Questions about server hardware and software performance, or network performance.

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How do I reduce server load for a dormant WordPress site using W3 Total Cache?

My current host who did all performance optimization for me has jacked up their price to $1,000/month, so I was forced to move to a new host. The new host charges only $150/month. They give you W3 ...
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0answers
34 views

How to benchmark a whole storage infrastructure

I'm a 100% sure that I'm not the first one to consider benchmarking a whole infrastructure, but yet I haven't found any relevant information on how to face this challenge. As I guess we all know what ...
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1answer
423 views

HTTPS overhead compared to HTTP

HTTPS is the encrypted version of HTTP, and nowadays it is becoming a common practice to encrypt all the web traffic, not only sensitive one. The drawback of HTTPS, apart from the need to buy ...
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1answer
38 views

Wireless performance, normal results

Here is the setup: An IBM server machine connected to a TP-Link TL-WR1043ND (latest firmware). It is connected with a wired gigabit connection. An lenovo laptop with a centrino wireless-n 2230 and a ...
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2answers
39 views

What exactly is controlling single HTTP requests speed? [closed]

As you may know using multiple HTTP threads when downloading a file from a server can significantly increase your download speeds if not max it out. What is control of determine the throughput of ...
2
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1answer
130 views

My Ubuntu VPS is not using available swap, even if OOM. What to do?

I recently added 1 GB of swap to my Ubuntu virtual private server to prevent MySQL crashes on RAM overloading. I followed this tutorial. I use htop to monitor resources. When I use loadimpact to test ...
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4answers
857 views

LSI RAID: Write cache policy affects read performance?

I have a server with a LSI MegaRAID SAS 9260-4i controller, RAID-5 with 3 x 2 TB disks. I did some performance testing (with iozone3) and the numbers show clearly that the write cache policy affects ...
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1answer
48 views

Advice on web server performance troubleshooting is needed

I'm renting a virtual CentOS based server where I have about 5 active sites running. Several months ago I noticed a significant performance degradation in how my sites are running. First symptom was ...
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2answers
103 views

How to tell which script is slowing down the server the most?

As it happens often to coders, I had to take over someone else's code for this company, the server runs on Amazon Cloud (i2.xlarge) running ubuntu-saucy-13.10-amd64-server. (the guy left) The ...
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2answers
206 views

Why does dd show slow disk speed first time?

I'm checking the disk speed of a hdd on CentOS 6 using dd command. The setup is a DRBD setup - with this server being primary. To ensure that I get correct values, I execute the dd command 3 times ...
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2answers
839 views

Poor SQL performance on HP ProLiant ML310e Gen8 v2 with raid10

I recently bought HP ProLiant ML310e Gen8 v2 server with 8G's RAM and 4 HP 1TB 6G 7.2k rpm SATA (3.5in) Non-Hot Plug MDL HDD disks. It was surprise to me that HP didn't provide debian drivers for ...
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2answers
394 views

Importance of disk alignment for Windows Server 2012

I saw article about Disk alignment here and also here.Also there where some references that windows server 2003 has some problem with disk alignment. After reading article I am confused whether we ...
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0answers
139 views

Why are pgpgin/s and majflt/s inconsistent in sar -B?

In sar -B ouptut, I would naively expect pgpgin/s to equal majflt/s multiplied by the system page size. From man sar: pgpgin/s Total number of kilobytes the system paged in ...
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1answer
40 views

Firewall Connections fail to open under load

Problem : During High load , our applications are encountering errors : java.net.connection Time out. After some investigation , we found out that it was Firewall the root cause, but still don't know ...
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1answer
29 views

Slow application performance in one location

We have a problem that perplexing both of us in our department. We have a video viewing application that we need to have loaded on a workstation to be used in a particular location. When we load a ...
0
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1answer
106 views

Using all host resources for a single Windows VM (KVM) - how to improve performance

We're using KVM/qemu on Ubuntu 12.04 to spawn a Windows 2008 R2 VM that uses a lot of host resources (all CPU cores, 4GB RAM). It seems that during a Windows boot that Windows allocates all its ...
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1answer
84 views

How Long Should Data Collection Sets run in Windows Server Performance Montioring

I currently have an application server and a database server both running on Windows Server 2008 R2. I have been tasked with generating a weekly report on the utilization of CPU, Memory and Disk. I am ...
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1answer
45 views

uk vps server route to thailand? [closed]

I'm just a Javascript developer using node.js... My host has got me a vps sever in england. I have had someone test my site loading in england and it is lightning fast. I've also had someone test in ...
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1answer
260 views

High CPU load caused by slow disks?

We are running a online application on a 3-year old server (quadcore Xeon, 4GB RAM, SAN-disks). The server hosts besides the web application a SQL-, FTP-, SFTP, SMTP, and POP-services. Over the years ...
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1answer
98 views

Performance impact of slower encryption/hash/group settings in Phase 1

When defining IPSec VPN tunnels, how much of a performance impact can I expect from choosing "stronger" Phase 1 settings (such as AES256/SHA1/DH5 over DES/MD5/DH1)? For example, I'm told that AES-256 ...
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1answer
39 views

Loss of performance on backup power

I tested my system on backup and saw considerable degradation in performance when running on backup. Here are the results: Config: CPU: 2.0 Ghz, 6 Core, 12 Threads RAM: 16 GB UPS: 600W/ 1000VA PSU: ...
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3answers
219 views

Does software RAID-0 really improve performance?

I am going to lease a server and I have two options, SATA or SSD, I decided to save the money and go for the SATA option. But I do not need all that storage they are giving me! So I thought MAYBE I ...
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0answers
126 views

mdadm raid10 or nfs performance issues?

I have a fresh mdadm RAID10 device which is healthy, built from 4 x 7200rpm SATA 3 drives: # cat /proc/mdstat Personalities : [raid10] [raid1] md2 : active raid10 sdc3[5] sda3[4] sdb3[1] sdd3[3] ...
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0answers
80 views

Infiniband link is at 4X SDR with DDR HCAs; has anyone seen this before?

I've recently upgraded my Infiniband HCAs from SDR to DDR, however upon upgrading, it has not improved the link speed at all. Receiving the following output from 'iblinkinfo': CA: ip-san-1-au3a ...
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1answer
91 views

Website is slow without https

As you can see, http://coinad.com/ is slow, and https://coinad.com/ is fast. I've upgraded the server, reviewed the code, optimized the tables and anything seems to work. This is driving me mentally ...
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1answer
228 views

iSCSI TGTD over InfiniBand Performance

I have just configured a server-to-server 4x SDR InfiniBand link to increase bandwidth for the backend storage of my virtual machines, specifically a database server. I am using iSCSI with TGTD on ...
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1answer
95 views

Choosing the right database/storage engine for iptables ulogd

I'm looking for some help choosing a database backend for a iptables ulogd setup. We are going to swap out our current proprietary firewall solution with iptables and one of the requirements is to ...
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3answers
243 views

Adding CPUs puts MySQL 5.5 (Debian) performance down

I am about to setup a database server (MySQL) in OpenVZ container and I've been wondering how many CPUs I should assign to it. I decided to benchmark it. I compared two OS/MySQL distributions and ...
1
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1answer
323 views

3ware card in RAID-5 configuration slow and causes load when writing

I have a 1Gb/s bandwidth between my computers. The source can actually read and send data at 25MB/s via SSH. My test file is 4GB, I use scp without compression for the test transfer. The rate is ...
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0answers
148 views

Apache AB results: why does adding concurrency not increase requests processed per second?

So I've been trying to use apache ab to benchmark performance, but I'm having trouble understanding why I'm getting these results. FYI, its a PHP app using Zend Framework, mySQL database, and mostly ...
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0answers
110 views

Subversion performance issue on Linux

My developers is complaining our SVN is slow. This is the data they collected:http://i.stack.imgur.com/SmYUS.jpg. The SVN server is on Linux in Canada and developers using Cygwin on Windows in UK. So ...
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0answers
297 views

windows2012 failover cluster + storage. Considerations

We plan to build a failover storage with Windows2012r2. There will be 2 or 3 physical machines with 2 virtual machines on each server. One virtual machine building a failover, second one being storage ...
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2answers
160 views

FS for many small files, mostly reads?

I need a direction since all the blogs/benchs seems to contradict. Goal: Having a lot of small files on FS in a directory tree fashion similar to this AB/CD/EF... Two size groups : G1 : 10-20 kB G2 ...
3
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1answer
165 views

IO related performance bottleneck on a LAMP server

I am administering a big LAMP server with some thousand users. About a week ago, things slowed down, and the only thing I see that the IO latency is increased dramatically. Users experience slow page ...
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2answers
103 views

Different name servers for different countries. Speed up DNS lookup time [duplicate]

Is it possible to create different NS for different countries? For example, we have 4 nameservers: #for US ns1.us.domain.com ns2.us.domain.com #for Europe ns1.europa.domain.com ...
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1answer
63 views

Order that Apache handles .htaccess directives

I was working on a WordPress site yesterday, mostly in a Web Performance Optimization capacity (on shared hosting). At one point I noticed that my .htaccess file had redundant, possibly ...
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2answers
1k views

Relation between disk IOPS and sar tps

I'm trying to estimate IOPS requirements of my application running on 32-bit CentOS 6.2. I started to take some measurement on a machine with SATA disks and I'm quite confused of difference between ...
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0answers
57 views

Windows servers on same gigabit lan switch, what might cause Windows 2008 R2 to have 50% longer ping times than Windows 2003 server?

After installing a brand new HP Proliant DL380e Gen8 running SBS 2011 (Windows 2008 R2 X64) I noticed a difference in response to ping requests on the wired ethernet local LAN, even before the ...
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0answers
124 views

Server wait time increases to over 5 seconds

http://i.stack.imgur.com/pxqRp.png As you can see in the above pingdom report screenshot, the wait time for this website http://quotepix.com and all other websites on the server have shot up to ...
2
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1answer
372 views

CentOS Tuned Equivalent For Debian

Running a few systems, a few are Debian which have been great. I have on the CentOS boxes tuned(tuned-adm) installed and setup for throughput. I searched all over Google and only found some articles ...
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0answers
136 views

Reason for high CPU time when executing fio

After weeks of troubleshooting some performance issues I have on my VPS running Ubuntu 12.04 LTS, I am getting closer to the conclusion that the problem is related to IO. When I have a considerable ...
0
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1answer
490 views

MySQL Performance Bottleneck - I/O or CPU?

I'm developing a web app and have run into a large performance difference between the speed of MySQL lookups on my development and live environments. DATABASE: 2.5GB, three tables (one table has ...
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0answers
258 views

Server & Mysql Config for Magento

I will appreciate if someone can help us as we think our server admin has no clue. We are having issues with our server such as mysql using too much CPU sometimes up to 70%. Especially when security ...
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0answers
119 views

best setup for fast sustained streaming (sequential?) disk writes

i am setting up a high speed/high resolution scientific image acquisition system. i need data write rates of ~1 GB/sec sustained for ~1 hour. i don't have experience with raid, but my plan is to ...
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2answers
152 views

ipfw based firewall slows down Apache web server

I have an Apache web server running on a FreeBSD 8.3 machine. That machine has an ipfw firewall with these rules: root@aigamedev:~# ipfw -a list 00005 0 0 deny ip from 67.212.xxx.xxx to any ...
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1answer
60 views

Traffic monitoring tools for IIS server?

We are planning to optimize IIS server.We are doing load testing of 20 concurrent user and want to see the bottleneck. How to monitor each request/response times? and check where is the bottleneck? ...
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2answers
766 views

How to delete unknown user profiles remotely?

When user is deleted from Active Directory, it shows as an unknown user. System properties -> Advanced -> User Profile -> Settings... I have to delete it manually all the time. There are more than ...
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2answers
526 views

Windows Server 2008: “not genuine” - performance impact?

Is it possible that not activating a copy of Windows Server 2008 might have a performance impact, specifically over TCP? Background: I've been provided with a Windows Server 2008 Oracle VM. It ...
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1answer
94 views

How to benchmark SSL performance IIS

We are moving from Windows 2003 IIS 6 to Windows 2012 IIS 8. When moving over to the 2012 we have seen a slow down of the website of at least 10 times and sometimes more under load. Initial testing ...
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1answer
105 views

Why are we having problems with multiple nics in office and production networks going to 100mbps mode?

updates and additional info 2 environments, office and production at datacenter Both environments have Cat-5e cables, a cable was replaced when it tested as bad with Broadcom's cable testing, and ...