0
votes
0answers
20 views

Why first-time reading file from hdd is slower then next ones? [migrated]

I am measuring my HDD speed with a self-written program. (This is a sort of homework, so I don't need recommendations about existing tools to do that). I do it with the following piece of code: ...
1
vote
1answer
95 views

How does it harm if I install JDK on my ubuntu server when JRE is just enough for me?

I just need JRE for my programs. But how does it harm if I use JDK when JRE is enough for my webserver? Does it only mean more harddisk space for JDK & except for that, no other waste? I use ...
2
votes
1answer
80 views

Why would disk reads be heavier than writes with a simple java app that creates many small files?

I've got a very simple java 7 app that reads from a proprietary file format (Hadoop sequencefile) sitting on disk xvdb and creates millions of 2-20kb files on disk xvdf. ByteBuffer byteBuffer = ...
0
votes
1answer
2k views

Weblogic intensive CPU usage

I am using Weblogic 10.3.4 + Oracle DB both on Solaris machines (VM) Unfortunately last week our app hosted on Weblogic became very very slow not being able to serve new users coming (everything ...
0
votes
0answers
208 views

Incredibly slow response when reading from mounted Windows shared network drive within Java application

I wrote a Java application that checks and indexes huge archive files. When i test it on my local machine, everything is speedy and works like a charm. However, i need to process large quantities of ...
9
votes
5answers
678 views

How do I find the cause for a huge difference in performance between two identical Ubuntu servers?

I am running two Dell R410 servers in the same rack of a data center (behind a load balancer). Both have the same hardware configuration, run Ubuntu 10.4, have the same packages installed and run the ...
2
votes
3answers
1k views

CPU/JVM/JBoss 7 slows down over time

I'm experiencing performance slow down on JBoss 7.1.1 Final. I wrote simple program that demostrates this behavior. I generate an array of 100,000 of random integers and run bubble sort on it. ...
1
vote
1answer
1k views

Oracle 11. Updating BLOB field. Db file sequential read inappropriately slow?

I've and Oracle (11 Enterprise) schema with a table CREATE TABLE USER.WSP_BUNDLE ( NODE_ID RAW(16) NOT NULL, BUNDLE_DATA BLOB NOT NULL ); CREATE UNIQUE INDEX USER.WSP_BUNDLE_IDX ...
1
vote
1answer
332 views

Performance factors in remote database access

I have a Java application which accesses a database. I tested it on my local machine with local database and it works just fine. But when I test it in our test environment where the application server ...
3
votes
3answers
694 views

Apache/Tomcat Parameters

I have a Medium server on EC2. I don't know that much about Apache or Tomcat - they are up and running, but other than that I don't have advanced knowledge of how to tinker. I know that I can set the ...
1
vote
2answers
1k views

Performance issue on solaris 10 zone. Multiple pollsyscalls

We have slow running JAVA program on a Solaris 10 Zone. I ran a truss on the pid and noticed following messages getting generated even when program is not doing anything: pollsys(0x00000000, 0, ...
-2
votes
3answers
136 views

who is responsible for server monitoring? [closed]

who is responsible for server monitoring ? development team ? development team leader ? Project manager ? dba ? infrastructure team ? who is responsible when application server is running slow or ...
4
votes
2answers
2k views

Performance problems when running Java desktop applications on Citrix Metaframe

We have a desktop Java application running within a Citrix Metaframe server farm and the performance, specially while starting up the app, is very unreliable. Sometimes it takes 15 seconds and ...
1
vote
1answer
1k views

jvm performance tuning tips / resources?

My experience with the jvm has mostly been maintain a tomcat container for several applications. I find myself always not sure of the what ratio of -Xms -Xmx -Xmn -XX:PermSize -XX:MaxPermSize ...
4
votes
3answers
1k views

Fastest Open Source Java Application Server

Which Open Source Java Application Server is the fastest? Glassfish Jetty JBoss Others?
-1
votes
3answers
823 views

What are the best linux performance tweaks for javac without a makefile?

What are the best linux performance tweaks for javac without a makefile? I am talking about the use of ant build files and IDEs that scan the source and create the dependencies as well as doing the ...
0
votes
4answers
179 views

Testing Java performance

There are a handful of different standard desktops and laptops at my company that I could choose from for developers on my team. Each is from a different company and comes with different load-outs of ...