A bottleneck is the place where transmission is the slowest.

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0answers
113 views

Finding if the current open processes reaches FcgidMaxProcesses ? (bottleneck)

To make it short : I fail to find if I'm not hitting the FcgidMaxProcesses limit as a bottleneck. Longer version following I have a server Debian Wheezy, two Raid-1 SSDs for system and two ...
2
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1answer
2k views

MySQL high CPU usage on small website

I have a small website hosted on a dedicated server (FreeBSD 9.2, MySQL 5.6.1 and php 5.5.5). The problem is that MySQL eats a lot of cpu resources even if the website have a few visitors. The ...
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1answer
3k views

How to troubleshoot slow performance on AWS EC2/RDS?

We recently moved our web servers from some 10 year old boxes to AWS EC2. Usage of the site is currently higher now (it's our busy season) and the site has become much slower, which is unexpected ...
2
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2answers
50 views

Estimate if the network throughput is reached

I have 2 processes communicating over TCP/IP as following: process A sends 20 KB of data to process B and after some calculations process B sends the response (2KB) back to A. When I run both ...
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4answers
119 views

Does using all cores reduce efficiency?

I have a program (well, php script) which does some pretty heavy text searching - it loads a 2mb and 40mb file and searches through them to find where each word that appears in the first is present in ...
0
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1answer
108 views

Network card capable of capturing a tonne of packets and not dropping them?

Edit: Our server is trying to capture packets at between 500-600Mb/s, but is dropping packets 'due to kernel'. Data is being written to SSDs, and isn't bottleneck there. What things should I look ...
0
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1answer
162 views

How can I find the bottle neck? [duplicate]

I have a EC2 m1.large Ubuntu 13.04 Instance runs PHP 5.5, PHP-FPM and NGINX. Cache is handled by Elastic Cache using Redis and the database connects to a separate m1.large MongoDB server. The content ...
6
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2answers
607 views

Why is Postgres sitting 95% idle, with no file I/O?

I have a TileMill/PostGIS stack running on an 8 core Ubuntu 12.04 VM on an OpenStack cloud. It's a rebuild of a very similar system which was running nicely on very similar hardware (same cloud, but ...
2
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1answer
62 views

May a low DRAM router be a bottleneck for a LAN?

I need to install a LAN that is a hybrid between a star LAN and a cascade LAN. There are two levels (I mean that the maximum number of link to go from the central switch to the most external switch is ...
2
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4answers
5k views

Flush-0:n processes causing massive bottleneck

I have a LAMP cluster that shares files via NFS and occasionally one of them will be stricken for a while when mysterious flush processes start appearing. Can anyone help me? The only way to resolve ...
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6answers
995 views

Linux I/O bottleneck with data-movers

I have a 24 core machine with 94.6GiB RAM running Ubuntu server 10.04. The box is experiencing high %iowait, unlike another server we have (4 cores) running the same types and amounts of processes. ...
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1answer
179 views

Server hard disk read speed and client download speed, is there a connection? [closed]

Ok so a client's download speed is only as fast as a server's upload speed, and vice versa. Based on the answers to this post: Does upload speed depend upon download speed of the server? In other ...
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0answers
108 views

Good Perfmon Counters for Initial Troubleshooting

I increasingly deal with users who complain there "computer is slow" or that "it takes forever to load" on the laptops we provide (fairly standard build of Windows 7 32-bit with Office 2010 and a few ...
2
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5answers
2k views

Performance monitoring on Linux/Unix

I run a few Windows servers and (Debian and Ubuntu) Linux and AIX servers. I would like to continously monitor performance on these systems in order to easily identify bottlenecks as well as to have ...
2
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1answer
351 views

Solaris/UNIX: Does snoop have the potential to slow down network traffic?

This is the way I see it. A copy of the network activity is written to a buffer, and snoop reads from the buffer. As long as snoop is able to get the data out fast enough (writing directly to a file ...
1
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1answer
191 views

Server freeze (Disk I/O possibly)

I have a Windows Server 2008 machine that is resyncing disks after a powerloss. The issue is that the system becomes unresponsive after about 10 minutes. We've checked with resource monitor and found ...
1
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1answer
1k views

Mysql hangs up the server. How to avoid this?

Sometimes my website 'goes down' due to Mysql consuming all the resources, but I think it does not stop creating more httpd processes. Is that possible? If I restart apache, these processes disappear ...
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2answers
3k views

What iowait values are ok?

I am trying to find the bottleneck of a server running a fairly busy php/mysql site. My first culprit was io but iostat shows that on average iowait consumes only %3.60 of cpu time. here is the ...
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1answer
1k views

Diagnosing the slow performance of my NAS?

I recently built a NAS box on top of ubuntu server. I have an average transfer of about 10mb/sec over gigabit wire to my computer. I was hoping you guys could give recommendations on how to pinpoint ...
2
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2answers
110 views

web app reaching emailing limits - what is the next step up?

Recently i have been working on a popular web app that currently has around 70k members and a lot of traffic, i migrated the site to a new extra large EC2 instance and it seems to be a massive ...
1
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2answers
945 views

Should I use nginx exclusively, or have it as a proxy to Tomcat (performance related)?

I've planned to create a website that'll be pretty heavy on dynamic content, and want to know what would be the wisest choice for part of my webstack. Right now I'm trying to decide whether I should ...
2
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1answer
776 views

Tangible benefits of keeping web applications and web server separate?

We develop and maintain web applications; and in our current setup; we are using a three-tier system of database server, application server, and web server. So far, so good. The problem we are ...
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3answers
366 views

Where to look for the bottleneck when download slows down?

Image downloading from our site slows down every evening. Compared to daytime we get %50 more traffic over the evening. In exact figures, during daytime hours, hourly pageview count is around 20k, ...
4
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2answers
2k views

Steps to diagnose performance bottlenecks on Mac OS X

If you wanted to track down performance issues on a machine running Mac OS X and find out what was causing slowdowns, which command-line or graphical tools would you use, and how would you use them? ...
3
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3answers
883 views

How to determine bottlenecks on Ubuntu LAMP environment

What kind of tests should I run to determine bottlenecks on my server? I'm trying to optimize so I can maintain heavy load spikes when they occur. I'm running Ubuntu in a LAMP environment.
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1answer
537 views

Significant advantages to choosing nginx+PHP-FPM over Apache+mod_php for a Dynamic DB-backed PHP api server?

I am considering using Nginx once again as the primary web server for a REST web-API we need to deploy very quickly(nginx initially chosen for its C10k properties.) The initial implementation of the ...
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3answers
312 views

Identifying the bottleneck

So I've got nginx and php-fpm on a cloud server. Using apache benchmark with these settings: ab -n 300 -c 5 http://example.com/ So the cloud server (from rackspace) was a 256mb one. I ran htop while ...
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1answer
312 views

How to Build a High Performance Network Traffic Recorder With no Bottlenecks (20Gbps)

I need to build a server which is capable of capturing 20 Gigabit/second network traffic (2 x 10g network adapters - 99% utilization) and store them on a disk with zero packet-lose. The requirements ...
0
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1answer
677 views

Looking for a bottleneck in MySQL server

I have two Ubuntu servers with very similar, if not identical, configuration: both have 16 cores (4 E5540 Xeons), 16GB RAM, HP Smart Array P212 controllers with 2 HDDs in RAID1. I/O scheduler used is ...
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2answers
138 views

Hypervisor load on local disks

What is the I/O load on the local disk system for the host OS in XenServer? I can't find this info anywhere. As we have a SAN for the VMs themselves, can we get away with cheap controller / SATA disk ...
1
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3answers
856 views

Very slow harddisk performance

Today I was trying to execute a long-running (but highly optimized) query on a server in our company. I've run the same query on the same data on my home computer (5400rpm harddisk) and it took about ...
1
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1answer
2k views

Bandwidth bottleneck on VMWare ESX Virtual Machine

I have 2 loadbalanced apache virtual servers that handle a couple thousand requests per minute, and I am trying to diagnose the bottleneck that is slowing them down. My webservers each have one ...
2
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4answers
6k views

How to find the bottleneck while transferring huge files between 2 hosts

We frequently need to transfer huge files (upwards of 50 GB) between two hosts, and the transfer rate never seems to reach the expected throughput for the network. There are several points which could ...
0
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2answers
126 views

mySQL Database Performing Extremely Poor on INSERT, DESTROY, but fine on FIND and UPDATE

I believe I've encountered a database scaling issue. I have a table with nearly a million rows in it now and our rails application appears to be hanging whenever we try to create a new instance. I ...
1
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2answers
748 views

How to tell whats making this server slow

Hello I have an HP server configured for RAID 1+0 using 2 SATA disks. I'm pretty new to handling servers also. The server has had the same OS(Windows Server 2003) on it for a while so I'm not sure ...
2
votes
1answer
783 views

Disk or Network Bottleneck and Perfmon?

I'm trying to see if we're choking our NAS server with RAID 5 on a PERC RAID card. I've been playing with Perfmon and have been looking at various ways to try narrowing down the performance counting ...
3
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4answers
779 views

Recommended SSD Setup

I'm building a new server which will be running a text search service for our online web services. This service requires fast IO so I am trying to further reduce any potential bottlenecks. I would ...
0
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2answers
234 views

How do I know when server “runs at speed limit”?

Basically I'd like to know if it's possible to speed up my server or not by using caching like squid, checking for possible errors in configuration, optimizing various server software parameters, etc. ...
6
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6answers
7k views

Find the bottleneck: disk I/O on Windows XP

One of our development boxes has developed a problem wherein performance will occasionally drop through the floor. When this happens, you can hear the hard drive thrashing, but I don't know what's ...