wmsum_t arcstat_l2_evict_lock_retry; 973 wmsum_t arcstat_l2_evict_reading; 974 wmsum_t arcstat_l2_evict_l1cached; 975 wmsum_t arcstat_l2_free_on_write; 976 wmsum_t arcstat_l2_abort_lowmem; 977 wmsum_t arcstat_l2_cksum_bad; 978 wmsum_t arcstat_l2_io_error; 979 wmsum_t arcstat_l2_lsize; 980 wmsum_t arcstat_l2_psize; 981 aggsum_t arcstat_l2_hdr_size; 982 wmsum_t arcstat_l2_log_blk_writes; 983 wmsum_t arcstat_l2_log_blk_asize; 984 wmsum_t arcstat_l2_log_blk_count; 985 wmsum_t arcstat_l2_rebuild_success; 986 wmsum_t arcstat_l2_rebuild_abort_unsupported; 987 wmsum_t arcstat_l2_rebuild_abort_io_errors; 988 wmsum_t arcstat_l2_rebuild_abort_dh_errors; 989 wmsum_t arcstat_l2_rebuild_abort_cksum_lb_errors; 990 wmsum_t arcstat_l2_rebuild_abort_lowmem; 991 wmsum_t arcstat_l2_rebuild_size; 992 wmsum_t arcstat_l2_rebuild_asize; 993 wmsum_t arcstat_l2_rebuild_bufs; 994 wmsum_t arcstat_l2_rebuild_bufs_precached; 995 wmsum_t arcstat_l2_rebuild_log_blks; 996 wmsum_t arcstat_memory_throttle_count; 997 wmsum_t arcstat_memory_direct_count; 998 wmsum_t arcstat_memory_indirect_count; 999 wmsum_t arcstat_prune; 1000 wmsum_t arcstat_meta_used; 1001 wmsum_t arcstat_async_upgrade_sync; 1002 wmsum_t arcstat_predictive_prefetch; 1003 wmsum_t arcstat_demand_hit_predictive_prefetch; 1004 wmsum_t arcstat_demand_iohit_predictive_prefetch; 1005 wmsum_t arcstat_prescient_prefetch; 1006 wmsum_t arcstat_demand_hit_prescient_prefetch; 1007 wmsum_t arcstat_demand_iohit_prescient_prefetch; 1008 wmsum_t arcstat_raw_size; 1009 wmsum_t arcstat_cached_only_in_progress; 1010 wmsum_t arcstat_abd_chunk_waste_size; 1011 } arc_sums_t; 1012 1013 typedef struct arc_evict_waiter { 1014 list_node_t aew_node; 1015 kcondvar_t aew_cv; 1016 uint64_t aew_count; 1017 } arc_evict_waiter_t; 1018 1019 #define ARCSTAT(stat) (arc_stats.stat.value.ui64) 1020 1021 #define ARCSTAT_INCR(stat, val) \ 1022 wmsum_add(&arc_sums.stat, (val)) 1023 1024 #define ARCSTAT_BUMP(stat) ARCSTAT_INCR(stat, 1) 1025 #define ARCSTAT_BUMPDOWN(stat) ARCSTAT_INCR(stat, -1) 1026 1027 #define arc_no_grow ARCSTAT(arcstat_no_grow) /* do not grow cache size */ 1028 #define arc_meta ARCSTAT(arcstat_meta) /* target frac of metadata */ 1029 #define arc_pd ARCSTAT(arcstat_pd) /* target frac of data MRU */ 1030 #define arc_pm ARCSTAT(arcstat_pm) /* target frac of meta MRU */ 1031 #define arc_c ARCSTAT(arcstat_c) /* target size of cache */ 1032 #define arc_c_min ARCSTAT(arcstat_c_min) /* min target cache size */ 1033 #define arc_c_max ARCSTAT(arcstat_c_max) /* max target cache size */ 1034 #define arc_sys_free ARCSTAT(arcstat_sys_free) /* target system free bytes */ 1035 1036 #define arc_anon (&ARC_anon) 1037 #define arc_mru (&ARC_mru) 1038 #define arc_mru_ghost (&ARC_mru_ghost) 1039 #define arc_mfu (&ARC_mfu) 1040 #define arc_mfu_ghost (&ARC_mfu_ghost) 1041 #define arc_l2c_only (&ARC_l2c_only) 1042 #define arc_uncached (&ARC_uncached) 1043 1044 extern taskq_t *arc_prune_taskq; 1045 extern arc_stats_t arc_stats; 1046 extern arc_sums_t arc_sums; 1047 extern hrtime_t arc_growtime; 1048 extern boolean_t arc_warm; 1049 extern uint_t arc_grow_retry; 1050 extern uint_t arc_no_grow_shift; 1051 extern uint_t arc_shrink_shift; 1052 extern kmutex_t arc_prune_mtx; 1053 extern list_t arc_prune_list; 1054 extern arc_state_t ARC_mfu; 1055 extern arc_state_t ARC_mru; 1056 extern uint_t zfs_arc_pc_percent; 1057 extern uint_t arc_lotsfree_percent; 1058 extern uint64_t zfs_arc_min; 1059 extern uint64_t zfs_arc_max; 1060 1061 extern void arc_reduce_target_size(int64_t to_free); 1062 extern boolean_t arc_reclaim_needed(void); 1063 extern void arc_kmem_reap_soon(void); 1064 extern void arc_wait_for_eviction(uint64_t, boolean_t); 1065 1066 extern void arc_lowmem_init(void); 1067 extern void arc_lowmem_fini(void); 1068 extern int arc_memory_throttle(spa_t *spa, uint64_t reserve, uint64_t txg); 1069 extern uint64_t arc_free_memory(void); 1070 extern int64_t arc_available_memory(void); 1071 extern void arc_tuning_update(boolean_t); 1072 extern void arc_register_hotplug(void); 1073 extern void arc_unregister_hotplug(void); 1074 1075 extern int param_set_arc_u64(ZFS_MODULE_PARAM_ARGS); 1076 extern int param_set_arc_int(ZFS_MODULE_PARAM_ARGS); 1077 extern int param_set_arc_min(ZFS_MODULE_PARAM_ARGS); 1078 extern int param_set_arc_max(ZFS_MODULE_PARAM_ARGS); 1079 1080 /* used in zdb.c */ 1081 boolean_t l2arc_log_blkptr_valid(l2arc_dev_t *dev, 1082 const l2arc_log_blkptr_t *lbp); 1083 1084 /* used in vdev_trim.c */ 1085 void l2arc_dev_hdr_update(l2arc_dev_t *dev); 1086 l2arc_dev_t *l2arc_vdev_get(vdev_t *vd); 1087 1088 #ifdef __cplusplus 1089 } 1090 #endif 1091 1092 #endif /* _SYS_ARC_IMPL_H */ 1093