/* * CDDL HEADER START * * 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 usr/src/OPENSOLARIS.LICENSE * or http://www.opensolaris.org/os/licensing. * See the License for the specific language governing permissions * and limitations under the License. * * When distributing Covered Code, include this CDDL HEADER in each * file and include the License file at usr/src/OPENSOLARIS.LICENSE. * If applicable, add the following below this CDDL HEADER, with the * fields enclosed by brackets "[]" replaced with your own identifying * information: Portions Copyright [yyyy] [name of copyright owner] * * CDDL HEADER END */ /* * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved. * Copyright (c) 2013, Delphix. All rights reserved. * Copyright (c) 2013, Saso Kiselkov. All rights reserved. * Copyright (c) 2013, Nexenta Systems, Inc. All rights reserved. * Copyright (c) 2020, George Amanakis. All rights reserved. */ #ifndef _SYS_ARC_IMPL_H #define _SYS_ARC_IMPL_H #include #include #include #include #ifdef __cplusplus extern "C" { #endif /* * Note that buffers can be in one of 6 states: * ARC_anon - anonymous (discussed below) * ARC_mru - recently used, currently cached * ARC_mru_ghost - recently used, no longer in cache * ARC_mfu - frequently used, currently cached * ARC_mfu_ghost - frequently used, no longer in cache * ARC_l2c_only - exists in L2ARC but not other states * When there are no active references to the buffer, they are * are linked onto a list in one of these arc states. These are * the only buffers that can be evicted or deleted. Within each * state there are multiple lists, one for meta-data and one for * non-meta-data. Meta-data (indirect blocks, blocks of dnodes, * etc.) is tracked separately so that it can be managed more * explicitly: favored over data, limited explicitly. * * Anonymous buffers are buffers that are not associated with * a DVA. These are buffers that hold dirty block copies * before they are written to stable storage. By definition, * they are "ref'd" and are considered part of arc_mru * that cannot be freed. Generally, they will acquire a DVA * as they are written and migrate onto the arc_mru list. * * The ARC_l2c_only state is for buffers that are in the second * level ARC but no longer in any of the ARC_m* lists. The second * level ARC itself may also contain buffers that are in any of * the ARC_m* states - meaning that a buffer can exist in two * places. The reason for the ARC_l2c_only state is to keep the * buffer header in the hash table, so that reads that hit the * second level ARC benefit from these fast lookups. */ typedef struct arc_state { /* * list of evictable buffers */ multilist_t *arcs_list[ARC_BUFC_NUMTYPES]; /* * total amount of evictable data in this state */ zfs_refcount_t arcs_esize[ARC_BUFC_NUMTYPES]; /* * total amount of data in this state; this includes: evictable, * non-evictable, ARC_BUFC_DATA, and ARC_BUFC_METADATA. */ zfs_refcount_t arcs_size; /* * supports the "dbufs" kstat */ arc_state_type_t arcs_state; } arc_state_t; typedef struct arc_callback arc_callback_t; struct arc_callback { void *acb_private; arc_read_done_func_t *acb_done; arc_buf_t *acb_buf; boolean_t acb_encrypted; boolean_t acb_compressed; boolean_t acb_noauth; zbookmark_phys_t acb_zb; zio_t *acb_zio_dummy; zio_t *acb_zio_head; arc_callback_t *acb_next; }; typedef struct arc_write_callback arc_write_callback_t; struct arc_write_callback { void *awcb_private; arc_write_done_func_t *awcb_ready; arc_write_done_func_t *awcb_children_ready; arc_write_done_func_t *awcb_physdone; arc_write_done_func_t *awcb_done; arc_buf_t *awcb_buf; }; /* * ARC buffers are separated into multiple structs as a memory saving measure: * - Common fields struct, always defined, and embedded within it: * - L2-only fields, always allocated but undefined when not in L2ARC * - L1-only fields, only allocated when in L1ARC * * Buffer in L1 Buffer only in L2 * +------------------------+ +------------------------+ * | arc_buf_hdr_t | | arc_buf_hdr_t | * | | | | * | | | | * | | | | * +------------------------+ +------------------------+ * | l2arc_buf_hdr_t | | l2arc_buf_hdr_t | * | (undefined if L1-only) | | | * +------------------------+ +------------------------+ * | l1arc_buf_hdr_t | * | | * | | * | | * | | * +------------------------+ * * Because it's possible for the L2ARC to become extremely large, we can wind * up eating a lot of memory in L2ARC buffer headers, so the size of a header * is minimized by only allocating the fields necessary for an L1-cached buffer * when a header is actually in the L1 cache. The sub-headers (l1arc_buf_hdr and * l2arc_buf_hdr) are embedded rather than allocated separately to save a couple * words in pointers. arc_hdr_realloc() is used to switch a header between * these two allocation states. */ typedef struct l1arc_buf_hdr { kmutex_t b_freeze_lock; zio_cksum_t *b_freeze_cksum; arc_buf_t *b_buf; uint32_t b_bufcnt; /* for waiting on writes to complete */ kcondvar_t b_cv; uint8_t b_byteswap; /* protected by arc state mutex */ arc_state_t *b_state; multilist_node_t b_arc_node; /* updated atomically */ clock_t b_arc_access; uint32_t b_mru_hits; uint32_t b_mru_ghost_hits; uint32_t b_mfu_hits; uint32_t b_mfu_ghost_hits; uint32_t b_l2_hits; /* self protecting */ zfs_refcount_t b_refcnt; arc_callback_t *b_acb; abd_t *b_pabd; } l1arc_buf_hdr_t; typedef enum l2arc_dev_hdr_flags_t { L2ARC_DEV_HDR_EVICT_FIRST = (1 << 0) /* mirror of l2ad_first */ } l2arc_dev_hdr_flags_t; /* * Pointer used in persistent L2ARC (for pointing to log blocks). */ typedef struct l2arc_log_blkptr { /* * Offset of log block within the device, in bytes */ uint64_t lbp_daddr; /* * Aligned payload size (in bytes) of the log block */ uint64_t lbp_payload_asize; /* * Offset in bytes of the first buffer in the payload */ uint64_t lbp_payload_start; /* * lbp_prop has the following format: * * logical size (in bytes) * * aligned (after compression) size (in bytes) * * compression algorithm (we always LZ4-compress l2arc logs) * * checksum algorithm (used for lbp_cksum) */ uint64_t lbp_prop; zio_cksum_t lbp_cksum; /* checksum of log */ } l2arc_log_blkptr_t; /* * The persistent L2ARC device header. * Byte order of magic determines whether 64-bit bswap of fields is necessary. */ typedef struct l2arc_dev_hdr_phys { uint64_t dh_magic; /* L2ARC_DEV_HDR_MAGIC */ uint64_t dh_version; /* Persistent L2ARC version */ /* * Global L2ARC device state and metadata. */ uint64_t dh_spa_guid; uint64_t dh_vdev_guid; uint64_t dh_log_entries; /* mirror of l2ad_log_entries */ uint64_t dh_evict; /* evicted offset in bytes */ uint64_t dh_flags; /* l2arc_dev_hdr_flags_t */ /* * Used in zdb.c for determining if a log block is valid, in the same * way that l2arc_rebuild() does. */ uint64_t dh_start; /* mirror of l2ad_start */ uint64_t dh_end; /* mirror of l2ad_end */ /* * Start of log block chain. [0] -> newest log, [1] -> one older (used * for initiating prefetch). */ l2arc_log_blkptr_t dh_start_lbps[2]; /* * Aligned size of all log blocks as accounted by vdev_space_update(). */ uint64_t dh_lb_asize; /* mirror of l2ad_lb_asize */ uint64_t dh_lb_count; /* mirror of l2ad_lb_count */ /* * Mirrors of vdev_trim_action_time and vdev_trim_state, used to * display when the cache device was fully trimmed for the last * time. */ uint64_t dh_trim_action_time; uint64_t dh_trim_state; const uint64_t dh_pad[30]; /* pad to 512 bytes */ zio_eck_t dh_tail; } l2arc_dev_hdr_phys_t; CTASSERT_GLOBAL(sizeof (l2arc_dev_hdr_phys_t) == SPA_MINBLOCKSIZE); /* * A single ARC buffer header entry in a l2arc_log_blk_phys_t. */ typedef struct l2arc_log_ent_phys { dva_t le_dva; /* dva of buffer */ uint64_t le_birth; /* birth txg of buffer */ /* * le_prop has the following format: * * logical size (in bytes) * * physical (compressed) size (in bytes) * * compression algorithm * * object type (used to restore arc_buf_contents_t) * * protected status (used for encryption) * * prefetch status (used in l2arc_read_done()) */ uint64_t le_prop; uint64_t le_daddr; /* buf location on l2dev */ /* * We pad the size of each entry to a power of 2 so that the size of * l2arc_log_blk_phys_t is power-of-2 aligned with SPA_MINBLOCKSHIFT, * because of the L2ARC_SET_*SIZE macros. */ const uint64_t le_pad[3]; /* pad to 64 bytes */ } l2arc_log_ent_phys_t; #define L2ARC_LOG_BLK_MAX_ENTRIES (1022) /* * A log block of up to 1022 ARC buffer log entries, chained into the * persistent L2ARC metadata linked list. Byte order of magic determines * whether 64-bit bswap of fields is necessary. */ typedef struct l2arc_log_blk_phys { uint64_t lb_magic; /* L2ARC_LOG_BLK_MAGIC */ /* * There are 2 chains (headed by dh_start_lbps[2]), and this field * points back to the previous block in this chain. We alternate * which chain we append to, so they are time-wise and offset-wise * interleaved, but that is an optimization rather than for * correctness. */ l2arc_log_blkptr_t lb_prev_lbp; /* pointer to prev log block */ /* * Pad header section to 128 bytes */ uint64_t lb_pad[7]; /* Payload */ l2arc_log_ent_phys_t lb_entries[L2ARC_LOG_BLK_MAX_ENTRIES]; } l2arc_log_blk_phys_t; /* 64K total */ /* * The size of l2arc_log_blk_phys_t has to be power-of-2 aligned with * SPA_MINBLOCKSHIFT because of L2BLK_SET_*SIZE macros. */ CTASSERT_GLOBAL(IS_P2ALIGNED(sizeof (l2arc_log_blk_phys_t), 1ULL << SPA_MINBLOCKSHIFT)); CTASSERT_GLOBAL(sizeof (l2arc_log_blk_phys_t) >= SPA_MINBLOCKSIZE); CTASSERT_GLOBAL(sizeof (l2arc_log_blk_phys_t) <= SPA_MAXBLOCKSIZE); /* * These structures hold in-flight abd buffers for log blocks as they're being * written to the L2ARC device. */ typedef struct l2arc_lb_abd_buf { abd_t *abd; list_node_t node; } l2arc_lb_abd_buf_t; /* * These structures hold pointers to log blocks present on the L2ARC device. */ typedef struct l2arc_lb_ptr_buf { l2arc_log_blkptr_t *lb_ptr; list_node_t node; } l2arc_lb_ptr_buf_t; /* Macros for setting fields in le_prop and lbp_prop */ #define L2BLK_GET_LSIZE(field) \ BF64_GET_SB((field), 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1) #define L2BLK_SET_LSIZE(field, x) \ BF64_SET_SB((field), 0, SPA_LSIZEBITS, SPA_MINBLOCKSHIFT, 1, x) #define L2BLK_GET_PSIZE(field) \ BF64_GET_SB((field), 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1) #define L2BLK_SET_PSIZE(field, x) \ BF64_SET_SB((field), 16, SPA_PSIZEBITS, SPA_MINBLOCKSHIFT, 1, x) #define L2BLK_GET_COMPRESS(field) \ BF64_GET((field), 32, SPA_COMPRESSBITS) #define L2BLK_SET_COMPRESS(field, x) \ BF64_SET((field), 32, SPA_COMPRESSBITS, x) #define L2BLK_GET_PREFETCH(field) BF64_GET((field), 39, 1) #define L2BLK_SET_PREFETCH(field, x) BF64_SET((field), 39, 1, x) #define L2BLK_GET_CHECKSUM(field) BF64_GET((field), 40, 8) #define L2BLK_SET_CHECKSUM(field, x) BF64_SET((field), 40, 8, x) #define L2BLK_GET_TYPE(field) BF64_GET((field), 48, 8) #define L2BLK_SET_TYPE(field, x) BF64_SET((field), 48, 8, x) #define L2BLK_GET_PROTECTED(field) BF64_GET((field), 56, 1) #define L2BLK_SET_PROTECTED(field, x) BF64_SET((field), 56, 1, x) #define PTR_SWAP(x, y) \ do { \ void *tmp = (x);\ x = y; \ y = tmp; \ _NOTE(CONSTCOND)\ } while (0) #define L2ARC_DEV_HDR_MAGIC 0x5a46534341434845LLU /* ASCII: "ZFSCACHE" */ #define L2ARC_LOG_BLK_MAGIC 0x4c4f47424c4b4844LLU /* ASCII: "LOGBLKHD" */ /* * L2ARC Internals */ typedef struct l2arc_dev { vdev_t *l2ad_vdev; /* vdev */ spa_t *l2ad_spa; /* spa */ uint64_t l2ad_hand; /* next write location */ uint64_t l2ad_start; /* first addr on device */ uint64_t l2ad_end; /* last addr on device */ boolean_t l2ad_first; /* first sweep through */ boolean_t l2ad_writing; /* currently writing */ kmutex_t l2ad_mtx; /* lock for buffer list */ list_t l2ad_buflist; /* buffer list */ list_node_t l2ad_node; /* device list node */ zfs_refcount_t l2ad_alloc; /* allocated bytes */ /* * Persistence-related stuff */ l2arc_dev_hdr_phys_t *l2ad_dev_hdr; /* persistent device header */ uint64_t l2ad_dev_hdr_asize; /* aligned hdr size */ l2arc_log_blk_phys_t l2ad_log_blk; /* currently open log block */ int l2ad_log_ent_idx; /* index into cur log blk */ /* Number of bytes in current log block's payload */ uint64_t l2ad_log_blk_payload_asize; /* * Offset (in bytes) of the first buffer in current log block's * payload. */ uint64_t l2ad_log_blk_payload_start; /* Flag indicating whether a rebuild is scheduled or is going on */ boolean_t l2ad_rebuild; boolean_t l2ad_rebuild_cancel; boolean_t l2ad_rebuild_began; uint64_t l2ad_log_entries; /* entries per log blk */ uint64_t l2ad_evict; /* evicted offset in bytes */ /* List of pointers to log blocks present in the L2ARC device */ list_t l2ad_lbptr_list; /* * Aligned size of all log blocks as accounted by vdev_space_update(). */ zfs_refcount_t l2ad_lb_asize; /* * Number of log blocks present on the device. */ zfs_refcount_t l2ad_lb_count; boolean_t l2ad_trim_all; /* TRIM whole device */ } l2arc_dev_t; /* * Encrypted blocks will need to be stored encrypted on the L2ARC * disk as they appear in the main pool. In order for this to work we * need to pass around the encryption parameters so they can be used * to write data to the L2ARC. This struct is only defined in the * arc_buf_hdr_t if the L1 header is defined and has the ARC_FLAG_ENCRYPTED * flag set. */ typedef struct arc_buf_hdr_crypt { abd_t *b_rabd; /* raw encrypted data */ dmu_object_type_t b_ot; /* object type */ uint32_t b_ebufcnt; /* count of encrypted buffers */ /* dsobj for looking up encryption key for l2arc encryption */ uint64_t b_dsobj; /* encryption parameters */ uint8_t b_salt[ZIO_DATA_SALT_LEN]; uint8_t b_iv[ZIO_DATA_IV_LEN]; /* * Technically this could be removed since we will always be able to * get the mac from the bp when we need it. However, it is inconvenient * for callers of arc code to have to pass a bp in all the time. This * also allows us to assert that L2ARC data is properly encrypted to * match the data in the main storage pool. */ uint8_t b_mac[ZIO_DATA_MAC_LEN]; } arc_buf_hdr_crypt_t; typedef struct l2arc_buf_hdr { /* protected by arc_buf_hdr mutex */ l2arc_dev_t *b_dev; /* L2ARC device */ uint64_t b_daddr; /* disk address, offset byte */ uint32_t b_hits; list_node_t b_l2node; } l2arc_buf_hdr_t; typedef struct l2arc_write_callback { l2arc_dev_t *l2wcb_dev; /* device info */ arc_buf_hdr_t *l2wcb_head; /* head of write buflist */ /* in-flight list of log blocks */ list_t l2wcb_abd_list; } l2arc_write_callback_t; struct arc_buf_hdr { /* protected by hash lock */ dva_t b_dva; uint64_t b_birth; arc_buf_contents_t b_type; arc_buf_hdr_t *b_hash_next; arc_flags_t b_flags; /* * This field stores the size of the data buffer after * compression, and is set in the arc's zio completion handlers. * It is in units of SPA_MINBLOCKSIZE (e.g. 1 == 512 bytes). * * While the block pointers can store up to 32MB in their psize * field, we can only store up to 32MB minus 512B. This is due * to the bp using a bias of 1, whereas we use a bias of 0 (i.e. * a field of zeros represents 512B in the bp). We can't use a * bias of 1 since we need to reserve a psize of zero, here, to * represent holes and embedded blocks. * * This isn't a problem in practice, since the maximum size of a * buffer is limited to 16MB, so we never need to store 32MB in * this field. Even in the upstream illumos code base, the * maximum size of a buffer is limited to 16MB. */ uint16_t b_psize; /* * This field stores the size of the data buffer before * compression, and cannot change once set. It is in units * of SPA_MINBLOCKSIZE (e.g. 2 == 1024 bytes) */ uint16_t b_lsize; /* immutable */ uint64_t b_spa; /* immutable */ /* L2ARC fields. Undefined when not in L2ARC. */ l2arc_buf_hdr_t b_l2hdr; /* L1ARC fields. Undefined when in l2arc_only state */ l1arc_buf_hdr_t b_l1hdr; /* * Encryption parameters. Defined only when ARC_FLAG_ENCRYPTED * is set and the L1 header exists. */ arc_buf_hdr_crypt_t b_crypt_hdr; }; typedef struct arc_stats { kstat_named_t arcstat_hits; kstat_named_t arcstat_misses; kstat_named_t arcstat_demand_data_hits; kstat_named_t arcstat_demand_data_misses; kstat_named_t arcstat_demand_metadata_hits; kstat_named_t arcstat_demand_metadata_misses; kstat_named_t arcstat_prefetch_data_hits; kstat_named_t arcstat_prefetch_data_misses; kstat_named_t arcstat_prefetch_metadata_hits; kstat_named_t arcstat_prefetch_metadata_misses; kstat_named_t arcstat_mru_hits; kstat_named_t arcstat_mru_ghost_hits; kstat_named_t arcstat_mfu_hits; kstat_named_t arcstat_mfu_ghost_hits; kstat_named_t arcstat_deleted; /* * Number of buffers that could not be evicted because the hash lock * was held by another thread. The lock may not necessarily be held * by something using the same buffer, since hash locks are shared * by multiple buffers. */ kstat_named_t arcstat_mutex_miss; /* * Number of buffers skipped when updating the access state due to the * header having already been released after acquiring the hash lock. */ kstat_named_t arcstat_access_skip; /* * Number of buffers skipped because they have I/O in progress, are * indirect prefetch buffers that have not lived long enough, or are * not from the spa we're trying to evict from. */ kstat_named_t arcstat_evict_skip; /* * Number of times arc_evict_state() was unable to evict enough * buffers to reach its target amount. */ kstat_named_t arcstat_evict_not_enough; kstat_named_t arcstat_evict_l2_cached; kstat_named_t arcstat_evict_l2_eligible; kstat_named_t arcstat_evict_l2_ineligible; kstat_named_t arcstat_evict_l2_skip; kstat_named_t arcstat_hash_elements; kstat_named_t arcstat_hash_elements_max; kstat_named_t arcstat_hash_collisions; kstat_named_t arcstat_hash_chains; kstat_named_t arcstat_hash_chain_max; kstat_named_t arcstat_p; kstat_named_t arcstat_c; kstat_named_t arcstat_c_min; kstat_named_t arcstat_c_max; /* Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_size; /* * Number of compressed bytes stored in the arc_buf_hdr_t's b_pabd. * Note that the compressed bytes may match the uncompressed bytes * if the block is either not compressed or compressed arc is disabled. */ kstat_named_t arcstat_compressed_size; /* * Uncompressed size of the data stored in b_pabd. If compressed * arc is disabled then this value will be identical to the stat * above. */ kstat_named_t arcstat_uncompressed_size; /* * Number of bytes stored in all the arc_buf_t's. This is classified * as "overhead" since this data is typically short-lived and will * be evicted from the arc when it becomes unreferenced unless the * zfs_keep_uncompressed_metadata or zfs_keep_uncompressed_level * values have been set (see comment in dbuf.c for more information). */ kstat_named_t arcstat_overhead_size; /* * Number of bytes consumed by internal ARC structures necessary * for tracking purposes; these structures are not actually * backed by ARC buffers. This includes arc_buf_hdr_t structures * (allocated via arc_buf_hdr_t_full and arc_buf_hdr_t_l2only * caches), and arc_buf_t structures (allocated via arc_buf_t * cache). * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_hdr_size; /* * Number of bytes consumed by ARC buffers of type equal to * ARC_BUFC_DATA. This is generally consumed by buffers backing * on disk user data (e.g. plain file contents). * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_data_size; /* * Number of bytes consumed by ARC buffers of type equal to * ARC_BUFC_METADATA. This is generally consumed by buffers * backing on disk data that is used for internal ZFS * structures (e.g. ZAP, dnode, indirect blocks, etc). * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_metadata_size; /* * Number of bytes consumed by dmu_buf_impl_t objects. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_dbuf_size; /* * Number of bytes consumed by dnode_t objects. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_dnode_size; /* * Number of bytes consumed by bonus buffers. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_bonus_size; /* * Total number of bytes consumed by ARC buffers residing in the * arc_anon state. This includes *all* buffers in the arc_anon * state; e.g. data, metadata, evictable, and unevictable buffers * are all included in this value. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_anon_size; /* * Number of bytes consumed by ARC buffers that meet the * following criteria: backing buffers of type ARC_BUFC_DATA, * residing in the arc_anon state, and are eligible for eviction * (e.g. have no outstanding holds on the buffer). * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_anon_evictable_data; /* * Number of bytes consumed by ARC buffers that meet the * following criteria: backing buffers of type ARC_BUFC_METADATA, * residing in the arc_anon state, and are eligible for eviction * (e.g. have no outstanding holds on the buffer). * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_anon_evictable_metadata; /* * Total number of bytes consumed by ARC buffers residing in the * arc_mru state. This includes *all* buffers in the arc_mru * state; e.g. data, metadata, evictable, and unevictable buffers * are all included in this value. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mru_size; /* * Number of bytes consumed by ARC buffers that meet the * following criteria: backing buffers of type ARC_BUFC_DATA, * residing in the arc_mru state, and are eligible for eviction * (e.g. have no outstanding holds on the buffer). * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mru_evictable_data; /* * Number of bytes consumed by ARC buffers that meet the * following criteria: backing buffers of type ARC_BUFC_METADATA, * residing in the arc_mru state, and are eligible for eviction * (e.g. have no outstanding holds on the buffer). * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mru_evictable_metadata; /* * Total number of bytes that *would have been* consumed by ARC * buffers in the arc_mru_ghost state. The key thing to note * here, is the fact that this size doesn't actually indicate * RAM consumption. The ghost lists only consist of headers and * don't actually have ARC buffers linked off of these headers. * Thus, *if* the headers had associated ARC buffers, these * buffers *would have* consumed this number of bytes. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mru_ghost_size; /* * Number of bytes that *would have been* consumed by ARC * buffers that are eligible for eviction, of type * ARC_BUFC_DATA, and linked off the arc_mru_ghost state. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mru_ghost_evictable_data; /* * Number of bytes that *would have been* consumed by ARC * buffers that are eligible for eviction, of type * ARC_BUFC_METADATA, and linked off the arc_mru_ghost state. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mru_ghost_evictable_metadata; /* * Total number of bytes consumed by ARC buffers residing in the * arc_mfu state. This includes *all* buffers in the arc_mfu * state; e.g. data, metadata, evictable, and unevictable buffers * are all included in this value. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mfu_size; /* * Number of bytes consumed by ARC buffers that are eligible for * eviction, of type ARC_BUFC_DATA, and reside in the arc_mfu * state. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mfu_evictable_data; /* * Number of bytes consumed by ARC buffers that are eligible for * eviction, of type ARC_BUFC_METADATA, and reside in the * arc_mfu state. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mfu_evictable_metadata; /* * Total number of bytes that *would have been* consumed by ARC * buffers in the arc_mfu_ghost state. See the comment above * arcstat_mru_ghost_size for more details. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mfu_ghost_size; /* * Number of bytes that *would have been* consumed by ARC * buffers that are eligible for eviction, of type * ARC_BUFC_DATA, and linked off the arc_mfu_ghost state. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mfu_ghost_evictable_data; /* * Number of bytes that *would have been* consumed by ARC * buffers that are eligible for eviction, of type * ARC_BUFC_METADATA, and linked off the arc_mru_ghost state. * Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_mfu_ghost_evictable_metadata; kstat_named_t arcstat_l2_hits; kstat_named_t arcstat_l2_misses; kstat_named_t arcstat_l2_feeds; kstat_named_t arcstat_l2_rw_clash; kstat_named_t arcstat_l2_read_bytes; kstat_named_t arcstat_l2_write_bytes; kstat_named_t arcstat_l2_writes_sent; kstat_named_t arcstat_l2_writes_done; kstat_named_t arcstat_l2_writes_error; kstat_named_t arcstat_l2_writes_lock_retry; kstat_named_t arcstat_l2_evict_lock_retry; kstat_named_t arcstat_l2_evict_reading; kstat_named_t arcstat_l2_evict_l1cached; kstat_named_t arcstat_l2_free_on_write; kstat_named_t arcstat_l2_abort_lowmem; kstat_named_t arcstat_l2_cksum_bad; kstat_named_t arcstat_l2_io_error; kstat_named_t arcstat_l2_lsize; kstat_named_t arcstat_l2_psize; /* Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_l2_hdr_size; /* * Number of L2ARC log blocks written. These are used for restoring the * L2ARC. Updated during writing of L2ARC log blocks. */ kstat_named_t arcstat_l2_log_blk_writes; /* * Moving average of the aligned size of the L2ARC log blocks, in * bytes. Updated during L2ARC rebuild and during writing of L2ARC * log blocks. */ kstat_named_t arcstat_l2_log_blk_avg_asize; /* Aligned size of L2ARC log blocks on L2ARC devices. */ kstat_named_t arcstat_l2_log_blk_asize; /* Number of L2ARC log blocks present on L2ARC devices. */ kstat_named_t arcstat_l2_log_blk_count; /* * Moving average of the aligned size of L2ARC restored data, in bytes, * to the aligned size of their metadata in L2ARC, in bytes. * Updated during L2ARC rebuild and during writing of L2ARC log blocks. */ kstat_named_t arcstat_l2_data_to_meta_ratio; /* * Number of times the L2ARC rebuild was successful for an L2ARC device. */ kstat_named_t arcstat_l2_rebuild_success; /* * Number of times the L2ARC rebuild failed because the device header * was in an unsupported format or corrupted. */ kstat_named_t arcstat_l2_rebuild_abort_unsupported; /* * Number of times the L2ARC rebuild failed because of IO errors * while reading a log block. */ kstat_named_t arcstat_l2_rebuild_abort_io_errors; /* * Number of times the L2ARC rebuild failed because of IO errors when * reading the device header. */ kstat_named_t arcstat_l2_rebuild_abort_dh_errors; /* * Number of L2ARC log blocks which failed to be restored due to * checksum errors. */ kstat_named_t arcstat_l2_rebuild_abort_cksum_lb_errors; /* * Number of times the L2ARC rebuild was aborted due to low system * memory. */ kstat_named_t arcstat_l2_rebuild_abort_lowmem; /* Logical size of L2ARC restored data, in bytes. */ kstat_named_t arcstat_l2_rebuild_size; /* Aligned size of L2ARC restored data, in bytes. */ kstat_named_t arcstat_l2_rebuild_asize; /* * Number of L2ARC log entries (buffers) that were successfully * restored in ARC. */ kstat_named_t arcstat_l2_rebuild_bufs; /* * Number of L2ARC log entries (buffers) already cached in ARC. These * were not restored again. */ kstat_named_t arcstat_l2_rebuild_bufs_precached; /* * Number of L2ARC log blocks that were restored successfully. Each * log block may hold up to L2ARC_LOG_BLK_MAX_ENTRIES buffers. */ kstat_named_t arcstat_l2_rebuild_log_blks; kstat_named_t arcstat_memory_throttle_count; kstat_named_t arcstat_memory_direct_count; kstat_named_t arcstat_memory_indirect_count; kstat_named_t arcstat_memory_all_bytes; kstat_named_t arcstat_memory_free_bytes; kstat_named_t arcstat_memory_available_bytes; kstat_named_t arcstat_no_grow; kstat_named_t arcstat_tempreserve; kstat_named_t arcstat_loaned_bytes; kstat_named_t arcstat_prune; /* Not updated directly; only synced in arc_kstat_update. */ kstat_named_t arcstat_meta_used; kstat_named_t arcstat_meta_limit; kstat_named_t arcstat_dnode_limit; kstat_named_t arcstat_meta_max; kstat_named_t arcstat_meta_min; kstat_named_t arcstat_async_upgrade_sync; kstat_named_t arcstat_demand_hit_predictive_prefetch; kstat_named_t arcstat_demand_hit_prescient_prefetch; kstat_named_t arcstat_need_free; kstat_named_t arcstat_sys_free; kstat_named_t arcstat_raw_size; kstat_named_t arcstat_cached_only_in_progress; } arc_stats_t; typedef struct arc_evict_waiter { list_node_t aew_node; kcondvar_t aew_cv; uint64_t aew_count; } arc_evict_waiter_t; #define ARCSTAT(stat) (arc_stats.stat.value.ui64) #define ARCSTAT_INCR(stat, val) \ atomic_add_64(&arc_stats.stat.value.ui64, (val)) #define ARCSTAT_BUMP(stat) ARCSTAT_INCR(stat, 1) #define ARCSTAT_BUMPDOWN(stat) ARCSTAT_INCR(stat, -1) #define arc_no_grow ARCSTAT(arcstat_no_grow) /* do not grow cache size */ #define arc_p ARCSTAT(arcstat_p) /* target size of MRU */ #define arc_c ARCSTAT(arcstat_c) /* target size of cache */ #define arc_c_min ARCSTAT(arcstat_c_min) /* min target cache size */ #define arc_c_max ARCSTAT(arcstat_c_max) /* max target cache size */ #define arc_sys_free ARCSTAT(arcstat_sys_free) /* target system free bytes */ extern taskq_t *arc_prune_taskq; extern arc_stats_t arc_stats; extern hrtime_t arc_growtime; extern boolean_t arc_warm; extern int arc_grow_retry; extern int arc_no_grow_shift; extern int arc_shrink_shift; extern kmutex_t arc_prune_mtx; extern list_t arc_prune_list; extern aggsum_t arc_size; extern arc_state_t *arc_mfu; extern arc_state_t *arc_mru; extern uint_t zfs_arc_pc_percent; extern int arc_lotsfree_percent; extern unsigned long zfs_arc_min; extern unsigned long zfs_arc_max; extern void arc_reduce_target_size(int64_t to_free); extern boolean_t arc_reclaim_needed(void); extern void arc_kmem_reap_soon(void); extern boolean_t arc_is_overflowing(void); extern void arc_wait_for_eviction(uint64_t); extern void arc_lowmem_init(void); extern void arc_lowmem_fini(void); extern void arc_prune_async(int64_t); extern int arc_memory_throttle(spa_t *spa, uint64_t reserve, uint64_t txg); extern uint64_t arc_free_memory(void); extern int64_t arc_available_memory(void); extern void arc_tuning_update(boolean_t); extern int param_set_arc_long(ZFS_MODULE_PARAM_ARGS); extern int param_set_arc_int(ZFS_MODULE_PARAM_ARGS); /* used in zdb.c */ boolean_t l2arc_log_blkptr_valid(l2arc_dev_t *dev, const l2arc_log_blkptr_t *lbp); /* used in vdev_trim.c */ void l2arc_dev_hdr_update(l2arc_dev_t *dev); l2arc_dev_t *l2arc_vdev_get(vdev_t *vd); #ifdef __cplusplus } #endif #endif /* _SYS_ARC_IMPL_H */