cc3149b1ea
atomic write request, it can fill the buffer cache with the entirety of that write in order to handle retries. However, it never drops the vnode lock, or else it wouldn't be atomic, so it ends up waiting indefinitely for more buf memory that cannot be gotten as it has it all, and it waits in an uncancellable state. To fix this, hibufspace is exported and scaled to a reasonable fraction. This is used as the limit of how much of an atomic write request by the NFS client will be handled asynchronously. If the request is larger than this, it will be turned into a synchronous request which won't deadlock the system. It's possible this value is far off from what is required by some, so it shall be tunable as soon as mount_nfs(8) learns of the new field. The slowdown between an asynchronous and a synchronous write on NFS appears to be on the order of 2x-4x. General nod by: gad MFC after: 2 weeks More testing: wes PR: kern/79208 |
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| .. | ||
| bootp_subr.c | ||
| krpc_subr.c | ||
| krpc.h | ||
| nfs_bio.c | ||
| nfs_diskless.c | ||
| nfs_lock.c | ||
| nfs_lock.h | ||
| nfs_nfsiod.c | ||
| nfs_node.c | ||
| nfs_socket.c | ||
| nfs_subs.c | ||
| nfs_vfsops.c | ||
| nfs_vnops.c | ||
| nfs.h | ||
| nfsargs.h | ||
| nfsdiskless.h | ||
| nfsm_subs.h | ||
| nfsmount.h | ||
| nfsnode.h | ||
| nfsstats.h | ||
| nlminfo.h | ||