[distcc] Cannot get distcc/pump to work

[John]

I have two Arch Linux machines on a GigaLAN both running the distccd package from the distro which is properly configured.  I can compile using just distcc without pump, but I cannot compile using pump and would love to figure out what's going wrong.

% systemctl status distccd.service

distccd.service - A distributed C/C++ compiler
  Loaded: loaded (/usr/lib/systemd/system/distccd.service; disabled)
  Active: active (running) since Wed, 2012-12-19 18:56:56 EST; 14min ago
    Docs: man:distccd(1)
Main PID: 6081 (distccd)
  CGroup: name=systemd:/system/distccd.service
  ├─6081 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6082 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6087 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6088 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6098 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6099 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6102 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6103 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6106 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  ├─6107 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log
  └─6110 /usr/bin/distccd --no-detach --daemon --allow 192.168.0.0/24 --log-level warning --log-file /tmp/distccd-x86_64.log

1) Workstation (Intel i7-3770K) with 8 logical CPUs.
2) Laptop (Intel C2D) with 2 logical CPUs.

On my workstation:
% cat /etc/distcc/hosts

localhost/9,cpp,lzo
192.168.0.102/3,cpp,lzo

On my laptop:
% cat /etc/distcc/hosts
localhost/3,cpp,lzo
192.168.0.101/9,cpp,lzo

Just the workstation:
% make -j8 bzImage  496.11s user 25.67s system 712% cpu 1:13.26 total

Trying to use pump/distcc

On the laptop...
% eval pump --startup

On the workstation...
% eval pump --startup
% pump make -j12 bzImage CC=distcc
__________Using distcc-pump from /usr/bin
__________Using 2 distcc servers in pump mode
make[1]: Nothing to be done for `all'.
  HOSTCC  scripts/basic/fixdep
  CHK     include/generated/uapi/linux/version.h

...

  CC      arch/x86/xen/setup.o
  CC      arch/x86/realmode/rm/video-vga.o
  CC      arch/x86/mm/fault.o
  CC      arch/x86/realmode/rm/video-vesa.o
distcc[25252] ERROR: compile arch/x86/realmode/rm/video-vesa.c on 192.168.0.102/3,cpp,lzo failed
distcc[25252] (dcc_build_somewhere) Warning: remote compilation of 'arch/x86/realmode/rm/video-vesa.c' failed, retrying locally
distcc[25214] ERROR: compile arch/x86/realmode/rm/video-vga.c on 192.168.0.102/3,cpp,lzo failed
distcc[25214] (dcc_build_somewhere) Warning: remote compilation of 'arch/x86/realmode/rm/video-vga.c' failed, retrying locally
distcc[25252] Warning: failed to distribute arch/x86/realmode/rm/video-vesa.c to 192.168.0.102/3,cpp,lzo, running locally instead
distcc[25214] Warning: failed to distribute arch/x86/realmode/rm/video-vga.c to 192.168.0.102/3,cpp,lzo, running locally instead
  CC      mm/mempool.o
distcc[25252] (dcc_please_send_email_after_investigation) Warning: remote compilation of 'arch/x86/realmode/rm/video-vesa.c' failed, retried locally and got a different result.
distcc[25252] (dcc_note_discrepancy) Warning: now using plain distcc, possibly due to inconsistent file system changes during build
  CC      kernel/panic.o
distcc[25214] (dcc_please_send_email_after_investigation) Warning: remote compilation of 'arch/x86/realmode/rm/video-vga.c' failed, retried locally and got a different result.
  CC      arch/x86/realmode/rm/video-bios.o
  CC      arch/x86/xen/multicalls.o
  PASYMS  arch/x86/realmode/rm/pasyms.h
  LDS     arch/x86/realmode/rm/realmode.lds
  LD      arch/x86/realmode/rm/realmode.elf
  RELOCS  arch/x86/realmode/rm/realmode.relocs
  OBJCOPY arch/x86/realmode/rm/realmode.bin
  AS      arch/x86/realmode/rmpiggy.o

...

  OBJCOPY arch/x86/boot/setup.bin
  BUILD   arch/x86/boot/bzImage
Setup is 17036 bytes (padded to 17408 bytes).
System is 3429 kB
CRC fa62427
Kernel: arch/x86/boot/bzImage is ready  (#10)
__________Warning: 3 pump-mode compilation(s) failed on server, but succeeded locally.
__________Distcc-pump was demoted to plain mode.  See the Distcc Discrepancy Symptoms section in the include_server(1) man page.
__________Shutting down distcc-pump include server
pump make -j12 bzImage CC=distcc  373.40s user 18.70s system 455% cpu 1:26.10 total