FAQ Database Discussion Community

How to limit the CPU usage of a dash loop that listens for a filesystem change?

I wrote a loop in dash which waits for a file to appear in a certain location on the filesystem. But when it runs it takes up 50% of the CPU. I first lowered the CPU usage using a sleep command but the minimal sleep time in dash (1 second)...

How can get memory and CPU usage of hadoop yarn application?

I want to ask, after I've ran my hadoop mapreduce application, how can I get the total memory and CPU usage of that application. I've seen it on log and resource manager web page but I didn't get it. Is it possible? Can I get it per job execution or...

TaskManager android that will show current memory usage and cpu usage

I am making a Project on TaskManager android just like windows Taskmanager. How to get CPU usage and memory Usage?

What is the theoretical impact of direct index access with “high” memory usage vs. “shifted” index access with “low” memory usage?

Well I am really curious as to what practice is better to keep, I know it (probably?) does not make any performance difference at all (even in performance critical applications?) but I am more curious about the impact on the generated code with optimization in mind (and for the sake...

How to get CPU usage of certain function in android app?

I'm trying to get CPU usage in some point of running app. I need something like i used for time measurement. Before I called the function (witch I want to measure) I used System.currentTimeMillis() to get the start time and the difference with the same value after function ended. Running...

mpi cpu usage doesn't make sense

My windows system has 8 cores. When I use 8 CPUs with my MPI: mpiexec.exe -n 8, all of my 8 available processors are busy in task manager which makes sense. When I use 2 cores: mpiexec.exe -n 2, I expect only 2 cores should be busy but that's not...

How to fully take advantage of multi-cores by python

I used python to execute this program on Ubuntu import thread import time # Define a function for the thread def print_time( threadName, delay): count = 0 while True: count += 1 # Create two threads as follows try: for index in xrange(1,50000): thread.start_new_thread( print_time, ("Thread-" + str(index), 0, )...

Number of threads to limit CPU usage

My application is a thread-per-request web server with a thread pool of M threads. All processing of a single request runs in the same thread. Suppose I am running the application in a computer with N cores. I would like to configure M to limit the CPU usage: e.g. up...

Linux echo cpu (core) name/number for a given shell in PBS

I have a simple C++ code that uses Intel's TBB to run a list of scripts on a cluster using PBS. I want to confirm that I am using all the cores as intended. Each node has 16 cores. I have created the scripts to take varying amounts of time...

How to write an array to a file?

I try to write a short script what will count average value for CPU for last XY minutes. I wrote something like that (just short overview). First part of the script just stored values in tmp file. From this values is count avg value: $CPU= ........ Add-Content "myfile.txt" "$CPU" $array=(Get-Content...

Using Cgroups to limit cpu usage

I am trying to use cgroups in order to limit the CPU usage. I am using this guide https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Resource_Management_Guide/sec-cpu_and_memory-use_case.html My /etc/cgconfig.conf file is the following mount { cpu = /mnt/cgroup/cpu,cpuacct; cpuacct = /mnt/cgroup/cpu,cpuacct; } group wheel { cpu { cpu.shares="800"; } cpuacct { cpuacct.usage="0"; } } group test1 { cpu...

How to monitor and/or throttle rate limit cpu/bandwidth by client-side web pages?

Nowadays it appears that many webpages want to use my cpu/harddrive/bandwidth in order to show me their ads/pages/information in beautiful but expensive ways. Often I like these new pages, but sometimes I'm a curmudgeon and am just annoyed that my fan starts spinning and the EMF loads rise when I...

Websites use server or client hardware resources?

When a user visits a website which runs an intensive script, does the web server handle it by using its own CPU and RAM, or does it use the users' resources?

Debugging Java application causes high cpu utilization

When I'm debugging my Java EE application on Weblogic from Eclipse, in some cases just the fact that the debug is connected and enabled, causes high CPU utilization. The moment that I disconnect from debug port, the CPU utilization drops to normal levels. What can cause it and how can...

How to interpret CPU time vs CPU percentage

When I check azure monitoring tool, CPU usages are shown in CPU time min: 4.69s max: 2008.08 s avg : 207.63 s I am familiar with CPU% which makes sense as in application requiring cpu cycles. how does the above time correspond to percentage? What would be the max in...

CPU usage is extremly high due to mysql process

I have a godaddy VPS box with 4 GB RAM. It has only 1 website hosted with nearly 800-1000k hits perday. upon investigation i found that my cpu usage is some times goes above 100%. The below mysql process is the culprit. Can some one help me. I have tried...

Efficiency of running many more jobs than CPUs

I have a large set of jobs to run (thousands), each one takes between 30 minutes to a few hours on a single CPU. The memory requirements are small (few KB each). I'm working on a small linux cluster that has a few dozen CPUs. So far, I've been starting...

MySQL query runs ok in phpadmin but hangs in php

I have a fairly simple query which runs okay when I test it in phpMyAdmin: SELECT c.customers_id, c.customers_cid, c.customers_gender, c.customers_firstname, c.customers_lastname, c.customers_email_address, c.customers_telephone, c.customers_date_added, ab.entry_company, ab.entry_street_address, ab.entry_postcode, ab.entry_city, COUNT(o.customers_id) AS orders_number, SUM(ot.value) AS totalvalue, mb.bonus_points FROM orders AS o, orders_total AS ot, customers AS c, address_book AS ab, module_bonus AS...

how to join 2 queries into 1

I am trying to join 2 of the following queries select * from MapCountries where IndexName='SPX Index' and date(ModifiedDate)='2015-04-24'; select DRegion,DCountry,GICS1,GICS2,LRY,BBGLableValues from CompanyDetails where IndexName='SPX Index' and CompanyTicker='A UN' and date(ModifiedDate)='2015-04-24'; the second query is fired from the "while(reader.read())" of the first query. This is taking up a lot of...

C linux regex performance issue

I'm creating a program that reads file line by line, match that line to regex and diplay how many lines has matched that regex. The problem is, this program is using pretty great precentage of CPU. 67.5% without valgrind and with valgrind 100.1% and it's very slow ~5 seconds for...

Visual VM: how to interpret Self Time vs Self Time (CPU)

I already read VisualVM and Self Time But I still don't get how to interpret. Here is my case : Self Time : 500000ms Self Time (CPU) : 72000ms I understand that the method took 72s of CPU execution time (So real work without sub-method called). Can I interpret that...

How to extract CPU Usage details from the log file in logstash

I am trying to extract the CPU usage and timestamp from the message: 2015-04-27T11:54:45.036Z| vmx| HIST ide1 IRQ 4414 42902 [ 250 - 375 ) count: 2 (0.00%) min/avg/max: 250/278.50/307 I am using logstash and here is my logstash.config file: input { file { path => "/home/xyz/Downloads/vmware.log" start_position => beginning...

Tomcat not using all cores in high load period

We have a strange behaviour with our tomcat server. Initial situation: tomcat-server with 50 webapps (spring applications delivering websites using thymeleaf template engine) server with 16 cores and 96GB ram jmeter for load-testing against one webapp, others idling 120 threads 10 repeats http requests against a bunch of urls When...