Questions tagged [optimization]

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

A system may be optimized so that it executes more rapidly, or is capable of operating with less memory storage or other resources, or draw less power. The optimized system will typically only be optimal in one application or for one audience. For example, one might reduce the amount of time a task takes to perform at the price of making it consume more memory.

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LEFT JOIN Server Performance optimization

I have a query that I want to execute that fastest possible. Here it is: select d.InvoiceDetailId,a.Fee,a.FeeTax from InvoiceDetail d LEFT JOIN InvoiceDetail a on a.AdjustDetailId = d.InvoiceDetailId I put an ascending index on AdjustDetailId…
Jose
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How to convert swap partition from RAID1 to RAID0 using mdadm

How to convert linux SWAP memory from RAID1 to RAID0? Start with:2 exact size swap formatted partitions (/dev/sdc5 and /dev/sdd5) on 2 physically separate disks that are used via Software RAID(named md127, located /dev/md/s) in RAID 1…
dankilev
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mysqld taking 800% CPU since traffic increased on my site, how to fix

i have centos 7 x64 64 GB RAM and 500 GB of SSD dedicated server., And recently cpu usage was really high, $ uptime 13:50:30 up 169 days, 1:53, 1 user, load average: 37.48, 37.64, 33.60 so i noticed mysqld is taking much more CPU PID USER …
user138870
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How to speed up connection with a server in China

I have a EC2 server in China using Amazon AWS China. It's a server with : Apache 2 and PHP The database is a RDS instance running MySQL (also in china) The problem: Access from out of China is very slow. (tested from australia, france and Canada).…
blueweb
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Should a KVM host be doing things other than hosting VMs? (such as ZFS)?

What are the performance and stability implications of running resource intensive services in a hypervisor vs guest OS? I want to set up a workstation with both Linux and Windows, hosted by (probably) KVM. Both will use some of the same services:…
Stonecraft
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nginx multiple paths (too many)

i got this working nginx config: server { listen 80; server_name mydomain.com; root /var/www/mydomain/wordpress; index index.html index.php; location /customer1 { alias /var/www/mydomain/customers/custumer1; } location…
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To which value set ulimit

I'm setting up nginx from what I've understood the worker_connections value must not exceed the maximum number of open file descriptors retruned by ulimit -n. On my fresh 16.04 ubuntu installation ulimit -n return 1024 which is very low comparing…
Slakk
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Recommendations for Java Web Server

I am currently using DBCP for connection pooling since it is more or less provided with tomcat and easy to setup. I am thinking about migrating to Glassfish or Jetty and haven't yet determined which connection pool provider I will use. I am…
Walter White
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Track what is causing AWS RDS to use insanely high bandwidth

We are having a high traffic (100K hit/day) Drupal news website hosted on AWS. Its behind cloudflare & 2 Load Balanced Varnish servers. For some reason the bandwidth usage is very high for RDS. This is after having all the cache tables hosted in…
Safwan Erooth
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Ubuntu LAMP server busy at peak hours

I'm running a Ubuntu 14 server with LAMP on virtual cloud hosting (CityCloud). The server is usually doing very well with response time<0.5s. However, the problems start at peak hours, mainly Monday-Wednesday/Thursday, with response times at around…
jonr
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Optimizing Apache

I've been reading multiple optimization guide for apache and found a lot of data (Although I have no idea what is the experience of the authors). I have a production server with apache 2.2.3, MySQL 5.1.36, Centos 5.3, nginx to act as a reverse proxy…
Adam Benayoun
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Performance issue with Apache, PHP and Symfony

Updated: ================================================================ I finally found the reason with oprofile. It was because the routing cache of Symfony. We have lots of pages with different urls and symfony caches them in one file…
Mickey Shine
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Suggested config for PHP VPS host on Linux for low memory

I'm looking at using Linode at a VPS host for a PHP Webapp. Linode offers a variety of Linux distros. I'm basically after a config that will absolutely minimize memory usage while still keeping the site performant. So how should I configure…
cletus
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My Vps is too Fragile

I am using digitalocean $5 plan. 1 cpu , 512mb ram , mysql + apache , nginx + centos 6.5 + cpanel installed. 2 wordpress site on that. But if I reload page of one of my sites, cpu usage increasing to 50% , 60% .If I check mysite from woorank (SEO…
mrblithe
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MySql table optimization causing more problems than it solves

I have a heavily accessed table corresponding to user's private messages, with over 10 M rows. When I run the user deletion process, obsolete messages are deleted from the table, typically more than 1000 rows. The problem raises when this table is…
andreszs
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