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@d-helios d-helios/
Last active Nov 14, 2017

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General Caches

  • kmem_cache: internal cache of cache description objects
  • size-N: Generic cache of size N
  • size-N(DMA): Generic cache of size N for direct memory access use


  • flow_cache: Generic flow cache
  • RPC
    • rpc_buffers: RPC requests, data buffers
    • rpc_tasks: RPC requests, task structures
    • rpc_inode_cache: RPC requests, inodes
  • TCP/IP
    • ip_fib_alias: IP Datagram forwarding
    • ip_fib_hash: IP Datagram forwarding
    • ip_mrt_cache: IP multicast routing
    • tcp_tw_bucket: Time Wait
    • tcp_bind_bucket: Socket-interface bindings
    • tcp_open_request: Open TCP requests
    • inet_peer_cache:Storage for permanent information about peers
    • arp_cache: Address resolution protocol caches
  • Sockets
    • unix_sock: BSD Unix domain sockets
    • raw_sock: Raw socket
    • udp_sock: Unix Datagram Protocol sockets
    • tcp_sock: Transmission control protocol sockets
    • sock_inode_cache: Socket inodes
    • skbuff_head_cache: Socket buffers
    • sock: Sockets


  • Device Mapper
    • dm_tio: Target I/Os
    • dm_io: Basic DM I/Os
    • dm-bvec-N: Device mapper block I/O vector of size N bytes.
    • dm-bio: Basic DM block I/O structures
  • SCSI
    • scsi_cmd_cache: SCSI command pool
    • sgpool-N: SCSI queuing pool of size N bytes


  • General
    • buffer_head: Filesystem buffers
    • bdev_cache: Filesystem block device cache
    • mnt_cache: Virtual filesystem mount caching
    • audit_watch_cache: Filesystem auditing
    • inode_cache: Index node caching
    • file_lock_cache: Generic filesystem file locking
    • dquot: Disk quota
    • dnotify_cache: Directory notifications
    • Directory entry caching
      • dentry_cache: Directory entry caches
      • filp: File pointer cache
      • names_cache: Pathname cache
    • EXT2/3
      • ext3_inode_cache: EXT3 I-Node cache
      • ext3_xattr: EXT3 extended attributes
      • ext2_inode_cache: EXT2 I-node cache
      • ext2_xattr: EXT2 extended attributes
    • General Filesystem Journaling
      • journal_handle:Journal identifier/handles cache
      • journal_head: Journal list heads
      • revoke_table: Revoked record tables
      • revoke_record: Revoked records

Asynchronous I/O

  • kioctx: Asynchronous I/O context structures
  • kiocb: Asynchronous I/O control blocks

I/O Scheduling

  • crq_pool: Complete fairness queuing (CFQ) request pool
  • cfq_pool: Cache for CFQ queues
  • deadline_drq: Prerequest data cache for deadline scheduler
  • as_arq: Data requests cache for anticipatory scheduler
  • Block Device I/O
  • blkdev_ioc: Block device I/O context
  • blkdev_queue: Block device I/O request queue
  • blkdev_requests: Block device request entities
  • biovec-N: Block I/O vector of size N bytes
  • bio: Cache of main units of I/O for the block layer and lower layers


  • mm_struct: Per process memory management structure data allocated by each new process
  • vm_area_struct: Per process virtual memory area data allocated by each new process
  • fs_cache: Per process filesystem related data allocated by each new process
  • files_cache: Per process file related data allocated by each new process
  • signal_cache: Per process signal cache allocated by each new process
  • sighand_cache: Per process signal handlers cache allocated by each new process
  • task_struct: Task information for every new process forked
  • uid_cache: Per user structure to keep track of user processes

Memory Management

  • anon_vma: Anonymous virtual memory addresses for physical to virtual reverse mappings
  • hugetlbfs_inode_cache: hugetlbpage-backed filesystem cache
  • shmem_inode_cache: shmfs - Resizable virtual memory filesystem
  • pmd: Page middle directory
  • pgd: Page global directory


  • radix_tree_node: Generic radix tree implementation
  • idr_layer_cache: Small id to pointer translation cache
  • avc_node: SELinux kernel access vector cache
  • key_jar: Key caching for basic authentication token and access key management
  • proc_inode_cache: Proc filesystem implementation
  • sigqueue: The kernel signal handing queue
  • posix_timers_cache: Posix system timer handling
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