A thread is the smallest entity of execution within a program.

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13
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1answer
4k views

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 ...
9
votes
3answers
14k views

How to get - number of threads per process?

This is one Ubuntu 9.10 server. Also how to see memory usage per process? Thanks
6
votes
1answer
669 views

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, ...
5
votes
0answers
1k views

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 ...
4
votes
4answers
8k views

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 ...
3
votes
4answers
596 views

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 ...
3
votes
5answers
6k views

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 ...
3
votes
1answer
6k views

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?
3
votes
2answers
207 views

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 ...
3
votes
1answer
57 views

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 ...
3
votes
1answer
825 views

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 ...
3
votes
2answers
2k views

Hang while starting several daemons [solved]

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 ...
3
votes
2answers
2k views

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 ...
3
votes
1answer
1k views

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 ...
2
votes
1answer
1k views

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?
2
votes
1answer
391 views

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 ...
2
votes
2answers
2k views

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 ...
2
votes
1answer
786 views

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 ...
2
votes
2answers
410 views

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 ...
2
votes
1answer
816 views

check CPU affinity of process and it's threads

How do I check CPU Affinity for a linux processes and all of it's threads?
2
votes
2answers
473 views

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 ...
2
votes
0answers
70 views

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 ...
2
votes
3answers
584 views

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 ...
1
vote
1answer
2k views

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 ...
1
vote
2answers
1k views

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 ...
1
vote
1answer
2k views

IBM Websphere Application Server 7 - Why aren't threads that are hung destroyed?

If our application somehow loses connection with the memcached server all the threads are reported as hung after 10 minues or so [28.04.11 16:50:15:831 CEST] 00000025 ThreadMonitor W WSVR0605W: ...
1
vote
2answers
2k views

JRun threadpool configuration

Me and my team have been struggling to keep a clustered ColdFusion application stable for the better part of the last 6 months with little result. We are turning to SF in the hope of some finding ...
1
vote
3answers
75 views

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 ...
1
vote
1answer
573 views

Mysql thread eating up the whole cpu

I have a problem with MySQL server. Some mysql thread for a few hours eating up the whole processor. Killing the process certainly helps, but how is it possible to track that the code is running ...
1
vote
1answer
207 views

is Apache MPM prefork ALWAYS single threaded?

My impression is yes that it is and that this is why mod_php shops run it (usually for non-thread safe apps). On my ubuntu box, if I run sudo ps axo pid,ppid,rss,vsz,nlwp,cmd I get this: 32305 ...
1
vote
1answer
667 views

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
1
vote
1answer
605 views

Is linux kernel 2.6.37 80% slower than 2.6.34 using memory & threads?

If I run the command time perl -e 'use threads; $T=12 ; foreach (1..$T) { $thr[$i++] = threads->create(sub { printf "I am thread %s\n", threads->tid(); foreach (1..9e6) { push(@a, ...
1
vote
1answer
418 views

Changing memory allocation policy on Linux

How can I change memory allocation policy on Linux? On Solaris it's done system-wide with lgrp_mem_default_policy (man page) and pmadvise (man page) is a per process equivalent that does not require ...
1
vote
0answers
118 views

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 ...
1
vote
0answers
311 views

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 ...
1
vote
0answers
97 views

IIS 7 configuration does not lead to expected performances/thread count

I have a Windows Server 2008 R2 server running some web services through IIS 7. The web services run in integration mode with .NET Framework 2.0. The web services communicate with each other and with ...
1
vote
0answers
218 views

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 ...
1
vote
0answers
144 views

Apache serving Samba share leads to poor performance?

This is a question about a problematic interaction between Apache and Samba. Our Linux server (on a private intranet) mounts a Windows share, which is physically thousands of miles away, and serves ...
1
vote
1answer
927 views

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 ...
1
vote
0answers
37 views

Are memory and thread managers on Windows Server 2008 R2 and Windows 7 Home/Prof/Ultimate same?

I was asking one question on DBA site, and I got a reply, that implies, that Windows Server 2008 R2 and Windows 7 Home/Prof/Ultimate have different memory and thread managers. Is this correct?
1
vote
0answers
555 views

tomcat max number of threads

I have a very confusing scenario.. We are using tomcat6 to host an internal application. In server.xml file maxthreads attributes is set to 150 but if I log on to the manager, in "http-8080" section I ...
0
votes
5answers
4k views

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 ...
0
votes
1answer
755 views

List of PHP modules that are thread safe

I'd like to try running Apache in a threaded MPM with mod_php. Does anyone have a list of PHP modules that are thread safe so I can tell if its going to be safe to do or not?
0
votes
2answers
3k views

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 ...
0
votes
1answer
128 views

mongodb : Can create new thread on FreeBSD?

We experienced some strange thing in our mongodb gridfs platform. The platform actually is a bi Xeon E5 (bi quad core) with 128GB of memory, running on freebsd 9 with a zfs pool dedicated for mongodb. ...
0
votes
1answer
195 views

Tomcat maximum threads

I understand that setting the maximum number of connections available in a connection pool should be the same as your maxThreads configured for your Tomcat server (which correlates to the number of ...
0
votes
2answers
797 views

mysql thread count

We have a web application that uses apache and mysql. Generally (according to Munin) our MySQL thread count sits between 2 and 4 at all times. The other day, our server almost came to a halt. HTTP ...
0
votes
1answer
629 views

tomcat6 maxThreads property ignored

Hi in tomcat6 server.xml I have one connector for catalina service. And I set maxThreads=5: <Service name="Catalina"> <Connector port="8090" maxThreads="5" protocol="HTTP/1.1" ...
0
votes
1answer
2k views

Easiest way of upgrading pthread library in CentOS?

I am developing a deamon for my VPS. The program works perfectly in local (that has pthread-2.11.so) but in the vps (witch have pthread-2.5.so) it have a memory leak related to threads (each thread ...
0
votes
1answer
75 views

Starting program once leads to 10 instances

I have an old SUSE 8.1 server which just recently started acting crazy. If I start a program once: /usr/local/jdk1.6.0_21/bin/java -cp ...