Hey Bruce! While testing with sec=krb5 and sec=krb5i, I noticed a lot of spurious connection loss, especially when I wanted to run a CPU-intensive workload on my NFS server at the same time I was testing. I added a pr_err() in gss_check_seq_num, and ran a fio job on a vers=3,sec=sys,proto=tcp mount (server is exporting a tmpfs). On the server, I rebuilt a kernel source tree cscope database at the same time. May 29 17:53:13 klimt kernel: gss_check_seq_num: seq_num = 250098, sd_max = 250291, GSS_SEQ_WIN = 128 May 29 17:53:33 klimt kernel: gss_check_seq_num: seq_num = 937816, sd_max = 938171, GSS_SEQ_WIN = 128 May 29 17:53:33 klimt kernel: gss_check_seq_num: seq_num = 938544, sd_max = 938727, GSS_SEQ_WIN = 128 May 29 17:53:33 klimt kernel: gss_check_seq_num: seq_num = 938543, sd_max = 938727, GSS_SEQ_WIN = 128 May 29 17:53:34 klimt kernel: gss_check_seq_num: seq_num = 939344, sd_max = 939549, GSS_SEQ_WIN = 128 May 29 17:53:35 klimt kernel: gss_check_seq_num: seq_num = 965007, sd_max = 965176, GSS_SEQ_WIN = 128 May 29 17:54:01 klimt kernel: gss_check_seq_num: seq_num = 1799710, sd_max = 1799982, GSS_SEQ_WIN = 128 May 29 17:54:02 klimt kernel: gss_check_seq_num: seq_num = 1831165, sd_max = 1831353, GSS_SEQ_WIN = 128 May 29 17:54:04 klimt kernel: gss_check_seq_num: seq_num = 1883583, sd_max = 1883761, GSS_SEQ_WIN = 128 May 29 17:54:07 klimt kernel: gss_check_seq_num: seq_num = 1959316, sd_max = 1959447, GSS_SEQ_WIN = 128 RFC 2203 suggests there's no risk to using a large window. My first thought was to make the sequence window larger (say 2048) but I've seen stragglers outside even that large a window. Any thoughts about why there are these sequence number outliers? -- Chuck Lever -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
