too much time during GC process

[engcoder]

we are using the standard GC for java
for long time now we not do any changes to the GC thats why we attach the log file so you may something suspicious
my LS is of virsion 5.1.2
but i remind you that this problem was started from 2 days ago only but befor there was no problem and the GC was not take any time.

this is the LS.bat file portion

rem === CHECK THIS OUT
rem ================================================== =====================
rem JAVA_OPTS should contain any Java Virtual Machine options. Here are some tips:
rem 1) Always use the "-server" option.
rem 2) Give more RAM to the server process, especially with heavy traffic, by specifying a min and max "heap"
rem E.g.: If you have 4 GB and the box is dedicated to Lightstreamer, you might set 1 GB min heap and 3 GB max
rem heap with these options: "-Xms1G -Xmx3G"
rem 3) Choose a better "garbage collector" if you want to reduce latency. An option that often gives good results is:
rem "-XX:+UseConcMarkSweepGC". If you are using Java 7 (apart from early versions) or later, you might prefer to try:
rem "-XX:+UseG1GC". Many other tuning options are available (please see Oracle docs).
set JAVA_OPTS=-server -Xms6G

[giuseppe.corti]

Hi Ahmed,

From the log is evident the behavior of memory, which always repeats the same pattern, drops to approximately 4GB and then starts a major GC to recover approximately 2 GB; this takes several seconds (from 15 to about 1 minute).
This is behavior is not acceptable.

With a heap of 6GB we definitely recommends G1, and so I confirm to try the settings suggested above (rely on the default settings also makes you subject to possible changes of behavior).

That said, it is difficult say why the problem started just two days ago. Some updates at system level (SO updates, JVM change, ...)?
Some changes in memory usage (increase number of sessions, or the same number of sessions but with a increase in the frequency of updates, or larger size of the updates)?
The changes might be very small but have triggered a threshold effect.

Regards,
Giuseppe