Optimization is the process of modifying a system to make some aspect of it work more efficiently or use fewer resources.

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26
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5answers
3k views

What configuration options for MySQL provide the biggest speed improvements?

What configuration options for MySQL provide the biggest speed improvements? I'm wondering about actual configuration file improvements, table types, hardware setups, replication, etc. Anything other ...
25
votes
8answers
18k views

Why rsync is faster than NFS?

Few days ago I noticed something rather odd (at least for me). I ran rsync copying the same data and deleting it afterwards to NFS mount, called /nfs_mount/TEST. This /nfs_mount/TEST is ...
23
votes
7answers
5k views

Options to efficiently synchronize 1 million files with remote servers?

At a company I work for we have such a thing called "playlists" which are small files ~100-300 bytes each. There's about a million of them. About 100,000 of them get changed every hour. These ...
19
votes
3answers
42k views

Optimal values for ServerLimit, MaxClients, MaxRequestsPerChild directives

I'm running a traffic intense site plenty of dynamic content, mostly user-generated. The server is a dedicated one and has a total of 4 Intel(R) Xeon(R) CPU X3210 @ 2.13GHz proccesors. I need to know ...
17
votes
6answers
13k views

Optimize apache/php/mysql running on VPS for heavy load

Question about optimizing an apache/mysql server on a VPS with 512m of RAM. Under normal load everything runs fast, no connection lag. However when we get our heavy traffic days (50k+ visits) the ...
17
votes
2answers
8k views

IIS 7.5 optimizations for a site serving only static content

I'm looking to setup a cookie-free domain intended to serve static content for a web application, similar to the http://sstatic.net/ site that the stack exchange sites use. My question is, what ...
14
votes
6answers
501 views

First days online : how not to kill your site

Suppose you have this fancy new site, with lots of data (like big images), and you're about to put it online. If you do "too much" publicity, during the first days, the site will be overwhelmed with ...
14
votes
2answers
11k views

How to determine the best byte size for the dd command

I know that doing a dd if=/dev/hda of=/dev/hdb does a deep hard drive copy. I've heard that people have been able to speed up the process by increasing the number of bytes that are read and written at ...
13
votes
3answers
3k views

Building a 1,000M row MySQL table

This question is reposted from Stack Overflow based on a suggestion in the comments, apologies for the duplication. Questions Question 1: as the size of the database table gets larger how can I tune ...
10
votes
5answers
7k views

How to minimise SpamAssassin (spamd) memory use

I'm using SpamAssassin on Debian (the default configuration with Pyzor, AWL and Bayes disabled, and sa-compile enabled), and each of the spamd child processes consume around 100 to 150MB of memory ...
9
votes
1answer
920 views

How can I tell when it is time to defrag my SQLServer database?

What is the best practice for measuring SQLServer database fragmentation/performance rolloff and determining when to defrag a SQLServer database table? I'm most interested in learning what the useful ...
9
votes
2answers
2k views

Linux Slow Start: Changing ip route does not have any effect on initial window

I changed the tcp initial window in my machine to 10 as shown below [user@site etc]$ sudo ip route change default via 17.255.209.1 dev eth0 proto static initcwnd 10 And changed ...
8
votes
4answers
1k views

IIS Optimization

What kind of optimization (performance or whatever) do you use when going live with IIS (on windows 2003) ? Currently, I use 1 application pool per web site, but I think I can do more :)
7
votes
1answer
1k views

When should you use and not use Etags?

I was just looking at our site on WebPageTest.org and one of their recommendations for speeding up a website is: ETag headers should generally not be used unless you have an explicit reason to ...
7
votes
3answers
2k views

Maximizing rsync performance and throughput - directly-connected gigabit servers

I have two Dell R515 servers running CentOS 6.5, with one of the broadcom NICs in each directly attached to the other. I use the direct link to push backups from the main server in the pair to the ...
7
votes
1answer
3k views

How to select the best Stripe Size when configuring a RAID Array

There are various "references" on the Internet that delve into some discussion about what factors to consider when selecting a particular RAID stripe size (4KB to 128KB or more) for an array of disks, ...
6
votes
2answers
463 views

Do you remove unwanted packages (*NIX), or do you disable them?

Im currently building a cobbler and puppet setup. One thing I do is disabling unwanted services with puppet, but then I thought: Should I remove them with cobbler, rather than disabling them after ...
6
votes
3answers
4k views

Guest optimization tips for Ubuntu on VirtualBox [closed]

I was wondering if anyone could shed light into "Guest optimization tips for Ubuntu (guest)" I came across http://serverfault.com/questions/18290/virtual-machine-guest-optimization-tips, for Windows. ...
6
votes
6answers
7k views

How many files in a directory is too many? (Downloading data from net)

Greetings, I'm writing some scripts to process images from various photo websites. Right now I'm storing all this data in individual text files in the same directory. The directory is web ...
6
votes
3answers
4k views

Can I optimize these APC settings more?

I would like to optimize APC some more but I am not sure where I could do something. First here is the screenshot after one week of running with the current configuration: I have now the following ...
6
votes
2answers
5k views

Fixing window scaling problems with Linux TCP

I'm trying to improve the throughput of one of my servers overseas and after monitoring a transfer between the server and my home computer with wireshark I'm pretty sure I have a problem with the ...
5
votes
4answers
191 views

Is it good or not to include all frequently used and important addresses in /etc/hosts?

Is it generally considered a good or bad practice to include all frequently used and company's important hosts in /etc/hosts? Now I can see the following pros and cons: Pros: improved speed, ...
5
votes
4answers
5k views

Profiling Apache+Mysql+Php server - which is the bottleneck?

How do I profile an Linux + Apache + Mysql + Php server for speed? I have a server with a heavily modified MediaWiki instance running on Ubuntu 8.04. It's a bit sluggish - I haven't done anything to ...
5
votes
6answers
567 views

Capacity Optimization / Deduplication Options for Primary Storage

I'm exploring options for making more efficient use of our primary storage. Our current NAS is an HP ProLiant DL380 G5 with an HP Storageworks MSA20, and one other disk shelf which I'm not sure what ...
5
votes
2answers
571 views

How can I handle big traffic spikes on my dedicated server?

I have an E-Commerce site, which gains a sudden peak of very high traffic when I turn on different ads campaigns. From this moment on, my current dedicated server (Hostgator, 4GB Memoray, 100mbps ...
5
votes
3answers
1k views

Optimizing VPS Server Memory

WHAT I'M TRYING TO DO The server resource limits sometimes run tight; to help prevent memory exhaustion, I've had to limit server processes. I'm needing a little expert help to know if I'm on the ...
5
votes
2answers
1k views

How do I optimize TCP stack for HTTP server?

I have a HTTP server that serves only two kinds of page: about 10 KB and about 16 KB (both compressed, other files are from CDN). As the latency is quite high (ping takes more than 300 ms), I want to ...
5
votes
1answer
3k views

Nginx auto minify html output

does anyone know of a way to get nginx (or any other method) to minify html output on the fly? It seems straightforward to me and can shave a few kb off and help speed up the site.
5
votes
2answers
3k views

Optimizing MySQL for small VPS

I'm trying to optimize my MySQL config for a verrry small VPS. The VPS is also running NGINX/PHP-FPM and Magento; all with a limit of 250MB of RAM. This is an output of MySQL Tuner... -------- ...
4
votes
8answers
4k views

Optimize a fresh Ubuntu server installation

After installing a fresh Ubuntu server (I personally use 8.04 LTS) what do you do to optimize it in terms of memory consumption, disk usage and speed? What services and pre-installed packages do you ...
4
votes
3answers
2k views

Way to configure apache for ~125 django sites to optimize memory usage (mod_python v mod_wsgi; worker vs prefork; static files)

I'm currently running 125 Django sites on a single dedicated box at GoDaddy. The sites are relativelly low traffic and I'm wondering what i can do to optimize the memory usage in my apache config. ...
4
votes
2answers
1k views

Disk I/O utilization up to 100% after tuning InnoDB-related MySQL configuration

I have added following lines to "my.conf": query_cache_size=128M innodb_buffer_pool_size=512M innodb_flush_method=O_DIRECT After that Disk utilization started raising, reached 100% and holds ...
4
votes
2answers
345 views

Cron job for database repair and optimization

I would like to repair + optimize my MySQL database once a week! How could I do this?
4
votes
2answers
4k views

What are typical NFS read/write rates

I have just installed a server that is sending HTTP video streaming files to a Web server over NFS and I want to make sure that I have the transfer speed optimized. But I don't know what sort of ...
4
votes
3answers
189 views

run local MySQL instance for fast mysql_real_escape_string calls

Currently all MySQL data/API calls are handled by a remote DB cluster (i.e. network latency is a factor in total script execution time). To reduce execution time in this context, would it be sensible ...
4
votes
2answers
2k views

Performance problems when running Java desktop applications on Citrix Metaframe

We have a desktop Java application running within a Citrix Metaframe server farm and the performance, specially while starting up the app, is very unreliable. Sometimes it takes 15 seconds and ...
4
votes
0answers
170 views

What does it mean when Twitter says their entire database is in RAM?

I am wondering where to begin with database scaling/optimization strategies. After reading articles like highscalability.com's facebook architecture article, and this twitter architecture article, I ...
3
votes
6answers
2k views

Method for finding unnecessary indexes of an operational SQL Server database?

Besides wasting space on the database, unnecessary indexes on SQL Server can slow down insert and update operations. Developers who lack experience in database principles sometimes tend to create ...
3
votes
3answers
250 views

How exactly does virtualization help reduce IT infrastructure cost? [closed]

I keep hearing a lot about virtualization and a lot of claims that it helps reduce IT infrastructure costs. How exactly is the latter achieved? Is the benefit coming from running several virtual ...
3
votes
8answers
2k views

Scaling a LAMP stack

Once you move beyond 100k hits/month, what would people in this community say is the biggest hurdle? My situ: Tons of static media (audio/video/images) being served off of S3/CDN, but being stored ...
3
votes
5answers
7k views

How to Best Manage High PostgreSQL CPU Use?

I am trying to fix a high PostgreSQL CPU use problem. We are using PostgreSQL 8.0.9 and when our JEE web application (in JBoss) is used in certain load increase conditions, top shows a slow increase ...
3
votes
2answers
840 views

Do access logs (from nginx) slow down a website?

Does it slow down a website if your webserver (in my case, nginx) is writing to an access log? I'm mostly wondering if it's noticeable. Plus, what's the point of knowing the user agents / ips that ...
3
votes
6answers
1k views

MySQL performance tuning

I'm looking for a succinct list of common pitfalls and optimizations for tuning a MySQL server as used for mid-size websites. In general, the type of advice I'm looking for here is information that ...
3
votes
4answers
7k views

Windows file server performance tuning

I seek your opinion and tips/suggestions in optimizing the performance of a new Windows file server I'm building. I've inherited a Dell NF500 storage server (basically Dell 2950 with Windows 2k3 ...
3
votes
4answers
867 views

Optimizing apache server load

We have an issue with a dedicated server load. We have 16 processors with 4 core @ 2.40GHz, if I understood correctly cat /proc/cpuinfo output. Unfortunately, I don't have access to free -m or ...
3
votes
2answers
134 views

Snow Leopard: Optimization

I have bunch of questions: I have a Mac network, which has five Mac's. Right now, they are individually getting software updates. Is there a way to download the patches/security updates in a single ...
3
votes
3answers
2k views

Have I pushed the limits of my current VPS or is there room for optimization?

I am currently on a mediatemple DV server (basic) 512mb dedicated ram, this is a CentOS based VPS with Plesk and Virtuozzo. My experience with it from day 1 has been bad and I only could sooth my ...
3
votes
2answers
2k views

PHP + Apache long wait time

I've run into a bit of a brick wall with troubleshooting my dedicated websever. Recently, my website spiked with the amount of request/per second and it crashed. The box original had 8GB of RAM, 8 ...
3
votes
2answers
1k views

How can I determine the memory used by a forked process (Linux)?

Following on from this question. Debian, if that matters. I understand that some memory is shared between forked processes. How then can I determine how much memory is used by a process/set of ...
3
votes
1answer
387 views

Memcached - one large instance vs many smaller

I will be adding a memcached server to my web app to offload lots of db requests. I'll be mostly caching different small id-name pairs (memberid-membername, blogid-blogname, etc) and expect total ...