Questions tagged [threads]
A thread is the smallest entity of execution within a program.
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Getting a per thread cpu stats
I'm interested in the current usage of cpu - precisely cpu% and wait% - for each thread in a specific application. Is it possible to get that information from somewhere?
I know that top can split ...
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19
votes
1
answer
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Apache 2.2 mpm_worker: more threads or more processes?
When using the Worker MPM in Apache, you can fiddle with the number of child processes and the number of server threads per child process.
What are the advantages and disadvantages of each? Under ...
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3
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How to get - number of threads per process?
This is one Ubuntu 9.10 server.
Also how to see memory usage per process?
Thanks
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9
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4
answers
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Virtualized CPU cores vs. threads
We've got a KVM host system on Ubuntu 9.10 with a newer Quad-core Xeon CPU with hyperthreading. As detailed on Intel's product page, the processor has 4 cores but 8 threads. /proc/cpuinfo and htop ...
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1
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what does apache (busy workers , idle workers) means?
what is the meaning of Apache busy workers and idle workers? how the statistic of them help me to figure out performance problem with my server?
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Multithreading with multi-queue NIC on SMP system [closed]
How are packets scheduled from network interface queues to CPUs, then onwards to threads for processing? What needs to be considered when it comes to how packets are hashed across queues, hardware ...
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3
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Java: Limit the number of cores a JVM can use
Multiple users are running java applications on a 60-core compute server (Linux/Ubuntu-based). There are different applications and most of them are not developed in-house.
While the sysadmin thinks ...
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1
answer
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Python Threads and uWSGI Harakiri
I have a webapp that is using an API built on nginx, uWSGI, and Django. Recently I have been seeing a lot of harakiris on a particular API call which does some quick processing and then spawns a few ...
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2
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Nginx worker_processes and multi core cpu's - Do Hyper-threading cores count?
Quite often, when reading about the recommended worker_processes for nginx it is stated that this should be set to the numbers of cores the server hosting nginx has.
We were wondering if we should ...
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6
votes
1
answer
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Enabled hyperthreading - causes qthread creation error on Ubuntu Precise 64 bit
We recently set up an HP ProLiant DL360p server for some heavy grunt-work. For one reason or another we disabled hyperthreading in the system BIOS when setting it up. Being a dual-CPU 8-core system, ...
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2
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Can I have multiple threads running in parallel in a pod with a CPU limit set to 500 millicores?
I have a multi cores Kubernetes cluster, inside it I have multiple pods configured with a CPU limit of 500 millicores:
resources:
limits:
cpu: "500m"
It is ...
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votes
1
answer
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Limit the number of max threads used by a process in linux kernel
I think I have found something that I need from the Linux kernel that is not currently implemented.
I need a way to set a max thread limit per process.
Is this possible?
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votes
2
answers
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debugging stuck apache/php thread on production server
I have a linux system with apache httpd and PHP which is loaded using LoadModule php5_module /usr/lib/apache2/modules/libphp5.so.
I've enabled the mod_status module of apache and I see a particular ...
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1
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Increasing FreeBSD threads
For network apps that create one thread per connection (like Pound), threadcount can become a bottleneck on the number of concurrent connections you can server.
I'm running FreeBSD 8 x64:
$ sysctl ...
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What is optimal IIS threading settings for a Win2012 server that does lots of slower web service calls?
We have a Windows 2012 Server that communicates to lots of other services via SOAP based web services using ASP.Net and .NET 4.5. These services tend to have higher latency (i.e. 2-6 seconds to ...
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0
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How do I reduce the threads per process limit for an ISAPI app under IIS 7.5
I have a python WSGI application running under an ISAPI extension in IIS 7.5 on Windows Server 2008. I would like to increase the number of worker processes (which I know how to do) and reduce the ...
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3
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Why having more and faster cores makes my multithreaded software slower?
I am experiencing bizarre behavior on scaling a multiprocess/multithreaded C++ application. The application contains 10 separate processes, communicating through Unix Domain Sockets and each one ...
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votes
1
answer
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Tomcat threads are increasing but never decreasing
We are using new relic to monitor tomcat threads. The graph shows increase of thread count,but it never decreased even the application is idle. We noticed that when it increase CPU also increased and ...
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votes
1
answer
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Tell Tomcat to drop requests instead of dying "All threads (150) are currently busy"
My Tomcat 6.0.26 sometimes dies saying:
SEVERE: All threads (150) are currently busy, waiting. Increase
maxThreads (150) or check the servlet status
... then Tomcat shuts down, and users can't ...
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3
votes
4
answers
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Can Windows be configured to only use a single hardware thread?
Is is possible to configure Windows to only use a single hardware-thread. Every machine for the last couple of years seems to be at least dual-core, but some timing bugs are only reproducible when ...
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2
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Stand alone single thread optimized server vs vm running on VMWare
I apologize for the length of my post.
We recently converted our business system to a product that is licensed by the number of Cores.
We purchased the 2 core license and are currently running it on ...
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votes
2
answers
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How do I increase the queue length in IIS's default app pool via command line?
I have a farm of IIS servers running Exchange and we are getting this error in HTTP Error:
HTTP/1.1 POST /ews/exchange.asmx - 1 Connection_Dropped_List_Full MSExchangeServicesAppPool
The advice from ...
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2
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My linux server "Number of processes created" and "Context switches" are growing incredibly fast
I have a strange behaviour in my server :-/. Is a OpenVZ VPS (I think is OpenVZ, because /proc/user_beancounters exists and df -h returns /dev/simfs drive. Also ifconfig returns venet0). When I do cat ...
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2
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Does anyone know where I can find "proof" that SQL's Fiber mode is barely faster than regular thread mode on Win 2008 R2
I remember seeing a PDC presentation on the Windows Kernel regarding Threads vs Fibers and in it Mark R. mentioned that this caused SQL's Thread mode to run almost as fast as Fiber mode, but with ...
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1
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Linux kernel thread dependency graph?
I'm trying to benchmark a system with a software RAID-10 volume, backed by Fusion IO cards. Is it possible to display a Linux kernel thread dependency graph?
I would like to know how all the [xfs],...
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votes
2
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Hang while starting several daemons
I’m running a Debian Squeeze AMD64 server. Target runlevel after boot is runlevel 2, which includes rsyslogd, cron, sshd and some other stuff, but not dovecot, postfix, apache2, etc. The system fails ...
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2
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Redhat 5.5: Multi-thread process only uses 1 CPU of the available 8
Weird situation:
Redhat Enterprise 5.5 (stock install, no updates, x64) on a HP z800 workstation.
(Dual Xeon 2,2 Ghz. 8 cores, 16 if you count Hyper-threading. RH sees 16 cores.)
We have an ...
- 6,352
2
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1
answer
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PHP Threading on Gentoo
PHP on Gentoo supports the threads USE flag. As far as I know, PHP does not support true threading; I am only aware of the ability to fork using pcntl_fork(), but this functionality is provided by the ...
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1
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httpd - Increase number of concurrent requests
I have httpd server running on Centos7. The apache details - Apache/2.4.6 (CentOS) OpenSSL/1.0.1e-fips PHP/5.4.16
I'm trying to load test a web application by starting to hit it with 100 users & ...
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Does Apache ever give incorrect "out of threads" errors?
Lately our Apache web server has been giving us this error multiple times per day:
[Tue Apr 06 01:07:10 2010] [error] Server ran out of threads to serve requests. Consider raising the ThreadsPerChild ...
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1
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Give pthread_setschedparam() permissions to non-root user (linux)
How can I give a non-root user permission to execute pthread_setschedparam() to set thread priorities?
Thank you
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3
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freebsd 7.2 kern.threads.max_threads_per_proc doesn't change after reboot
I have some multithread apps on my server machine based on FreeBSD 7.2, so because of this I need to increase kern.threads.max_threads_per_proc to 4000 (default value is 1500).
I changed it using "...
2
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2
answers
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MariaDB threads optimalization
NEW (pcie) server:
Intel(R) Xeon(R) CPU E5-2637 v4 @ 3.50GHz, 1TB NVMe disks, 128 GB RAM, installed Debian 4.9.65-3+deb9u1, Ver 15.1 Distrib 10.1.26-MariaDB
moved binary db files from
OLD server:
...
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Mysql single connection share by multiple java thread?
I have a java application with multiple thread started and they are all sharing a single db connection created in the main function. So far things have been running smoothly. I am worried will there ...
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3
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Optimal number of threads for compute-intensive task on server with Hyperthreading
When running a compute-intensive task on a server with an Intel i7 quad-core processor with Hyperthreading, is it ideal to run eight threads (for the eight virtual cores), or only four (for the four ...
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Apache stopped working permanently after error "Server ran out of threads to serve requests."
I have been working with Apache for more than 8 years, but now I'm facing a severe problem and I couldn't find a solution on internet so far.
I'm running Apache 2.2.15 32bit on a Windows 2008 R2 ...
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0
answers
216
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DNS doesn't resolve some domains on huge amount of requests
I need to check 200kk (200,000,000) domains for availability and CMS information.
I'm using php 7.1 and simulating multi-thread check.
Hardware and config
The server hardware: Multicore CPU, 64GB ...
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votes
1
answer
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Incorrect CPU thread numbering detected
I've procured an HP DL360 G7 second hand. I'm wondering if this is either a fault in the OS or the hardware.
Installed are 2X Intel Xeon X5650 CPUs, each with 6 cores with threading enabled. Logic ...
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votes
0
answers
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How does a server (e.g. web) manage multiple request/connections? [closed]
I read that apache has a solution to create new thread per new request, but I still have some questions.
How is possible that one server can manage thousands (even a milion connection - depends from ...
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What is a fast, efficient method for threading rsync
I have a single root directory (on a NAS) that I need to backup to another server. The hierarchy of the directory is several layers deep and a majority of the data is composed of extremely large ...
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determine if threads on a cpu are blocked? What are the causes of thread blocks?
The load-average reported by uptime command also displayed in top provides the the average run-queue length over time (1, 5 and 15 minutes)
The run-queue length is the sum of the number of threads (...
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0
answers
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IIS Worker Process Thread Count
I've seen this question asked but the answer given was either insufficient or unrelated. I feel like this is a pretty simple question(s).
We have a Classic ASP app running on IIS7.5 on a Windows 2k8 ...
2
votes
0
answers
2k
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How to tell uWSGI to prefer processes to threads for load balancing
I've installed Nginx + uWSGI + Django on a VDS with 3 CPU cores. uWSGI is configured for 6 processes and 5 threads per process. Now I want to tell uWSGI to use processes for load balancing until all ...
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votes
0
answers
191
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Apache worker mpm, one process and many threads: understanding performance
Got a mod_perl-written serverside program.
Im using shared apache worker mpm memory with one process only, and ~ 60 threads.
Im using locks to temporary secure the access to the shared memory, just 0....
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3
answers
756
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Mysql Replication - are per-database threads possible?
I manage a MySQL server hosting over 100 databases.
We have set up standard master-slave replication, but the SQL Thread tends to break every so often, and requires manual intervention to re-start ...
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5
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How many simultaneous requests would you expect a webserver to handle
I know there is no straight answer to this question - depends on specs etc. But what is the order of magnitude of simultaneous requests you'd expect a server to handle?
Currently, our server starts to ...
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1
answer
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MariaDB / MySQL using a lot of threads / memory
I've been setting up a new VPS and wanted to try out MariaDB. I'm using MariaDB 10.0.1, which as far as I understand it is the equivalent of MySQL 5.6.
Has the thread handling of threads changed ...
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vote
2
answers
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How to make the most of JBOSS in multicore environments
I'm deploying jboss in a multicore system, where I'll have from 12 to 20 cores, and when I run the jboss server, I only see 1 process running, and I feel like it won't use more than one core...
Is ...
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vote
1
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NUMBER_OF_PROCESSORS env var incorrect on Dell PowerEdge Gen14 With Windows Server 2012 R2
I'm seeing that the environment variable NUMBER_OF_PROCESSORS is incorrect on my newly installed Dell PowerEdge 740xd Gen 14 running Windows Server 2012 R2 Standard.
The machine contains 2 CPUs - ...
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1
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Windows Server 2012 R2 kernel threads increase until the system hang
I have a small problem with my Windows Server 2012 R2. At the moment the problem is that the threads from "NT Kernel & System" increase every second until they reach 16k, and then the server ...
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