[rvm-research] Non-disturbing Segmentation Faults in Benchmarks

[Jan S. <su...@gm...>]

Hi,

1) I have noticed that using the -X:verbose option shows segmentation 
faults at a number of tests in different versions of Jikes. 
Specifically, I ran a test-run based on "perf" with just the extra 
argument -X:verbose and saw these faults in the perf-dacapo tests 
"eclipse" and "lusearch" and in the jbb-benchmarks. I double-checked the 
behaviour for the release 3.0.1 and (today's) trunk w.r.t. to the dacapo 
benchmarks. The system is running on an old Ubuntu 5.10 machine.
All tests run without problems in spite of these faults. Is this 
behaviour intended? I give two snippets of output below.
The first snippet is from running the perf-jbb2000 test. The signals all 
appear right after the message "Checking JVM" and continue in sequence; 
the last signal's output is depicted as well as some more lines; 
apparently, the actual test is only starting afterwards. However, I 
encounter an addittional "Loading Warehouse 1..." and the SPEC fair use 
policy near the end of the segmentation trace. (Might of course be 
because the err and out streams have been intertwined.)
The eclipse output has all other output except for the "PASSED in"  
_before_ the signals, and has a significantly higher number of these 
signals. (18m output file, see second snippet).

2) A less important question:  my own machine, a virtualized Ubuntu 8.10 
running on a IA-32 in Sun VirtualBox seems to be unable to perform I/O, 
failing with IOExceptions whenever a test needs data. I could be more 
specific on that is  nobody can tell of likewise behaviour. If have set 
777 access for all relevant directories that exist prior to the test. An 
Ubuntu 8.04 installation set up to compare the behaviour worked fine 
(but I am not sure whether or not this was before or after installing 
updates.) I have not collected these data.

Christian Sinschek,
Technische Universität Darmstadt

First Code Snippet:
------
JikesRVM: normal trap
failing instruction : mov ecx,dword ptr [edx-0CH]
Trap code is 0x0
Set vmr_fp to 0x686c8dcc
JikesRVM: trapped signal 11 (Segmentation fault)
handler stack 0x08063c78
si->si_addr   0xfffffff4
gs            0xc0100033
fs            0x00000000
es            0x0000007b
ds            0x0000007b
edi           0x9e72e520
esi -- PR/VP  0x5861f3d4
ebp           0x67c11014
esp -- SP     0x686c8db4
ebx           0x9e0a3fc8
edx           0x00000000
ecx           0x00000000
eax           0x00000000
ss            0x0000007b
eip           0x678a7cb3
cs            0x00000073
trapno        0x0000000e
err           0x00000005
eflags        0x00010202
fpstate       0x08063d90
oldmask       0x00020004
cr2           0xfffffff4
fp0 0x00000000000000000000
fp1 0x00000000000000000000
fp2 0x00000000000000000000
fp3 0x00000000000000000000
fp4 0x6000d0057e9d98534009
fp5 0x6000d0057e9d98534009
fp6 0x6000d0057e9d98734009
fp7 0x8000cfa2b166e3664001
JikesRVM: normal trap
failing instruction : mov ecx,dword ptr [edx-0CH]
Trap code is 0x0
Set vmr_fp to 0x686c8dcc

Input Properties:
  ramp_up_seconds = 30
  measurement_seconds = 120
  forcegc = true
  starting_number_warehouses = 1
  increment_number_warehouses = 1
  ending_number_warehouses = 12
jar validity is true


Checking whether run will be valid

Run will be COMPLIANT

Constructing the company now   Hang....on


++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

Loading Warehouse 1...




------------------------
Second Code Snippet
------------------------
JikesRVM: boot record contents:
   bootImageDataStart:   0x57000000
   bootImageDataEnd:     0x58c72000
   bootImageCodeStart:   0x5b000000
   bootImageCodeEnd:     0x5bc39000
   bootImageRMapStart:   0x5e000000
   bootImageRMapEnd:     0x5e06a000
   initialHeapSize:      0x19800000
   maximumHeapSize:      0x19800000
   tiRegister:           0x00040000
   spRegister:           0x584123a0
   ipRegister:           0x5b913150
   tocRegister:          0x57080288
   sysConsoleWriteCharIP:0x080512da
   ...etc...                   
JikesRVM: sysPthreadSelf: thread -1211214128
Using a time-slice of 20 ms
===== DaCapo eclipse starting =====
<setting up workspace...>
<creating 
projects..............................................................>
<running tests at level 0...>
<performing build tests...>
JikesRVM: trapped signal 11 (Segmentation fault)
handler stack 0x08063c78
si->si_addr   0x00000000
gs            0xc0100033
... ... ...
fp6 0x8800698286a9ba48c008
fp7 0x20001de89af9cbec4008
JikesRVM: normal trap
failing instruction : int 41H
Trap code is 0x1
Set vmr_fp to 0x69db1d44
===== DaCapo eclipse PASSED in 63799 msec =====