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0
votes
0answers
6 views

Determining max concurrents on a LAMP stack, and related questions [duplicate]

Consider a basic LAMP stack with clients continuously long-polling it for anywhere from, say, five to 15 minutes at a time. (Note that the period of long-polls is around 30 seconds max; the five to 15 ...
0
votes
1answer
40 views

Server is not responding when single connection is blocked

I'm not sure how to properly specify this problem, I'm not really a server expert. I will be glad to provide additional data on demand. I have a PHP web-application running on Ubuntu Server with ...
0
votes
1answer
27 views

Excel 2013 Power Pivot RemoteApp - limited by 4 concurrent users? [closed]

We're trying to use Excel 2013 (64bit) + Power Pivot via RemoteApp. The problem we're having is basically the same as described this TechNet thread. 4 concurrent users have no problem using Power ...
0
votes
0answers
112 views

xmpp openfire connection manager not working

I have downloaded the connection manager here .In windows I have extracted it to program files in C drive and edit the conf/manager.xml to set domain and password. I also enabled connection manager in ...
2
votes
1answer
46 views

apache mpm_worker server failed to respond

I'm trying to update our current Apache 2.4.9 configuration from using prefork to worker mpm. I'm doing some simple load testing using jmeter to compare the performance between the 2. My first test is ...
0
votes
0answers
13 views

Static App, How Many concurrent connections can my basic vsp handle? [duplicate]

So I have this simple web app. What it does is simply outputting a xml file 1-3kb in size, gzipped. My current vps is a basic one, with 2 gb of ram and 2x2ghz processor power. I use centOS and nginx. ...
0
votes
1answer
91 views

Apache httpd response time increase with concurrent connections

I know many questions have been asked on this subject, but I didn't find an answer to help me. I'm trying to have Apache httpd answer 200 concurrent connections. I'm testing with jMeter, fetching a ...
0
votes
1answer
160 views

Ask nginx to handle requests from the same IP in parallel?

I have an application internal to my company that needs to be very fast per client, because the clients are so limited and the whole thing is internal. So, the client is expected to send so many ...
1
vote
1answer
66 views

Throttling a user across multiple datacenters

I'm trying to implement a throttling feature on nginx, that is shared across multiple servers across multiple datacenters. I would like to know what would be the best practice for building this. For ...
0
votes
1answer
435 views

Server's maxconn parameter in haproxy

I'm using HAProxy in production to balance queries to a series of server instances that can only process 1 query at a time (by our own decision). Knowing that I set the maxconn parameter in the server ...
2
votes
2answers
816 views

How to determine POSIX advisory file locks are working in simfs in the VM I'm using?

I'm looking for a command-line utility or some other way to test effectiveness of file locks, specifically POSIX advisory locks (which aren't only for POSIX, btw) in a Linux filesystem. Specifically, ...
0
votes
2answers
3k views

How does server handle multiple clients on the same port? Multiple sockets or multiple ports? [closed]

I have a misundertanding about some networking theory and because I couldn't find a definitive answer online (most resourceas are theory and theory etc without concise examples) I'm asking here. ...
2
votes
1answer
297 views

Plotted ab results of node, cluster and nginx, odd results?

I did a test with ab -n 10000 -c 1000 against node.js with different configurations, each returning the string Hello World!. Results seems odd to me. X axis is the number of requests, y is the ...
1
vote
0answers
138 views

Fail with ab test with nginx, two workers and 1024 connections?

I'm doing some tests with nginx 1.4.1 and Node.js 0.10.5 on my development machine (P8700 Dual Core 2.53Ghz, 4Gb RAM running Xubuntu x64). Unfortunately I can't do ab with 100000 requests with a ...
3
votes
2answers
188 views

How to lock concurrent access to a shared webservice from multiple webservers?

Our production environment consists in n Apache web servers accessed by browsers via a frontal load balancer. Very typical. 99% of our HTTP requests are gracefully handled by this parallelized ...
0
votes
1answer
260 views

iSCSI and NFS file locking and concurrency

I've got a linux host that need to mount a data share located on a NAS. The choice is between NFS v3 (NAS limitation) and iSCSI. The initial idea was to have a NFS mount to the file server that ...
0
votes
3answers
330 views

Several Cron at same minute

I'm installing a bunch of Magento shops on a webserver. Every website has a cron job that Magento uses to update its stuff -- it takes 3-4 seconds to complete. The instructions tell to set it to run ...
0
votes
1answer
4k views

Optimizing Apache for large concurrent requests and static files

OK, I know I'm asking a question that's been asked multiple times before (e.g. here - Serve millions of concurrent connections and static files?) but there appears to be no concrete solutions, so I ...
1
vote
3answers
78 views

What framework is good for delivering data that is commonly changed in a few second and is assessed by lots of people (similar to stock quote)? [closed]

I am only familiar with php and javascript and I guess php is not good at serving large amount of concurrent request. I would be grateful if someone can introduce me to more appropriate framework for ...
1
vote
2answers
897 views

Heavy write to Galera cluster - table locked, cluster practically unusable

I set up Galera Cluster on 3 nodes. It works perfectly for reading data. I have done simple application to make some test on the cluster. Unfortunately I have to say that the Cluster fails totally ...
3
votes
1answer
456 views

Apache Benchmark is slow from public network, magnitudes faster locally. What are some things I do to speed this up?

I am testing my Linode Ubuntu 14 64bit server out, it's the most basic server available from them. I am using Apache Benchmark to test the server, as well as a multithreaded script I wrote in Python, ...
0
votes
2answers
227 views

Simulating 1000 concurrent downloads

I'd like to simulate 1000 concurrent downloads of a single file from Cloudfront. I figured I'd setup ~10-20 xlarge EC2 instances for this. Is there an obvious way I'm missing to trigger this at the ...
3
votes
2answers
644 views

Tracking down “Connection reset” errors in Linux

I'm handling large numbers of concurrent downloads (approx. 500 per server) using Java. All the files are being downloaded from Amazon S3, and the downloading server is an EC2 m1.large instance. ...
10
votes
4answers
13k views

NGINX timeout after +200 concurrent connections

This is my nginx.conf (I've updated config to make sure that there is no PHP involved or any other bottlenecks): user nginx; worker_processes 4; worker_rlimit_nofile 10240; pid ...
0
votes
1answer
289 views

How do concurrent filesystems work? [closed]

From learning about how filesystems use transactions and logs to make sure that the disk is in an atomic state even after there's been a system crash, I've become curious about how filesystems deal ...
0
votes
1answer
191 views

How do i get concurrent asp.net on linux?

-edit2- It turns out asp.net (i dont know if its mono specific) blocks if the url and ip address are the same. Its nonblocking if i run it from my local machine and server at the same time. I have ...
2
votes
1answer
197 views

IIS 7.5 on Windows 7 Ultimate

I am looking to install Windows 7 Ultimate and run IIS 7.5 on it. However, I would like to know exactly what my limitations will be with this setup. While researching this topic various resources ...
1
vote
0answers
589 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
1answer
496 views

postfix concurrency limit with round robin dns

Take the following internal round robin dns setup mymta.com. IN A 172.31.1.1 mymta.com. IN A 172.31.1.2 mymta.com. IN A 172.31.1.3 mymta.com. IN A 172.31.1.4 mymta.com. IN A 172.31.1.5 mymta.com. IN ...
0
votes
1answer
261 views

Limit on concurrent connections: Determined by webserver or database?

Does the webserver or is it the database that limits the number of concurrent connections?
2
votes
5answers
753 views

Many concurrent SSH commands in a bash script?

My Bash-Foo is not strong. Right now I have something like function update_project { for i in server-{1,2,3,4} ; do echo "Updating $i" ssh $i "git pull" done } The number of servers is ...
3
votes
3answers
410 views

Super simple high performance http server

I´m building a url shortener web application and I would like to know the best architecture to do it in order to provide a fast and reliable service. I would like to have two separate servicies in ...
1
vote
1answer
521 views

proper concurrent users estimation case studies

I've been asked to size a web architecture for an excessive number of concurrent users ( hundreds of thousands ). I'm having a hard time convincing these people that unless you are in the top 5 of ...
0
votes
3answers
42 views

How two or more guest OS's hosted in a virtual environment handles editing of single resource?

I know this sounds very general question. Consider 2 OS's running using virtualization say operating system level virtualization. How concurrency is handled if both hosted OS using same resource and ...
0
votes
2answers
328 views

Where is the bottleneck?

There is a limit on connections somewhere along the line here... On a windows server 2008 machine, each request to a url running on localhost takes ~3 seconds to complete. This is fine and normal for ...
1
vote
3answers
223 views

Is NFS capable of preserving order of operations?

I have a diskless host 'A', that has a directory NFS mounted on server 'B'. A process on A writes to two files F1 and F2 in that directory, and a process on B monitors these files for changes. Assume ...