-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Sylvain,
On 5/5/14, 9:22 AM, Sylvain Goulmy wrote: > Thank you for your contribution to this thread. I think we we have > made good progress on the subject, here are some elements i'd like > to share : > > - The fact that the response time was increasing with the the > number of JSP loaded was linked to our monitoring tool... This tool > hadn't the same impact with websphere. Without monitoring the > response time remains stable no matter how many jsp are already > loaded in the permgen. Interesting. What monitoring tool are you using? > - There is no permgen defined in the IBM JVM running Websphere and > i was wondering how much space the JVM was allocating to host this > huge number of JSP. The memory footprint of the process on the > system was quite big : Xmx : 1,5 Go, memory footprint of the JVM : > 3,5 Go. It lets me think that Websphere allocates a large space to > host these JSP, i increase accordingly the permgen size of my JVM > to 1Go. If you aren't specifically setting the JVM's heap and perm gen sizes, then you are getting the defaults. If you are using Websphere, then Websphere is likely setting those defaults for you, rather than just getting the JVMs defaults. I can't remember if IBM JVM even has a perm gen space like HotSpot-based (Sun/Oracle) JVMs. > - I finally noticed that when the permgen is undersized (ie it > cannot host all the JSP of my application and has to unload class), > the CPU impact is much more important with the CMS garbage policy > than with the parallel GC. Remember that you can configure your JVM to have different GC policies for each heap space (e.g. permgen versus rest). > Our main concern so far was the CPU comsumption, we finally solved > this by tuning our monitoring tool correctly and by increasing the > size of the permgen. I'm interested in what that tool was doing... and why it didn't seem to have the same effect under Websphere... - -chris -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: GPGTools - http://gpgtools.org Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQIcBAEBCAAGBQJTZ6f8AAoJEBzwKT+lPKRYbxMP/R8+UJCkzEzYSZuwkT77PaIC KgUsh98UJylm2eUdmWqMAhBW0HiHgVz+tuhKPUVUnyOKaUCM2CvFx43sV8jjDfpF MiZP+ZdJFtbZ4/fW8zJ9Eg4v4bVJFfqDhIyfTU+wPGcRX/A88FQteyityYHdZqt7 nqHtGDCi2UMD2CC2TucL815ITRcu1Jyrwse3SJjv5k5d0kLJXP3R4JZgtPRwYBit ptdUq9QDuQLV3AhYak5gax9WvupVsMJrJSjHa8aw0HUR7fqJlCKYe+6IJlTAmyv1 x8Q5Ju3dCIigoaYcXfn0y+bpb0/DF4z9RoFiTA7p0mjViNkvYSL+RH7SYDJPbfDz Pe5QJPLdx+BxYPrq9XBAuTtgCRV2oefB5CnEMBUgm2tXqihMBmECS1ERYvo77vsh UUFkMUDannvsB6do4jQkIWr/i0RlSf40gHlDpnsTgmRO7kJM5fg9svBEMi2a3+Jo 4F7Ajjv7b8DYn4Dynh65P8VtwzFv3DKj14Mb5wUhXRkJFY0LpT4hUg999UGxEUq9 cBQ+txfg3A72Rbn/ShkVefZGLWrsp0zqYzFGqhBlpV2HDYiJb2PpYcMX8B6gl4ez nUBwt6qMHDsx6+jH6ug2EGrFcTbVAM5aidN+CZquivE9Bts20rsgupWmFZWMPeaB wNsNG70ARwUcyeryJBC/ =QUZb -----END PGP SIGNATURE----- --------------------------------------------------------------------- To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
