Questions tagged [multi-threading]
79 questions
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What causes Context Switching on Windows?
On Linux context switching can occur because an application makes a system call, or because the scheduler swaps processes out of the CPU for another process.
On Windows what are the possible causes of a context switch? Specifically, from the…
Q Boiler
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0 answers
Worker processes in Celery
I have a CPU intensive Celery task and within one of the task it can be further parallelized using joblib. By default, starting a worker with celery, will create a pool with number of max concurrency equal to number of CPUs/cores (which is 36 in my…
Coderji
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2 answers
Scaling Apache/PHP is as simple as maximizing the number of CPU cores?
I have an Linux/Debian server with Intel i7 CPU with 4 cores and 8 threads. When I run my heavy duty Apache/PHP job it uses 1 thread, and when I run concurrent Apache/PHP jobs they each use their own thread.
So, if I want to be prepared for high…
TheStoryCoder
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Apache 2.4 mpm_winnt: one thread takes all resources
I am working with Apache 2.4.33x64 on Server 2008 to run a site for max. 15 users. On the site you can do some really expensive calculations which can take some minutes (an external script is called).
During these calculations the server is on 15%…
1
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1 answer
Application caps at 20% utilization per core no matter how many threads are launched
I'm trying to use a Dell Poweredge R900 I got secondhand as a compute pool (4x quadcores gives me 16 cores to run simulations with). It's running windows server 2008 R2 enterprise at the moment.
I'm running custom .net code, and can specify the…
PhysicsNinja
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Why is method that uses gevent in a mod_wsgi deployed Flask api raising error about switching threads?
I am trying to deploy a Flask api via Apache/mod_wsgi. The api uses Gevent to provide concurrency for a recursive method. However, it is throwing the following error
[Mon Feb 08 12:05:37 2016] [error] error: cannot switch to a different thread
[Mon…
horcle_buzz
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1 answer
Use GPU to speed up server processing
I have a server that handles strings of data pushed from another server. Sometimes we receive thousands a second. This might be overly simplistic but would putting a Graphics card in the server assist in processing these strings quicker? Sometimes…
Display Name
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1 answer
uWSGI raises segfaults when defining several mount points in preforking+threaded mode
I'm hosting an application consisting of several Python modules. So far we use Apache in MPM worker mode and mod_wsgi, which is a working environment.
Now we want to check if nginx + uwsgi may be a more performant environment. Python is Python 2.6.6…
Ralph
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2 answers
redmine multitheaded
Our redmine server is not responding due to connecting it to a large repository. It has not crashed but it's just busy until it checks it out, or whatever redmine does when you set a new repo for a project. What is surprisning is that this operation…
xalpha
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Confusion about PHP Non-Thread safe
PHP 5.1.6 - Non-Thread Safe ( Thread Safety=disabled in phpinfo() )
Apache 2.2.3 - MPM prefork
Should I be using prefork or worker? If so is this an easy switch?
Robert
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PHP / SSH2 Multi-threading
I'm basically done using SSH2 with PHP. Some may already that while using it, the PHP code actually waits for all the listed commands to be executed in SSH and when everything is done, it then gives back the results. Where that is fine for the work…
Asad Moeen
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2 answers
Linux Scheduler (not using all cores on multi-core machine) RHEL6
I'm seeing strange behavior on one of my servers (running RHEL 6). There seems to be something wrong with the scheduler.
Here's the test program I'm using:
#include
#include
#include
void RunClient(int i) {
…
User512
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1 answer
Tomcat performing terribly for no apparent reason
We're running a game application .WAR on Tomcat 6 on an Amazon EC2 server, 8 core processor, 7gb RAM. The application uses a MySQL database hosted on Amazon RDS.
This Facebook application takes ages to access when a mere 20-30 users are playing it.…
John Hawthorne
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1 answer
Java doesn't seem to utilize more than two cpus
In my current setup (debian squeeze x64, 6 cpus) neither java nor apache seem to utilitze the full potential of the server. The munin monitoring shows cpu usage never exceeds the 200% mark. We ran several stress tests which raised the server load up…
Willi Schönborn
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3 answers
32 core multithreading performance for ASP.NET 4.0 and MS SQL 2008 Web Edition
Recently my user count has increased and my current server has started to become insufficient.
I am thinking about buying 4 x 8 = 32 core AMD CPUs using dedicated server. I wonder how good ASP.NET 4.0 and MS SQL 2008 Web Server is at…
Furkan Gözükara
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