The latest PHP Tracer supports versions >= 5.4.x.
For a full list of Datadog’s PHP version and framework support (including legacy and maintenance versions), see the Compatibility Requirements page.
Follow the Quickstart instructions within the Datadog app for the best experience, including:
service, env, and version tags.For descriptions of terminology used in APM, take a look at the official documentation.
For details about open-source contributions to the PHP tracer, refer to the contributing guide.
Install and configure the Datadog Agent to receive traces from your now instrumented application. By default the Datadog Agent is enabled in your datadog.yaml file under apm_config with enabled: true and listens for trace traffic at localhost:8126. For containerized environments, follow the links below to enable trace collection within the Datadog Agent.
Set apm_non_local_traffic: true in the apm_config section of your main datadog.yaml configuration file.
See the specific setup instructions to ensure that the Agent is configured to receive traces in a containerized environment:
After having instrumented your application, the tracing client sends traces to localhost:8126 by default. If this is not the correct host and port change it by setting the below env variables:
DD_AGENT_HOST and DD_TRACE_AGENT_PORT.
See environment variable configuration for more information on how to set these variables.
DD_SITE in the Datadog Agent to To set up Datadog APM in AWS Lambda, see the Tracing Serverless Functions documentation.
Tracing is available for a number of other environments, such as Heroku, Cloud Foundry, AWS Elastic Beanstalk, and Azure App Service.
For other environments, please refer to the Integrations documentation for that environment and contact support if you are encountering any setup issues.
Download the official installer:
curl -LO https://github.com/DataDog/dd-trace-php/releases/latest/download/datadog-setup.php
Run the installer:
# Full installation: APM + ASM + Profiling (Beta)
php datadog-setup.php --php-bin=all --enable-appsec --enable-profiling
# APM only
php datadog-setup.php --php-bin=all
# APM + ASM
php datadog-setup.php --php-bin=all --enable-appsec
# APM + Profiling (Beta)
php datadog-setup.php --php-bin=all --enable-profiling
This command installs the extension to all the PHP binaries found in the host or container. If --php-bin is omitted, the installer runs in interactive mode and asks the user to select the binaries for installation. The value of --php-bin can be a path to a specific binary in case dd-trace-php should be installed only to such binary.
Restart PHP (PHP-FPM or the Apache SAPI) and visit a tracing-enabled endpoint of your application. For traces, see the APM Service List.
When you do not specify --enable-appsec, the AppSec extension loads shortly at startup, and is not enabled by default. It immediately short-circuits, causing negligible performance overhead.
phpinfo() page from the host machine and scroll down to the `ddtrace`. Failed diagnostic checks appear in this section to help identify any issues./path/to/php-zts --ini to find where Datadog's .ini file is located, then add the -zts suffix from the file name. For example, from extension=ddtrace-20210902.so to extension=ddtrace-20210902-zts.so.Tracing is automatically enabled by default. Once the extension is installed, ddtrace traces your application and sends traces to the Agent.
Datadog supports all web frameworks out of the box. Automatic instrumentation works by modifying PHP’s runtime to wrap certain functions and methods to trace them. The PHP tracer supports automatic instrumentation for several libraries.
Automatic instrumentation captures:
If needed, configure the tracing library to send application performance telemetry data as you require, including setting up Unified Service Tagging. Read Library Configuration for details.
Additional steps are required for instrumenting CLI scripts. Read Trace PHP CLI Scripts for more information.
To upgrade the PHP tracer, download the latest release and follow the same steps as installing the extension.
Once the installation is completed restart PHP (PHP-FPM or the Apache SAPI).
Note: If you are using second level caching in OPcache by setting the parameter opcache.file_cache, remove the cache folder.
To remove the PHP tracer:
98-ddtrace.ini and 99-ddtrace-custom.ini from your php configuration folder.Note: If you are using second level caching in OPcache by setting the parameter opcache.file_cache, remove the cache folder.
In the unusual event of an application crash caused by the PHP tracer, typically because of a segmentation fault, the best thing to do is obtain a core dump or a Valgrind trace and contact Datadog support.
For the core dumps to be readable, debug symbols for the PHP binaries have to be installed on the system that runs PHP.
To check if debug symbols are installed for PHP or PHP-FPM, use gdb.
Install gdb:
apt|yum install -y gdb
Run gdb with the binary of interest. For example for PHP-FPM:
gdb php-fpm
If the gdb output contains a line similar to the text below, then debug symbols are already installed.
...
Reading symbols from php-fpm...Reading symbols from /usr/lib/debug/path/to/some/file.debug...done.
...
If the gdb output contains a line similar to the text below, then debug symbols need to be installed:
...
Reading symbols from php-fpm...(no debugging symbols found)...done.
...
Install package yum-utils that provides the program debuginfo-install:
yum install -y yum-utils
Find the package name for your PHP binaries, it can vary depending on the PHP installation method:
yum list installed | grep php
Install debug symbols. For example for package php-fpm:
debuginfo-install -y php-fpm
Note: If the repository that provides the PHP binaries is not enabled by default, it can be enabled when running the debuginfo-install command. For example:
debuginfo-install --enablerepo=remi-php74 -y php-fpm
If PHP was installed from the Sury Debian DPA, debug symbols are already available from the DPA. For example, for PHP-FPM 7.2:
apt update
apt install -y php7.2-fpm-dbgsym
The Debian project maintains a wiki page with instructions to install debug symbols.
Edit the file /etc/apt/sources.list:
# ... leave here all the pre-existing packages
# add a `deb` deb http://deb.debian.org/debian-debug/ $RELEASE-debug main
# For example for buster
deb http://deb.debian.org/debian-debug/ buster-debug main
Update apt:
apt update
Try canonical package names for debug symbols, first. For example, if the package name is php7.2-fpm try:
apt install -y php7.2-fpm-dbgsym
# if the above does not work
apt install -y php7.2-fpm-dbg
If debug symbols cannot be found, use the utility tool find-dbgsym-packages. Install the binary:
apt install -y debian-goodies
Attempt finding debug symbols from either the full path to the binary or the process id of a running process:
find-dbgsym-packages /usr/sbin/php-fpm7.2
Install the resulting package name, if found:
apt install -y php7.2-fpm-{package-name-returned-by-find-dbgsym-packages}
ppa:ondrej/phpIf PHP was installed from the ppa:ondrej/php, edit the apt source file /etc/apt/sources.list.d/ondrej-*.list by adding the main/debug component.
Before:
deb http://ppa.launchpad.net/ondrej/php/ubuntu <version> main
After:
deb http://ppa.launchpad.net/ondrej/php/ubuntu <version> main main/debug
Update and install the debug symbols. For example, for PHP-FPM 7.2:
apt update
apt install -y php7.2-fpm-dbgsym
Find the package name for your PHP binaries, it can vary depending on the PHP installation method:
apt list --installed | grep php
Note: In some cases php-fpm can be a metapackage that refers to the real package, for example php7.2-fpm in case of PHP-FPM 7.2. In this case the package name is the latter.
Try canonical package names for debug symbols, first. For example, if the package name is php7.2-fpm try:
apt install -y php7.2-fpm-dbgsym
# if the above does not work
apt install -y php7.2-fpm-dbg
If the -dbg and -dbgsym packages cannot be found, enable the ddebs repositories. Detailed information about how to install debug symbols from the ddebs can be found in the Ubuntu documentation.
For example, for Ubuntu 18.04+, enable the ddebs repo:
echo "deb http://ddebs.ubuntu.com $(lsb_release -cs) main restricted universe multiverse" | tee -a /etc/apt/sources.list.d/ddebs.list
echo "deb http://ddebs.ubuntu.com $(lsb_release -cs)-updates main restricted universe multiverse" | tee -a /etc/apt/sources.list.d/ddebs.list
Import the signing key (make sure the signing key is correct):
apt install ubuntu-dbgsym-keyring
apt-key adv --keyserver keyserver.ubuntu.com --recv-keys <SIGNING KEY FROM UBUNTU DOCUMENTATION>
apt update
Try adding the canonical package names for debug symbols. For example, if the package name is php7.2-fpm try:
apt install -y php7.2-fpm-dbgsym
# if the above does not work
apt install -y php7.2-fpm-dbg
In case debug symbols cannot be found, use the utility tool find-dbgsym-packages. Install the binary:
apt install -y debian-goodies
Attempt finding debug symbols from either the full path to the binary or the process id of a running process:
find-dbgsym-packages /usr/sbin/php-fpm7.2
Install the resulting package name, if found:
apt install -y php7.2-fpm-{package-name-returned-by-find-dbgsym-packages}
Obtaining a core dump for PHP applications can be tricky, especially on PHP-FPM. Here are a few tips to help you obtain a core dump:
(SIGSEGV - core dumped) because a message like this means it has been dumped: WARNING: [pool www] child <pid> exited on signal 11 (SIGSEGV - core dumped) after <duration> seconds from start.(SIGSEGV) because a message like this indicates that the core was not dumped: WARNING: [pool www] child <pid> exited on signal 11 (SIGSEGV) after <duration> seconds from start.cat /proc/sys/kernel/core_pattern. The default value is typically core, meaning that a file named core will be generated in the web root folder.If no core dump was generated, check the following configurations and change them as needed:
/proc/sys/kernel/core_pattern contains a path including nested directories, ensure the full directory path exists.root (a common user name is www-data) give that user write permissions to the core dumps directory./proc/sys/fs/suid_dumpable is not 0. Set it to 1 or 2 unless you run PHP-FPM workers pool as root. Check your options with your system administrator.rlimit_core in the PHP-FPM pool configuration section. You can set it to unlimited: rlimit_core = unlimited.ulimit set in your system. You can set it to unlimited: ulimit -c unlimited./proc/sys/* have to be done to the host machine. Contact your system administrator to know the options available to you. If you are able to, try recreating the issue in your testing or staging environments.To gain more details about the crash, run the application with Valgrind. Unlike core dumps, this approach always works in an unprivileged container.
Install Valgrind with your package manager. Run the application with Valgrind enough to generate a few requests.
For a CLI application, run:
USE_ZEND_ALLOC=0 valgrind -- php path/to/script.phpphp-fpm run:USE_ZEND_ALLOC=0 valgrind --trace-children=yes -- php-fpm -F --fpm-config <CONFIG_FILE_PATH> <MORE_OPTIONS>(. /etc/apache2/envvars; USE_ZEND_ALLOC=0 valgrind --trace-children=yes -- apache2 -X)`The resulting Valgrind trace is printed by default to the standard error, follow the official documentation to print to a different target. The expected output is similar to the example below for a PHP-FPM process:
==322== Conditional jump or move depends on uninitialised value(s)
==322== at 0x41EE82: zend_string_equal_val (zend_string.c:403)
==322== ...
==322== ...
==322==
==322== Process terminating with default action of signal 11 (SIGSEGV): dumping core
==322== at 0x73C8657: kill (syscall-template.S:81)
==322== by 0x1145D0F2: zif_posix_kill (posix.c:468)
==322== by 0x478BFE: ZEND_DO_ICALL_SPEC_RETVAL_UNUSED_HANDLER (zend_vm_execute.h:1269)
==322== by 0x478BFE: execute_ex (zend_vm_execute.h:53869)
==322== by 0x47D9B0: zend_execute (zend_vm_execute.h:57989)
==322== by 0x3F6782: zend_execute_scripts (zend.c:1679)
==322== by 0x394F0F: php_execute_script (main.c:2658)
==322== by 0x1FFE18: main (fpm_main.c:1939)
==322==
==322== Process terminating with default action of signal 11 (SIGSEGV)
==322== ...
==322== ...
==322==
==322== HEAP SUMMARY:
==322== in use at exit: 3,411,619 bytes in 22,428 blocks
==322== total heap usage: 65,090 allocs, 42,662 frees, 23,123,409 bytes allocated
==322==
==322== LEAK SUMMARY:
==322== definitely lost: 216 bytes in 3 blocks
==322== indirectly lost: 951 bytes in 32 blocks
==322== possibly lost: 2,001,304 bytes in 16,840 blocks
==322== still reachable: 1,409,148 bytes in 5,553 blocks
==322== of which reachable via heuristic:
==322== stdstring : 384 bytes in 6 blocks
==322== suppressed: 0 bytes in 0 blocks
==322== Rerun with --leak-check=full to see details of leaked memory
==322==
==322== Use --track-origins=yes to see where uninitialised values come from
==322== For lists of detected and suppressed errors, rerun with: -s
==322== ERROR SUMMARY: 18868 errors from 102 contexts (suppressed: 0 from 0)
Some issues are caused by external factors, so it can be valuable to have a strace.
strace is orders of magnitude slower than when running natively. This method is recommended for non-production environments.Install strace with your package manager. When generating a strace to send to Datadog Support, ensure you use the -f option to follow child processes.
For a CLI application, run:
strace -f php path/to/script.phpFor php-fpm, run:
strace -f php-fpm -F --fpm-config <CONFIG_FILE_PATH> <MORE_OPTIONS>For Apache, run:
(. /etc/apache2/envvars; strace -f apache2 -X)Additional helpful documentation, links, and articles:
