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Diffstat (limited to 'HOWTO')
| -rw-r--r-- | HOWTO/INSTALL.md | 45 | ||||
| -rw-r--r-- | HOWTO/OTP-PATCH-APPLY.md | 144 |
2 files changed, 172 insertions, 17 deletions
diff --git a/HOWTO/INSTALL.md b/HOWTO/INSTALL.md index 53b1b8cd8a..7efea77d4c 100644 --- a/HOWTO/INSTALL.md +++ b/HOWTO/INSTALL.md @@ -417,22 +417,33 @@ important when building Erlang/OTP. By default the VM will refuse to build if native atomic memory operations are not available. Erlang/OTP itself provides implementations of native atomic memory operations -that can be used when compiling with a `gcc` compatible compiler on 32-bit -and 64-bit x86, 32-bit and 64-bit SPARC V9, and 32-bit PowerPC. When compiling -with a `gcc` compatible compiler on other architectures, the VM may be able to -make use of native atomic operations using the `__sync_*` primitives, but this -should only be used as a last resort since this wont give you optimal -performance. When compiling on Windows using a MicroSoft Visual C++ compiler -native atomic memory operations are provided by Windows APIs. - -You are recommended to use the native atomic implementation provided by -Erlang/OTP, or the API provided by Windows. If these do not provide native -atomics on your platform, you are recommended to build and install -[libatomic_ops][] before building Erlang/OTP. The `libatomic_ops` library -provides native atomic memory operations for a variety of platforms and -compilers. When building Erlang/OTP you need to inform the build system of -where the `libatomic_ops` library is installed using the -`--with-libatomic_ops=PATH` configure switch. +that can be used when compiling with a `gcc` compatible compiler for 32/64-bit +x86, 32/64-bit SPARC V9, 32-bit PowerPC, or 32-bit Tile. When compiling with +a `gcc` compatible compiler for other architectures, the VM may be able to make +use of native atomic operations using the `__atomic_*` builtins (may be +available when using a `gcc` of at least version 4.7) and/or using the +`__sync_*` builtins (may be available when using a `gcc` of at least version +4.1). If only the `gcc`'s `__sync_*` builtins are available, the performance +will suffer. Such a configuration should only be used as a last resort. When +compiling on Windows using a MicroSoft Visual C++ compiler native atomic +memory operations are provided by Windows APIs. + +Native atomic implementation in the order preferred: +1. The implementation provided by Erlang/OTP. +2. The API provided by Windows. +3. The implementation based on the `gcc` `__atomic_*` builtins. +4. If none of the above are available for your architecture/compiler, you + are recommended to build and install [libatomic_ops][] before building + Erlang/OTP. The `libatomic_ops` library provides native atomic memory + operations for a variety of architectures and compilers. When building + Erlang/OTP you need to inform the build system of where the + `libatomic_ops` library is installed using the + `--with-libatomic_ops=PATH` `configure` switch. +5. As a last resort, the implementation solely based on the `gcc` + `__sync_*` builtins. This will however cause lots of expensive and + unnecessary memory barrier instructions to be issued. That is, + performance will suffer. The `configure` script will warn at the end + of its execution if it cannot find any other alternative than this. ### Building ### @@ -849,7 +860,7 @@ Copyright and License %CopyrightBegin% -Copyright Ericsson AB 1998-2014. All Rights Reserved. +Copyright Ericsson AB 1998-2015. All Rights Reserved. The contents of this file are subject to the Erlang Public License, Version 1.1, (the "License"); you may not use this file except in diff --git a/HOWTO/OTP-PATCH-APPLY.md b/HOWTO/OTP-PATCH-APPLY.md new file mode 100644 index 0000000000..2aa31629ef --- /dev/null +++ b/HOWTO/OTP-PATCH-APPLY.md @@ -0,0 +1,144 @@ +Patching OTP Applications +========================= + +Introduction +------------ + +This document describes the process of patching an existing OTP +installation with one or more Erlang/OTP applications of newer versions +than already installed. The tool `otp_patch_apply` is available for this +specific purpose. It resides in the top directory of the Erlang/OTP +source tree. + +The `otp_patch_apply` tool utilizes the [runtime_dependencies][] tag in +the [application resource file][]. This information is used to determine +if the patch can be installed in the given Erlang/OTP installation +directory. + +Read more about the [version handling][] introduced in Erlang/OTP release +17, which also describes how to determine if an installation includes one +or more patched applications. + +If you want to apply patches of multiple OTP applications that resides +in different OTP versions, you have to apply these patches in multiple +steps. It is only possible to apply multiple OTP applications from the +same OTP version at once. + +Prerequisites +------------- + +It's assumed that the reader is familiar with +[building and installing Erlang/OTP][]. To be able to patch an +application, the following must exist: + +* An Erlang/OTP installation. + +* An Erlang/OTP source tree containing the updated applications that + you want to patch into the existing Erlang/OTP installation. + +Using otp\_patch\_apply +----------------------- + +> *WARNING*: Patching applications is a one-way process. +> Create a backup of your OTP installation directory before +> proceeding. + +First of all, build the OTP source tree at `$ERL_TOP` containing +the updated applications. + +> *NOTE*: Before applying a patch you need to do a *full* build +> of OTP in the source directory. + +If you are building in `git` you first need to generate the +`configure` scripts: + + $ ./otp_build autoconf + +Configure and build all applications in OTP: + + $ configure + $ make + +or + + $ ./otp_build configure + $ ./otp_build boot -a + +If you have installed documentation in the OTP installation, also +build the documentation: + + $ make docs + +After the successful build it's time to patch. The source tree directory, +the directory of the installation and the applications to patch are given +as arguments to `otp_patch_apply`. The dependencies of each application +are validated against the applications in the installation and the other +applications given as arguments. If a dependency error is detected, the +script will be aborted. + +The `otp_patch_apply` syntax: + + $ otp_patch_apply -s <Dir> -i <Dir> [-l <Dir>] [-c] [-f] [-h] \ + [-n] [-v] <App1> [... <AppN>] + + -s <Dir> -- OTP source directory that contains build results. + -i <Dir> -- OTP installation directory to patch. + -l <Dir> -- Alternative OTP source library directory path(s) + containing build results of OTP applications. + Multiple paths should be colon separated. + -c -- Cleanup (remove) old versions of applications + patched in the installation. + -f -- Force patch of application(s) even though + dependencies are not fulfilled (should only be + considered in a test environment). + -h -- Print help then exit. + -n -- Do not install documentation. + -v -- Print version then exit. + <AppX> -- Application to patch. + + Environment Variable: + ERL_LIBS -- Alternative OTP source library directory path(s) + containing build results of OTP applications. + Multiple paths should be colon separated. + +> *NOTE*: The complete build environment is required while running +> `otp_patch_apply`. + +> *NOTE*: All source directories identified by `-s` and `-l` should +> contain build results of OTP applications. + +For example, if the user wants to install patched versions of `mnesia` +and `ssl` built in `/home/me/git/otp` into the OTP installation +located in `/opt/erlang/my_otp` type + + $ otp_patch_apply -s /home/me/git/otp -i /opt/erlang/my_otp \ + mnesia ssl + +> *NOTE*: If the list of applications contains core applications, +> i.e `erts`, `kernel`, `stdlib` or `sasl`, the `Install` script in +> the patched Erlang/OTP installation must be rerun. + +The patched applications are appended to the list of installed +applications. Take a look at +`<InstallDir>/releases/OTP-REL/installed_application_versions`. + +Sanity check +------------ + +The application dependencies can be checked using the Erlang shell. +Application dependencies are verified among installed applications by +`otp_patch_apply`, but these are not necessarily those actually loaded. +By calling `system_information:sanity_check()` one can validate +dependencies among applications actually loaded. + + 1> system_information:sanity_check(). + ok + +Please take a look at the reference of [sanity_check()][] for more +information. + +[application resource file]: kernel:app +[runtime_dependencies]: kernel:app#runtime_dependencies +[building and installing Erlang/OTP]: INSTALL.md +[version handling]: ../system_principles/versions +[sanity_check()]: runtime_tools:system_information#sanity_check-0 |