• Trond Myklebust's avatar
    nfsd: Do not refuse to serve out of cache · 7e5d0e0d
    Trond Myklebust authored
    Currently the knfsd replay cache appears to try to refuse replying to
    retries that come within 200ms of the cache entry being created. That
    makes limited sense in today's world of high speed TCP.
    
    After a TCP disconnection, a client can very easily reconnect and retry
    an rpc in less than 200ms.  If this logic drops that retry, however, the
    client may be quite slow to retry again.  This logic is original to the
    first reply cache implementation in 2.1, and may have made more sense
    for UDP clients that retried much more frequently.
    
    After this patch we will still drop on finding the original request
    still in progress.  We may want to fix that as well at some point,
    though it's less likely.
    
    Note that svc_check_conn_limits is often the cause of those
    disconnections.  We may want to fix that some day.
    Signed-off-by: default avatarTrond Myklebust <trond.myklebust@primarydata.com>
    Acked-by: default avatarJeff Layton <jlayton@kernel.org>
    Signed-off-by: default avatarJ. Bruce Fields <bfields@redhat.com>
    7e5d0e0d
nfscache.c 15.4 KB