[Swift-devel] Re: Swift hanging in complex iterate script

[Mihael Hategan]

Beautiful. Deadlock right there. I'll see what I can do.

On Thu, 2010-09-16 at 13:07 -0600, Michael Wilde wrote:
> OK, thats in ~wilde/swiftrhang/jstack.out
> 
> The jvm is still running: pid 22435 on bridled. Let me know if you need any other traces from it.
> 
> It hung around 12:05
> 
> - Mike
> 
> 
> bri$ mp
> UID        PID  PPID  PGID   SID  C STIME TTY          TIME CMD
> wilde    19025 19023 19023 19023  0 11:49 ?        00:00:00 sshd: wilde at pts/29
> wilde    19026 19025 19026 19026  0 11:49 pts/29   00:00:00   -bash
> wilde    19203 19026 19203 19026  0 11:49 pts/29   00:00:00     /usr/bin/screen -x
> wilde    15373 15371 15371 15371  0 06:58 ?        00:00:00 sshd: wilde at pts/14
> wilde    15374 15373 15374 15374  0 06:58 pts/14   00:00:00   -bash
> wilde    18291 15374 18291 15374  0 11:47 pts/14   00:00:00     /home/wilde/R/R-2.11.0/bin/exec/R
> wilde    11315 15374 11315 15374  0 13:59 pts/14   00:00:00     /usr/bin/screen -x
> wilde    15183 15181 15181 15181  0 06:58 ?        00:00:00 sshd: wilde at pts/11
> wilde    15184 15183 15184 15184  0 06:58 pts/11   00:00:00   -bash
> wilde    15835 15184 15835 15184  0 06:59 pts/11   00:00:00     /usr/bin/screen
> wilde    15836 15835 15836 15836  0 06:59 ?        00:00:00       /usr/bin/SCREEN
> wilde    15837 15836 15837 15837  0 06:59 pts/15   00:00:00         bash
> wilde    15839 15836 15839 15839  0 06:59 pts/16   00:00:00         bash
> wilde    15841 15836 15841 15841  0 06:59 pts/19   00:00:00         bash
> wilde    15843 15836 15843 15843  0 06:59 pts/20   00:00:00         bash
> wilde    15845 15836 15845 15845  0 06:59 pts/21   00:00:00         bash
> wilde    15847 15836 15847 15847  0 06:59 pts/22   00:00:00         bash
> wilde    14845 15847 14845 15847  0 10:05 pts/22   00:00:00           emacs Swift/exec/start-swift-workers
> wilde    22364 15847 22364 15847  0 11:59 pts/22   00:00:00           /bin/bash Swift/exec/RunRServer.sh
> wilde    22378 22364 22364 15847  0 11:59 pts/22   00:00:00             /bin/sh /home/wilde/swift/rev/trunk/bin/swift -config swift.pr
> wilde    22435 22378 22364 15847  0 11:59 pts/22   00:00:29               java -Xmx256M -Djava.endorsed.dirs=/home/wilde/swift/rev/tru
> wilde    12506 15847 12506 15847  0 14:03 pts/22   00:00:00           ps -fjH -u wilde
> wilde    22930     1 22364 15847  0 11:59 pts/22   00:00:05 /home/wilde/R/R-2.11.0/bin/exec/R --slave --no-restore --file=./SwiftRServ
> wilde    22926     1 22364 15847  0 11:59 pts/22   00:00:04 /home/wilde/R/R-2.11.0/bin/exec/R --slave --no-restore --file=./SwiftRServ
> wilde    22920     1 22364 15847  0 11:59 pts/22   00:00:04 /home/wilde/R/R-2.11.0/bin/exec/R --slave --no-restore --file=./SwiftRServ
> wilde    22760     1 22364 15847  0 11:59 pts/22   00:00:04 /home/wilde/R/R-2.11.0/bin/exec/R --slave --no-restore --file=./SwiftRServ
> bri$ 
> 
> 
> ----- "Mihael Hategan" <hategan at mcs.anl.gov> wrote:
> 
> > I can't tell what's causing the problem, but it may generally be a
> > good
> > idea to do a jstack -l when you get a hang.
> > 
> > Mihael
> > 
> > On Thu, 2010-09-16 at 12:14 -0600, wilde at mcs.anl.gov wrote:
> > > Mihael,
> > > 
> > > I've developed a Swift script that loops using iterate, reading
> > requests to process an R function from a named pipe (fifo), calling R,
> > and replying "done" on a response fifo.
> > > 
> > > This has been working very well, but I just hit a case where the
> > script hangs.
> > > 
> > > I exercise it using a small battery of R tests; I was manually
> > restarting the test battery (which does hundreds of R calls in 30
> > seconds or so, when it hung in the middle of the test suite.
> > > 
> > > As far as I can tell it hung after receiving a work request, mapping
> > the files for the work request, but never called the app() function
> > that invokes R.
> > > 
> > > The log is in ~wilde/rserver-20100916-1159-y94hftt0.log
> > > (I will try to post the script and all related files, but looks like
> > bridled may have just gone down for patches)
> > > 
> > > look for these trace lines in the log, which are issued at the start
> > of every R request:
> > > 
> > > line 37342:
> > > 
> > > 2010-09-16 12:03:24,212-0500 INFO  vdl:execute END_SUCCESS
> > thread=0-1-86-4 tr=bash
> > > 2010-09-16 12:03:24,213-0500 INFO  apply STARTCOMPOUND
> > thread=0-1-87-2 name=apply
> > > 2010-09-16 12:03:24,215-0500 WARN  trace SwiftScript trace: rserver:
> > got dir, /autonfs/home/wilde/SwiftR/SwiftR.run.233
> > > 2010-09-16 12:03:24,215-0500 INFO  SetFieldValue Set: done=false
> > > 
> > > The END_SUCCESS is the completion of the last app() in the prior
> > iterate pass, which signals the response ("done") fifo using a shell
> > script.
> > > 
> > > The trace says its starting to process the next R request, #233
> > (randomly assigned)
> > > 
> > > after mapping 20 files (for 5 R datasets containing 2 R evaluation
> > requests each)
> > > 
> > > it just hangs, and all I see in the log after that point is coaster
> > heartbeats.
> > > 
> > > The last request prior to this hanging request is in the log at line
> > 37137:
> > > 
> > > 2010-09-16 12:03:24,060-0500 INFO  vdl:execute END_SUCCESS
> > thread=0-1-85-4 tr=bash
> > > 2010-09-16 12:03:24,062-0500 INFO  apply STARTCOMPOUND
> > thread=0-1-86-2 name=apply
> > > 2010-09-16 12:03:24,062-0500 WARN  trace SwiftScript trace: rserver:
> > got dir, /autonfs/home/wilde/SwiftR/SwiftR.run.174
> > > 2010-09-16 12:03:24,062-0500 INFO  SetFieldValue Set: done=false
> > > 
> > > R request #174 (and all prior ones) completed fine, and should
> > illustrate the normal processing sequence.
> > > 
> > > Any ideas on what to look for regarding the cause of the hang?
> > > 
> > > I will try to reproduce it and try to get a karajan status trace
> > using swift stdin.
> > > 
> > > - Mike
> > >
>