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

learn more… | top users | synonyms (2)

1
vote
1answer
72 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 ...
8
votes
2answers
152 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
vote
1answer
156 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 ...
1
vote
0answers
71 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 ...
0
votes
0answers
73 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 ...
1
vote
0answers
167 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 ...
0
votes
2answers
99 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
votes
1answer
120 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 ...
1
vote
2answers
77 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 ...
0
votes
1answer
47 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 ...
5
votes
2answers
499 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 ...
0
votes
0answers
45 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 ...
0
votes
0answers
66 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
votes
1answer
156 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 ...
1
vote
0answers
51 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
votes
1answer
171 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 ...
0
votes
0answers
118 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 ...
1
vote
0answers
98 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 ...
2
votes
2answers
99 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 ...
1
vote
1answer
45 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? ...
1
vote
1answer
481 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 ...
1
vote
2answers
149 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 ...
1
vote
1answer
54 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 ...
1
vote
1answer
104 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 ...
0
votes
1answer
97 views

Trading Engine running on RHEL 5.x [closed]

Before asking question quick background about myself working at one of trading company this is my 1st job as sysadmin I have finish my RHCE no experience how production server work. In our company ...
0
votes
0answers
55 views

Postfix smarthost with diffent relayhosts and sender dependant authentication

I've setup postfix as smarthost with different relayhosts and sender dependant authentication. Everything works ok, but I have a performance question. Is it better to send all the email corresponding ...
11
votes
1answer
420 views

Why do we get a sudden spike in response times?

We have an API that is implemented using ServiceStack which is hosted in IIS. While performing load testing of the API we discovered that the response times are good but that they deteriorate rapidly ...
0
votes
4answers
60 views

Limit copy speed

Unfortunately we have a pretty bad HDD performance on one of our servers and as soon as we start bigger copy process it stops to deliver any Apache response, which is really bad. Is there a way to ...
1
vote
2answers
42 views

How to limit disk performance?

I am load-testing a web application and studying the impact of some config tweaks (related to disk i/o) on the overall app performance, i.e. the amount of users that can be handled simultaneously. ...
2
votes
3answers
287 views

How to troubleshoot performance issues of PHP, MySQL and generic I/O

I have a WordPress based website running on a shared hosting. Its response time is very decent (around 2s to retrieve the HTML page and 5s to load all the resources). I was planning to move it to a ...
1
vote
0answers
92 views

Why does Process Explorer cause highly targeted failure of some applications / basic UI functions in a high-power EC2 Windows instance?

Update: I have determined that Process Explorer itself - the program I am using to debug a performance issue - seems to be the cause of the issue. See note, with updated question, at end. I am ...
2
votes
2answers
123 views

Sendmail slow to accept emails

I have a PHP web app which is using SMTP to sendmail on localhost to send email. I would like sendmail to accept the mail request immediately and queue it for later sending, as I don't want to have ...
0
votes
0answers
29 views

Infopath performance issue with RODC

We have number of infopath forms deployed across the organization. Recently we started experience unusual slowness in infopath forms opening on sites with RODC. Servers Win2008R2sp1, client Win7. ...
1
vote
0answers
19 views

Is it worthwhile, for performance reasons, to surround Apache mod_rewrite checks with Directives like Location, DirectoryMatch, etc?

I currently have a number of Apache rewrite rules using mod_rewrite (Apache 2.2). When I turn on rewrite logging I see a number of evaluations of rewrite conditions for files that have no chance of ...
0
votes
0answers
42 views

Boot disk with VMFS read/write driver

I want to rule out the ESXi kernel being the cause for my terrible 15MB/s write speed on the local VMFS datastore. I am using a Dell PERC H710 RAID controller, and would like to boot from a boot disk ...
2
votes
1answer
73 views

VMware Performance Monitor: How does aggregation work for VM Processor\% Processor Time

I'm monitoring a Windows Server 2008 R2 SP1 VM running on vSphere 5.1 for CPU bottlenecks. I'm using Performance Monitor and configured a few counters. Two of which are Processor\% Processor Time and ...
1
vote
3answers
195 views

Performance difference between compiled and binary linux distributions/packages

I was searching a lot on the internet and couldn't find an exact answer. There are distros like Gentoo (or FreeBSD) which does not come with binaries but only with source code for packages (ports). ...
1
vote
1answer
450 views

Slow Write Speed on ESXi host

I have an ESXi 5.0 free host with an internal datastore of 7.2K 5 disk RAID 5 using a PERC 710 mini RAID controller in a Dell Poweredge R620 Server with 32GB Ram and a 12 Core Xeon. I seem to get ...
2
votes
1answer
2k views

what is acceptable datastore latency on VMware ESXi host?

Looking at our performance figures on our existing VMware ESXi 4.1 host at the Datastore/Real-time performance data Write Latency Avg 14 ms Max 41 ms Read Latency Avg 4.5 ms Max 12 ms People ...
0
votes
3answers
146 views

Linux server became extremely slow

I have a file sharing website, and my files hosted in a server with those system specifications: 32GB RAM 12x3TB 2x Intel Quad Core E5620 I have files in this server up to 4gb for each file. 446gb ...
0
votes
0answers
83 views

How to find out which process is hogging the linux server?

We have a RHEL server. Today it suddenly became slow. Symptoms - It was responding slow to ping queries from other server. When I try to login using ssh, it was taking about 10 seconds to login. I was ...
3
votes
2answers
94 views

Can more memory than I need slow down my server?

We're about to install a memory intensive application and will purchase a server for it. The server will have at least 4 CPUs, with multiple cores. While the application is memory intensive, the ...
4
votes
4answers
313 views

Disk performance below expectations

this is a follow-up to a previous question that I asked (Two servers with inconsistent disk speed). I have a PowerEdge R510 server with a PERC H700 integrated RAID controller (call this Server B) ...
0
votes
1answer
812 views

Upgrading a PERC h310 to a PERC H710 mini RAID controller on a Dell R620

I have an ESXi 5.0 Free license host using an internal Datastore (RAID 5, 5 Disk) that was configured with a Dell PERC h310 RAID controller. The disk performance was very poor, so I upgraded to the ...
2
votes
0answers
50 views

IBM xSeries 306 CPU Speed

I have an IBM xSeries 306. The system has been flawless until a week ago. It's a Pentium 4 Dual Core CPU. The CPU speed is 3.20 gHz. Now, it shows 4.26 gHz or 2.16 gHz when the POST screen comes ...
1
vote
0answers
22 views

Difference between all servers in one cluster and more than one cluster with servers? [closed]

Not sure I understand what´s the difference or how it works when servers a running in one cluster or if there are more than one clusters with servers in it - regard High availability & Load ...
2
votes
1answer
302 views

Large keepalive_requests values are severely slowing-down Nginx

When running a bacon (43-byte transparent pixel) load test on Nginx, we have tried several keepalive_requests values (from 10 to 100,000) and the optimal value seems to be 10. Here are the server ...
1
vote
1answer
178 views

How to erase a SSD to restore factory performance in Linux?

Due to big performance issues with an mdraid-1 array I'd like to pull down from the array one of the devices (Samsung 840 Pro), erase it to restore factory performance and re-add it to the array. The ...
0
votes
0answers
164 views

Configuring ubuntu web server for wordpress stress test with apache jmeter

sorry for my english and the wall of text in advance. I've been given a project where I have to setup and configure a server with wordpress in a local environment, for stress/load testing purposes. ...
1
vote
0answers
81 views

big speed difference on a network link with and without VPN tunnel

Scenario: We have a network link between two offices. The link is provided by a third party company through a VLAN on their network, but to us it is totally transparent -as if we had a simple ...