I am currently confusing how to optimize using HugePages with JVM applications with Netty, -XX:+UseLargePages option enabled, and using G1Gc. Also, I didn’t forget to set the same max and min size of the heap and metaspace. My application looks fine, but I was wondering what happens if there’s no …
Tag: jvm
The Intellij IDEA does not launch after editing the VM options file
In Intellij IDEA 2019 I mistakenly added incorrect lines to the VM option file (Menu | Help | Edit Custom VM Options). After that, the IDEA does not launch. Reinstallation didn’t help. When I run IDEA from terminal, it gives the following error: But at the same time, these lines are not in the idea64.vm…
How do jps, jinfo, jstat, jmap and jstack get information about local Java processes?
How does jps get information about all the local java processes? Does it connect to some local server process to fetch the information? How do jinfo, jstat, jmap, and jstack get information about a local java process? Do they connect to some local server process(es) to fetch the information? Is jstatd only us…
Does the JVM have an option to automatically encrypt it’s memory?
just like most packers(PE encryptor) on windows,for protecting the secret they may encrypt the whole process memory when it’s running. wonder if jvm has a memory encryption option we can choose? just thinking if someone dumped the whole JVM memory and he could get some secret info on text, even vi or gr…
Java – AttachNotSupportedException: Unable to open socket file: HotSpot VM not loaded
When attempting to attach an agent jar file onto another process running in java, I have came across the exception: com.sun.tools.attach.AttachNotSupportedException: Unable to open socket file: target process not responding or HotSpot VM not loaded I was running linux, with java Oracle JDK 8_101, however afte…
What is contained in code/internal sections of JCMD?
Dimensioning a docker container for a JVM based service is tricky (as we all know). I’m pretty sure we have slightly under-dimensioned a container and want to clear up a few questions I have relating to specific jcmd (Native Memory Tracker) outputs that we see when monitoring. Questions: Are Direct Byte…
Java1.5 ExitOnOutOfMemory?
I am having a problem making my java instance recognize command line CrashOnOutOfMemoryError or ExitOnOutOfMemoryError any ideas to get the supported command line that will do the required feature Regards, Answer Unless you’re using Java 1.8 (specifically, 1.8u92 or newer), these command-line options ar…
Eclipse error JVM terminated. Exit code=1 /usr/Java70/jre/bin/java
I get a error like My java version is: My eclipse.ini: Linux version: Why am I get that error and how can I solve it? Ran java -jar plugins/org.eclipse.equinox.launcher_1.3.0.v20130327-1440.jar Answer The problem was that whenever navigating to any workitem on RTC, that error occurred and eclipse crashed. Bas…
Does Java JVM use pthread?
Does JVM on Mac OS X use pthread to create threads? What about on Linux distributions, is it now default way to create threads for JVM on all distributions? Answer Yes, HotSpot JVM (i.e. Oracle JDK and OpenJDK) uses pthreads on Linux and on Mac OS X.
Unable to connect Serviceable Agent (sun.jvm.hotspot.HSDB) to running jvm on windows 7 (32 Bit)
As per the link I successfully be able to connect HSDB to running jvm process on Ubuntu by following steps below: (On Ubuntu Terminal) set SA_JAVA=/usr/lib/jvm/java-8-oracle/bin/java (On Ubuntu Terminal) echo 0 | sudo tee /proc/sys/kernel/yama/ptrace_scope (On Ubuntu Terminal) java -Dsun.jvm.hotspot.debugger.…