rich.fromm wrote: > > Small scale individual tests work fine. When I try executing larger > scale stress tests that include multiple concurrent requests to tomcat, > things > run fine for a while, but eventually the JVM crashes and tomcat dies. > <...> > I have not yet been able to > reproduce a single failure -- I'm still working on it. But if this is a > threading issue, I may not be able to get a reproducible test case. >
I was on the verge of completely blaming threading, but now I'm not so sure. I have had two more crashes, see #5 and #6 below. (#1 through #4 are in the original mail.) #5 looks to be identical to #3 and #4. And all of #1 through #5 occurred when tomcat was potentially handling multiple concurrent requests. In no case have I been able to reproduce the exact failure, even when playing back requests that I think were the trigger of the failure. Which seems to point to a threading problem. But in crash #6, I had the client waiting until a request returned before making another request. So tomcat was invoking mapserver purely sequentially, and I would have thought that threading problems were not an issue. Nevertheless, eventually the server crashed, and once again if I replay the exact request that triggered the failure, I can not reproduce the crash. So I fear that it's going to be very hard for me to create a reproduceable test case for this, but inevitably if I throw enough requests at mapserver, it always crashes and brings down tomcat, usually within about an hour or two. - Rich --- crash #5: (msFreeLabelCacheSlot) mapfile.c:4068 (msFreeLabelCache) mapfile.c:4100 (msFreeMap) mapobject.c:98 (delete_mapObj) mapscript/java/mapscript_wrap.c:1619 (Java_edu_umn_gis_mapscript_mapscriptJNI_delete_1mapObj) mapscript/java/mapscript_wrap.c:19695 crash #6: (msImageCreateWithPaletteGD) mapgd.c:3471 (msSaveImageBufferGD) mapgd.c:3697 (msSaveImageBufferAGG) mapagg.cpp:2248 (msSaveImageBuffer) maputil.c:688 (imageObj_getBytes) mapscript/java/mapscript_wrap.c:2486 (Java_edu_umn_gis_mapscript_mapscriptJNI_imageObj_1getBytes) mapscript/java/mapscript_wrap.c:24414 -- View this message in context: http://www.nabble.com/thread-safety-tp15514019p15562378.html Sent from the Mapserver - User mailing list archive at Nabble.com. _______________________________________________ mapserver-users mailing list mapserver-users@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/mapserver-users