gc new capacity of JVM is gradually reducing when webapp(tomcat) started
hi,all there is a problem with my webapp. by manual configuration, i allocated 1G(1024M) memory for webapp. where the gc new capacity automatically is 262M, the gc old capacity automatically is 699M, S0/S1 automatically is 43.6M/43.6M. When my webapp is started, I use the jvm's own tools(jstat) to trace the garbage collections. when the 6th Young garbage collection has happened, gc new capacity(262M) is gradually reducing. About 10 hours after, gc new capacity is only 40.6M. ##web operating environment: tomcat5.5.27 + Apache/2.2.3 + jdk1.5.0_13 + Linux_x86_64 ##blow is my manual configurations for tomcat JVM CATALINA_OPTS=-Xms1024M -Xmx1024M -Dorg.apache.jasper.compiler.Parser.STRICT_QUOTE_ESCAPING=false ##Jstat Tracking data (unit/k) systemTime --- S0C --- S1C --- S0U --- S1U--- EC --- --- OC --- OU --- YGC --- YGCT --- FGC --- FGCT --- GCT 10:03:10 --- 43648 --- 43648 --- 22444.3 --- 0 --- 262208 --- 217735.7 --- 699072 --- 163.6 --- 4 --- 0.126 --- 1 --- 0.007 --- 0.132 ##webpp startup 10:03:13 --- 43648 --- 43648 --- 22444.3 --- 0 --- 262208 --- 217735.7 --- 699072 --- 163.6 --- 4 --- 0.126 --- 1 --- 0.007 --- 0.132 : 10:11:35 --- 43648 --- 43648 --- 0 --- 22445.1--- 262208 --- 261516.6 --- 699072 --- 163.6 --- 5 --- 0.161 --- 1 --- 0.007 --- 0.168 ##5th YGC 10:11:38 --- 20800 --- 33984 --- 19898 --- 0 --- 258688 --- 4845.1 --- 699072 --- 163.6 --- 6 --- 0.192 --- 1 --- 0.007 --- 0.199 ##6th YGC, EC is reduced. : 10:18:41 --- 33152 --- 19968 --- 0 --- 19949.1--- 255232 --- --- 699072 --- 163.6 --- 7 --- 0.221 --- 1 --- 0.007 --- 0.228 ##7th YGC, EC is reduced. : 18:34:43 --- 640 --- 704 --- 608 --- 0 --- 40832 --- 58--- 699072 --- 87896 --- 380--- 5.413 --- 1 --- 0.007 --- 5.419 ##380th YGC, EC is reduced. this problem has been troubling me. please help ! -- Get the new Internet Explorer 8 optimized for Yahoo! JAPAN http://pr.mail.yahoo.co.jp/ie8/ - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
Re: gc new capacity of JVM is gradually reducing when webapp(tomcat) started
Hi, You could add a JVM runtime parameter like this : -Xmn256M to fix the size of new generation. Kind regards, Mercy 塗 wrote: hi,all there is a problem with my webapp. by manual configuration, i allocated 1G(1024M) memory for webapp. where the gc new capacity automatically is 262M, the gc old capacity automatically is 699M, S0/S1 automatically is 43.6M/43.6M. When my webapp is started, I use the jvm's own tools(jstat) to trace the garbage collections. when the 6th Young garbage collection has happened, gc new capacity(262M) is gradually reducing. About 10 hours after, gc new capacity is only 40.6M. ##web operating environment: tomcat5.5.27 + Apache/2.2.3 + jdk1.5.0_13 + Linux_x86_64 ##blow is my manual configurations for tomcat JVM CATALINA_OPTS=-Xms1024M -Xmx1024M -Dorg.apache.jasper.compiler.Parser.STRICT_QUOTE_ESCAPING=false ##Jstat Tracking data (unit/k) systemTime --- S0C --- S1C --- S0U --- S1U --- EC --- --- OC --- OU --- YGC --- YGCT --- FGC --- FGCT --- GCT 10:03:10 --- 43648 --- 43648 --- 22444.3 --- 0 --- 262208 --- 217735.7 --- 699072 --- 163.6 --- 4 --- 0.126 --- 1 --- 0.007 --- 0.132 ##webpp startup 10:03:13 --- 43648 --- 43648 --- 22444.3 --- 0 --- 262208 --- 217735.7 --- 699072 --- 163.6 --- 4 --- 0.126 --- 1 --- 0.007 --- 0.132 : 10:11:35 --- 43648 --- 43648 --- 0 --- 22445.1--- 262208 --- 261516.6 --- 699072 --- 163.6 --- 5 --- 0.161 --- 1 --- 0.007 --- 0.168 ##5th YGC 10:11:38 --- 20800 --- 33984 --- 19898 --- 0 --- 258688 --- 4845.1 --- 699072 --- 163.6 --- 6 --- 0.192 --- 1 --- 0.007 --- 0.199 ##6th YGC, EC is reduced. : 10:18:41 --- 33152 --- 19968 --- 0 --- 19949.1--- 255232 --- --- 699072 --- 163.6 --- 7 --- 0.221 --- 1 --- 0.007 --- 0.228 ##7th YGC, EC is reduced. : 18:34:43 --- 640 --- 704 --- 608 --- 0 --- 40832 --- 58 --- 699072 --- 87896 --- 380--- 5.413 --- 1 --- 0.007 --- 5.419 ##380th YGC, EC is reduced. this problem has been troubling me. please help ! -- Get the new Internet Explorer 8 optimized for Yahoo! JAPAN http://pr.mail.yahoo.co.jp/ie8/ - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
Re: gc new capacity of JVM is gradually reducing when webapp(tomcat) started
This says that the JVM is tuning its memory boundaries to best suit your application. Do you have any evidence that this is bad for your application? Or are you simply trying to find out why it is happening? - Peter 2010/4/21 塗 sesfei2...@yahoo.co.jp hi,all there is a problem with my webapp. by manual configuration, i allocated 1G(1024M) memory for webapp. where the gc new capacity automatically is 262M, the gc old capacity automatically is 699M, S0/S1 automatically is 43.6M/43.6M. When my webapp is started, I use the jvm's own tools(jstat) to trace the garbage collections. when the 6th Young garbage collection has happened, gc new capacity(262M) is gradually reducing. About 10 hours after, gc new capacity is only 40.6M. ##web operating environment: tomcat5.5.27 + Apache/2.2.3 + jdk1.5.0_13 + Linux_x86_64 ##blow is my manual configurations for tomcat JVM CATALINA_OPTS=-Xms1024M -Xmx1024M -Dorg.apache.jasper.compiler.Parser.STRICT_QUOTE_ESCAPING=false ##Jstat Tracking data (unit/k) systemTime --- S0C --- S1C --- S0U --- S1U--- EC --- --- OC --- OU --- YGC --- YGCT --- FGC --- FGCT --- GCT 10:03:10 --- 43648 --- 43648 --- 22444.3 --- 0 --- 262208 --- 217735.7 --- 699072 --- 163.6 --- 4 --- 0.126 --- 1 --- 0.007 --- 0.132 ##webpp startup 10:03:13 --- 43648 --- 43648 --- 22444.3 --- 0 --- 262208 --- 217735.7 --- 699072 --- 163.6 --- 4 --- 0.126 --- 1 --- 0.007 --- 0.132 : 10:11:35 --- 43648 --- 43648 --- 0 --- 22445.1--- 262208 --- 261516.6 --- 699072 --- 163.6 --- 5 --- 0.161 --- 1 --- 0.007 --- 0.168 ##5th YGC 10:11:38 --- 20800 --- 33984 --- 19898 --- 0 --- 258688 --- 4845.1 --- 699072 --- 163.6 --- 6 --- 0.192 --- 1 --- 0.007 --- 0.199 ##6th YGC, EC is reduced. : 10:18:41 --- 33152 --- 19968 --- 0 --- 19949.1--- 255232 --- --- 699072 --- 163.6 --- 7 --- 0.221 --- 1 --- 0.007 --- 0.228 ##7th YGC, EC is reduced. : 18:34:43 --- 640 --- 704 --- 608 --- 0 --- 40832 --- 58 --- 699072 --- 87896 --- 380--- 5.413 --- 1 --- 0.007 --- 5.419 ##380th YGC, EC is reduced. this problem has been troubling me. please help ! -- Get the new Internet Explorer 8 optimized for Yahoo! JAPAN http://pr.mail.yahoo.co.jp/ie8/ - To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org For additional commands, e-mail: users-h...@tomcat.apache.org
