remote rtape problem

[richard welty <steinmetz!welty@uunet.uu.net>]

We've encountered a sporadic but extrememly annoying problem with remote
rtape while trying to backup a lmfs over the network.  Maybe someone
can shed some light on the problem.

Typically, a couple of tapes into a backup, the backup will stall, with
each machine waiting on the other (I've included complete backtraces
for both machines at the end of this message.)  Once this happens,
it is apparently impossible to get the system unwedged without
rebooting (at least, I've not figured out how.)

The namespace shows the entry for the rtape server is TAPE CHAOS RTAPE,
which seems correct (and which works for a couple of tapes, at least.)

I'm quite baffled by all of this.

---------------
Backtrace from fileserver:
---------------
Tape ackbarf3 mounted on drive CART.

Break: 

Rebinding the following specials; use Show Standard Value Warnings for details:
  *PRINT-LENGTH* and ZL:PACKAGE

PROCESS-WAIT:
   Arg 0 (SI:WHOSTATE): "Chaos In"
   Arg 1 (FUNCTION): #<LEXICAL-CLOSURE (:INTERNAL # 0) 231101001>
   Rest arg (SI:ARGUMENTS): NIL
s-A, <resume>:   Proceed without any special action
s-B, <abort>:    Return to FS Maintenance Lisp Listener in Fsmaint Interaction Pane 1
s-C:           FS Maintenance Top Level
s-D:           Restart process Fsmaint Frame 1
-> :Show Backtrace
PROCESS-WAIT <- (FLAVOR:METHOD :INPUT-EXCEPTION-WAIT SI:INPUT-STREAM-EXCEPTION-MIXIN) <- CHAOS:GET-NEXT-PKT
 <- (FLAVOR:METHOD :GET-NEXT-INPUT-PKT CHAOS:BASIC-INPUT-STREAM) <- (FLAVOR:METHOD :NEXT-INPUT-BUFFER CHAOS:BINARY8-INPUT-STREAM-MIXIN)
 <- (FLAVOR:METHOD :SETUP-NEXT-INPUT-BUFFER SI:BASIC-BUFFERED-INPUT-STREAM) <- (FLAVOR:METHOD :TYI SI:BASIC-BUFFERED-INPUT-STREAM)
 <- (FLAVOR:METHOD :SET-RS-PARAMS SI:RECORD-STREAM-INPUT-MIXIN)
 <- (DEFUN-IN-FLAVOR SI:RECORD-STREAM-INPUT-PARAMABLE-STATE SI:RECORD-STREAM-INPUT-MIXIN)
 <- (FLAVOR:METHOD :OPCODE SI:RECORD-STREAM-INPUT-MIXIN)
 <- (DEFUN-IN-FLAVOR TAPE:REMOTE-TAPE-INPUT-MIXIN-GET-MORE-STATE TAPE:REMOTE-TAPE-INPUT-MIXIN)
 <- (DEFUN-IN-FLAVOR TAPE:REMOTE-TAPE-INPUT-MIXIN-NONZEROIFY-STATE TAPE:REMOTE-TAPE-INPUT-MIXIN)
 <- (FLAVOR:METHOD :NEXT-INPUT-BUFFER TAPE:REMOTE-TAPE-INPUT-MIXIN)
 <- (FLAVOR:METHOD :SETUP-NEXT-INPUT-BUFFER SI:BASIC-BUFFERED-INPUT-STREAM) <- (FLAVOR:METHOD :TYI SI:BASIC-BUFFERED-INPUT-STREAM)
 <- (FLAVOR:METHOD :TYI SI:8BIT-BINARY-STREAM-ASSOCIATED-THIN-CHARACTER-INPUT-STREAM)
 <- (FLAVOR:METHOD :STRING-IN SI:INPUT-STREAM :DEFAULT) <- LMFS:IDENTIFY-MOUNTED-TAPE
 <- LMFS:BACKUP-MAKE-STATEMENTS-ABOUT-THE-MOUNTED-TAPE <- LMFS:BACKUP-DEAL-WITH-BOT <- LMFS:BACKUP-DUMP-I <- LMFS:BACKUP-DUMPER
 <- (FLAVOR:METHOD :COMMAND-EXECUTE LMFS:FSMAINT-FRAME :COMPLETE-DUMP) <- (FLAVOR:COMBINED :COMMAND-EXECUTE LMFS:FSMAINT-FRAME)
 <- (FLAVOR:METHOD :INTERPRET-INPUT LMFS:FSMAINT-FRAME) <- LMFS:FSMAINT-READ-FCN <- TV:WITH-NOTIFICATION-MODE-INTERNAL
 <- SI:LISP-COMMAND-LOOP-INTERNAL <- SI:LISP-COMMAND-LOOP <- (FLAVOR:METHOD :FSMAINT-TOP-LEVEL LMFS:FSMAINT-FRAME)
 <- LMFS:FSMAINT-TOP-LEVEL <- SI:PROCESS-TOP-LEVEL

------------
backtrace from rtape server:
------------

Break: 

Rebinding the following specials; use Show Standard Value Warnings for details:
  CL:*READ-BASE* and CL:*PRINT-BASE*

PROCESS-WAIT:
   Arg 0 (SI:WHOSTATE): "Cart tape"
   Arg 1 (FUNCTION): #<DTP-COMPILED-FUNCTION (:INTERNAL (FLAVOR:METHOD :AWAIT-WINDOW TAPE:CART-TAPE-STREAM-MIXIN) 0) 151654456>
   Rest arg (SI:ARGUMENTS): (63)
s-A, <resume>:   Proceed without any special action
s-B, <abort>:    Allow process to continue
s-C:           Exit process RTAPE server
s-D:           Restart process RTAPE server
-> :Show Backtrace
PROCESS-WAIT <- (FLAVOR:METHOD :AWAIT-WINDOW TAPE:CART-TAPE-STREAM-MIXIN)
 <- (FLAVOR:METHOD :NEXT-INPUT-BUFFER TAPE:CART-TAPE-INPUT-MIXIN)
 <- (FLAVOR:COMBINED :NEXT-INPUT-BUFFER TAPE:CART-BIDIRECTIONAL-STREAM)
 <- (FLAVOR:METHOD :SETUP-NEXT-INPUT-BUFFER SI:BASIC-BUFFERED-INPUT-STREAM)
 <- (FLAVOR:METHOD :READ-INPUT-BUFFER SI:BUFFERED-INPUT-STREAM)
 <- (DEFUN-IN-FLAVOR TAPE:RTAPE-SERVER-REALLY-READ TAPE:RTAPE-SERVER-INSTANCE)
 <- (DEFUN-IN-FLAVOR TAPE:RTAPE-SERVER-READ TAPE:RTAPE-SERVER-INSTANCE) <- (FLAVOR:METHOD :SERVE TAPE:RTAPE-SERVER-INSTANCE)
 <- (FLAVOR:METHOD :SERVER-TOP-LEVEL TAPE:RTAPE-SERVER-INSTANCE) <- NETI:FUNCALL-SERVER-FUNCTION
 <- NETI:BYTE-STREAM-INVOKE-SERVICE-FUNCTION <- NETI:INVOKE-SERVER-INTERNAL <- (:INTERNAL NETI:INVOKE-SERVER 0)
 <- (:INTERNAL NET:PROCESS-RUN-FUNCTION-IN-SECURE-ENVIRONMENT 0) <- SI:PROCESS-RUN-FUNCTION-INTERNAL <- SI:PROCESS-TOP-LEVEL
----------------
Thanks,
    Richard
--
Richard Welty  518-387-6346  GE R&D, K1-5C39, Niskayuna, New York
   welty@ge-crd.ARPA  {uunet,philabs,rochester}!steinmetz!welty
``once again, baked goods lead th' way to enlightenment'' -- zippy