Server Tuning & Performance Tips

There are a number of options to tune the ownCloud installation and enable a high level of performance. The database, for example, needs indexes in the most active tables. The number of live Apache connections needs to be turned up to 1000 or more, and the number of allowed MySQL connections also has to be increased to the same. Turning on the Alternative PHP Cache (APC) will also increase performance on the app servers, and there are likely a number of environment and policy specific configurations needed as well in any given deployment.

This chapter gives a few hands-on tips on how to achieve this.

PHP Version and Information

You will need to know your PHP version and configurations. To do this, create a plain-text file named phpinfo.php and place it in your Web root, for example /var/www/html/phpinfo.php. (Your Web root may be in a different location; your Linux distribution documentation will tell you where.) This file contains just this line:

<?php phpinfo(); ?>

Open this file in a Web browser:

../_images/phpinfo.png

Your PHP version is at the top, and the rest of the page contains abundant system information such as active modules, active .ini files, and much more. When you are finished reviewing your information you must delete phpinfo.php, or move it outside of your Web directory, because it is a security risk to expose such sensitive data.

General Linux tuning

System configuration overview

# cat /etc/sysctl.conf
...
net.core.somaxconn = 4096
net.ipv4.tcp_max_syn_backlog = 2048
...
# ulimit -nH 4096

Make sure that your /tmp is in ramdisk which improves session handling performance. To do so, add the following to /etc/fstab:

none /tmp tmpfs,size=6g defaults

Caching

Caching improves performance by storing data, code, and other objects in memory.

The APC or OPCache bytecode cache are commonly used in PHP environments. This example installs APC on CentOS/Red Hat/Fedora systems running PHP 5.4:

$ sudo yum install php-pecl-apc

On Ubuntu systems running PHP 5.4 this command installs APC:

$ sudo apt-get install php-apc

PHP 5.5 replaces APC with OPCache. OPCache is bundled with PHP 5.5 so it should not be necessary to install it separately. OPCache improves PHP performance by storing precompiled script bytecode in shared memory, thereby removing the need for PHP to load and parse scripts on each request. This extension is bundled with PHP 5.5.0 and later, and is available in PECL for PHP versions 5.2, 5.3, and 5.4.

APC is both an opcode cache and data store. OPCache is only an opcode cache, so for caching user data you should also install APCu.

The Redis key-value cache and store is an excellent fast and robust cache. For configuration examples see Config.php Parameters.

Distributed PHP environments should use Memcached. Memcached servers must be specified in the memcached_servers array in ownCloud’s config file config.php. For examples see Config.php Parameters.

Tuning System Parameters

Configuration for more concurrent requests.

echo "2048 64512" > /proc/sys/net/ipv4/ip_local_port_range
echo "1" > /proc/sys/net/ipv4/tcp_tw_recycle
echo "1" > /proc/sys/net/ipv4/tcp_tw_reuse
echo "10" > /proc/sys/net/ipv4/tcp_fin_timeout

echo "65536" > /proc/sys/net/core/somaxconn
echo "65536" > /proc/sys/net/ipv4/tcp_max_syn_backlog
echo "262144" > /proc/sys/net/netfilter/nf_conntrack_max

Check if the values have been set accordingly:

# cat /proc/sys/net/ipv4/ip_local_port_range
2048 64512
# cat /proc/sys/net/ipv4/tcp_tw_recycle
1
# cat /proc/sys/net/ipv4/tcp_tw_reuse
1
# cat /proc/sys/net/ipv4/tcp_fin_timeout
10
# cat /proc/sys/net/core/somaxconn
65536
# cat /proc/sys/net/ipv4/tcp_max_syn_backlog
65536
# cat /proc/sys/net/netfilter/nf_conntrack_max
262144

Next, persist the settings across reboots by adding them into /etc/sysctl.conf:

net.ipv4.ip_local_port_range = 2048 64512
net.ipv4.tcp_tw_recycle = 1
net.ipv4.tcp_tw_reuse = 1
net.ipv4.tcp_fin_timeout = 10

net.core.somaxconn = 65536
net.ipv4.tcp_max_syn_backlog = 65536
net.netfilter.nf_conntrack_max = 262144

Tuning Memory

Add RAM disk to fstab:

- none /var/www/html tmpfs defaults,size=6g

Move PHP Code into RAM Disk:

# mv /var/www/html /var/www/html_fs

Copy ownCloud installation to RAM Disk and symlink storage to ownCloud data directory.

Note

ram disks are not reboot-safe. You need to establish a way to persist them, for instance by using cp or rsync to transfer them from a location on the hard disk to the ram disk before apache starts.

ownCloud Server Tuning

Serving static files via web server

See the section Serving Static Files for Better Performance for a description and the benefits.

Using cron to perform background jobs

See the section Defining Background Jobs for a description and the benefits.

Enable JavaScript and CSS Asset Management

See the section JavaScript and CSS Asset Management for a description and the benefits.

SSL / Encryption App

SSL (HTTPS) and file encryption/decryption can be offloaded to a processor’s AES-NI extension. This can both speed up these operations while lowering processing overhead. This requires a processor with the AES-NI instruction set.

Here are some examples how to check if your CPU / environment supports the AES-NI extension:

  • For each CPU core present: grep flags /proc/cpuinfo or as a summary for all cores: grep -m 1 ^flags /proc/cpuinfo If the result contains any aes, the extension is present.
  • On Windows you can run coreinfo from Sysinternals Windows Sysinternals Download Coreinfo which gives you details of the processor and extensions present. Note: you may have to run the command shell as administrator to get an output.
  • Search eg. on the Intel web if the processor used supports the extension Intel Processor Feature Filter You may set a filter by "AES New Instructions" to get a reduced result set.
  • For versions of openssl >= 1.0.1, AES-NI does not work via an engine and will not show up in the openssl engine command. It is active by default on the supported hardware. You can check the openssl version via openssl version -a
  • If your processor supports AES-NI but it does not show up eg via grep or coreinfo, it is maybe disabled in the BIOS.
  • If your environment runs virtualized, check the virtualization vendor for support.

SSL session reuse

You should enable SSL session tickets or SSL session identifiers in your web server. This will lead to lower delay in connection setup time for TCP connections to the ownCloud.

Webserver Tips

Enable the SPDY protocol

Your webserver can be configured to use the SPDY protocol which could improve the overall performance of ownCloud. Please have a look at the documentation of your webservers module for more information:

Note

If you want to enable SPDY for Apache please note the Known Issues of this module to avoid problems after enabling it.

Apache Tuning

Maximum number Apache processes

An Apache process is using around 12MB of RAM. Apache should be configured that the maximum number of HTTPD processes time 12MB is lower than the amount of RAM. Otherwise the system begins to swap and the performance goes down. In this case the maximum number is set to 6000.

KeepAlive should be configured with sensible defaults

KeepAlive On
KeepAliveTimeout 2
MaxKeepAliveRequests 10

mod_gzip

mod_gzip should be used because it speeds up the transfer of data and helps to free server memory, and HTTP connections are closed faster.

PHP safe mode

PHP safe mode has to be turned off. It is deprecated and will be removed in newer PHP versions.

MPM

Apache prefork has to be used. Don’t use threaded mpm with mod_php because PHP is currently not thread safe.

Hostname Lookups

# cat /etc/httpd/conf/httpd.conf
...
HostnameLookups off

Log files

Log files should be switched off for maximum performance.

Comment out the CustomLog` directive. Keep ErrorLog to be able to track down errors.

MaxKeepAliveRequests 4096

<IfModule prefork.c>
        StartServers 100
        MinSpareServers 100
        MaxSpareServers 2000
        ServerLimit 6000
        MaxClients 6000
        MaxRequestsPerChild 4000
</IfModule>

<Directory "/var/www/html">
        Options Indexes SymLinksIfOwnerMatch AllowOverride All
</Directory>

Database Best Practice

Currently ownCloud supports the following relational database management systems:

  • MySQL
  • MariaDB
  • PostgreSQL
  • SQLite
  • Oracle
  • Mssql

We are using the doctrine database abstraction layer and schema evolution with a MDB2 Schema based table description in XML.

The default indexes are chosen to support every day usage. Additional indexes might further improve the performance.

Using MariaDB/MySQL instead of SQLite

MySQL or MariaDB are preferred because of the performance limitations of SQLite with highly concurrent applications, like ownCloud.

On large instances you could consider running MySQLTuner to optimize the database.

See the section Database Configuration how to configure ownCloud for MySQL or MariaDB. If your installation is already running on SQLite then it is possible to convert to MySQL or MariaDB using the steps provided in Converting Database Type.

Improve slow performance with MySQL on Windows

On Windows hosts running MySQL on the same system changing the parameter dbhost in your config/config.php from localhost to 127.0.0.1 could improve the page loading time.

See also this forum thread.

MySQL / MariaDB

Additional indexes may improve performance.

Index on uid in oc_group_user:

create index oc_group_user_uid on oc_group_user(uid);

Index on oc_share:

create index oc_share_file_target on oc_share(file_target);

Index on oc_filecache:

create index oc_filepath on oc_filecache(storage,size);

Index on oc_files_versions:

create index oc_files_versions_user  on oc_files_versions(user);

Index on oc_files_trashsize:

create index oc_files_trashsize_user  on oc_files_trashsize(user);

Progress of adding them to the default code is tracked in https://github.com/owncloud/core/issues/7474.

Other performance improvements

Mysql: compare https://tools.percona.com/wizard to your current settings MariaDB: https://mariadb.com/kb/en/optimization-and-tuning/

Postgresql

Alternative to MariaDB/MySQL. Used in production by a few core developers.

Migration

Requires at least Postgresql 9.0

Additional Indexes

The ones from MySQL should work just fine. Progress of adding them to the default code is tracked in https://github.com/owncloud/core/issues/7474.

Oracle Database

Usage scenario: Existing enterprise installations. Only core apps are supported and tested. Not recommended because it involves compiling the oci8

Additional Indexes

The ones from mysql should work just fine. Progress of adding them to the default code is tracked in https://github.com/owncloud/core/issues/7474.

Other performance improvements

http://de.slideshare.net/cjorcl/best-practices-php-and-the-oracle-database and ask your DBA.

Problems

When ORA-56600 occurs (Oracle Bug 8467564) set this php.ini setting: oci8.statement_cache_size=1000, see oracle forum discussion

Microsoft SQL Server

Usage scenario: Only core apps are supported. Not even tested by Jenkins.

Additional Indexes

The ones from mysql should work just fine. Progress of adding them to the default code is tracked in https://github.com/owncloud/core/issues/7474.