Unfortunately, as I just discovered, older versions of Pharo do not
support UFFI. I don't have the time (nor a real interest) in backporting
the code to an older pre-Spur VM which has probably reached its EOL just
for the sake of experimentation. It would probably take hours to
understand the older FFI model and to adapt the code for no real advantage.
The current Pharo VM seems to support only the --memory option: I tried
with 1 and 2 GiB, nothing changes in the misbehavior.
I also tried the two heap-related JVM options in isolation,
unsuccessfully. Just for information, the current values for the options
are -Xms16m and -Xmx512m, meaning that the JVM heap should start with 16
MiB and grow to a maximum size of 512 MiB, both of which are rather
modest values even for a 32 bit process. Besides, they work in
VisualWorks (32 bit).
The StackOverflow page indicated below is from year 2010, during the age
of Java 6. The JVM has undergone major changes since then, including
memory management, so I'm not sure the discussion there is relevant for
Java 8, the release we are targeting as of today. But even if it were, I
still cannot understand the crash in Pharo.
On 2017-05-03 06:36, Ben Coman wrote:
On Wed, May 3, 2017 at 12:30 AM, Denis Kudriashov <[email protected]
<mailto:[email protected]>> wrote:
Could you check how it works with Pharo5 which was based on prespur
CogVM?
Note, Pharo 5 Release was a Spur VM.
Try using...
http://files.pharo.org/get-files/50-preSpur/
http://files.pharo.org/image/50-preSpur/50495.zip
or even Pharo 4.
cheers -ben
2017-05-02 16:36 GMT+02:00 Raffaello Giulietti
<[email protected]
<mailto:[email protected]>>:
Hello,
I'm on Pharo 6 (32 bit)/Windows 10 (64 bit).
I'm trying to load and use the (32 bit) JVM DLL into a running
Pharo image via the UFFI.
Everything works correctly, including JVM method invocations,
except when trying to set the minimum and maximum JVM heap size
by passing the -Xms<size> and -Xmx<size> options upon JVM
creation. With these options, Pharo simply crashes without
leaving any trace.
Can you isolate whether the problem is either one of those, or it
happens with both, and if there is some cutoff where it works? Also,
perhaps try limiting heap being used by Pharo
--memory <size>[mk] use fixed heap size (added to image size)
--mmap <size>[mk] limit dynamic heap size (default: 1024m)
[out 2G on 32-bit)
--maxoldspace <size>[mk] set max size of old space memory to bytes
(disclaimer, I'm not too knowledgeable on these, just pulled them
from --help)
Also consider that heap needs to be contiguous...
**http://stackoverflow.com/questions/2457514/understanding-max-jvm-heap-size-32bit-vs-64bit
cheers -ben
Apparently, memory management requests from the JVM interfere
with Pharo's own memory management.
Please note that we successfully use the same mechanism for both
VisualWorks (32 bit)/Windows 10 (64 bit) and Gemstone 64
bit/Linux, so it seems it has to do with a Pharo limitation somehow.
Further, I couldn't find any documentation on how to increase
Pharo's working set.
So the questions are:
* What is the most probable cause of the crash described above?
* Where is there more doc about Pharo's memory configuration
settings?
Greetings
Raffaello
