Automated builds of gRPC

Introduction

gRPC is a nice piece of software, but getting a working version of it can be a challenge! This project provides small scripts that manage all the little details on various systems.

Once the build has completed, the script will generate a compressed package containnig the gRPC & protobuf tools that generate code, plus the headers and static libs required to compile the generated code.

• The x86_64 packages were built via Travis CI and automatically uploaded to GitHub.
• The ARM packages were built on the targeted device and manually uploaded.

Binary packages for gRPC

Note: gRPC v1.0.0 is not usable because of a bug in the build system (see #8606)

You will find binary packages on the release page. The supported platforms are:

• Linux 64 bits (Travis-CI)
  • gcc 4.8.1, 5.4.1, 6.2.0
  • clang 3.5.0, 3.7.1, 3.8.1
• ARMv6 (Raspberry Pi model B)
  • gcc 4.9.2

What do the scripts do?

The script will:

• install cmake if not available / existing version is too old
• clone grpc source code + its submodules
• detect and prevent possible build issues by patching the source
• build grpc in debug and release
• create a tar.gz package

The possible issues that are fixed by the script are:

• dependency BoringSSL (Google fork of OpenSSL) won't build on armv6l or armv7l such as Raspberry Pi or NVidia Tegra (issue #8719)
• third_party/zlib references system wide zlib when building examples (issue #8739)
• build will fail because of a link error on some systems (Ubuntu 12.04)
• make install fails on protobuf when it is part of gRPC

Requirements to run the script

• must: bash
• must: git
• must: gcc >= 4.8 or clang >= 3.5 (required to build gRPC)
• must: go (apt-get install golang)
• recommened: cmake >= 3. If not, the script will download / build it (requires extra time)

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Build times

Note: the reported times include the cmake phase. They are ordered by total build time (lower is better).

gcc vs clang on Intel x64 (Travis-CI)

Dual Intel Xeon 2.8GHz (32 logical cores):

compiler	total	debug	release
clang-3.5.0	48 sec	22 sec	28 sec
clang-3.7.1	52 sec	22 sec	30 sec
gcc-4.8.1	55 sec	20 sec	33 sec
gcc-5.4.1	55 sec	22 sec	33 sec
clang-3.8.1	65 sec	27 sec	38 sec
gcc-6.2.0	68 sec	28 sec	40 sec

Raspberry Pi 1 Model B

ARMv6 700 MHz (1 logical core):

compiler	total	debug	release
gcc-4.9.2	4h:03min	2h:22min	3h:41min

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Lessons learned

I learned many things while working on this project. Here's a quick summary.

Travis

Using sudo: false to run on container-based infrastructure rather than virtual machines:

• makes each job run almost 6 times faster via the use of 32 cores!
• makes installation of dependencies much faster (apt-get install vs using docker images)
• allows to run in parallel 5 jobs rather than 2 with open source projets
• makes builds start faster after each commit (almost immediately)

As a result, building 6 targets is done in less than 5 minutes rather than +1 hour!

Bash tricks

• redirecting both stdout and stderr with &> rather than > cmd 2>&1
  • GCCVER=`gcc -v 2>&1 | grep "gcc version" | awk '{print $3}'`
• regex testing:
  • [[ "$GCCVER" == "4."* ]] && [[ $GCCVER =~ 4.[0-7].* ]]
• testing if a command exists:
  • go version &> /dev/null || echo "not available!"
  • if ! cmake -version &> /dev/null ; then
• patching a line in a file:
  • sed -i -- 's/oldtext/newtext/g' $FILENAME
• truncate a file at line number:
  • sed --in-place -n "1,$((LINE_NUMBER-1)) p" $FILE
• use bash built-in variable $SECONDS to compute duration of a command:
  • SECONDS=0
  • command
  • echo "Duration: $(($SECONDS / 60)) min $(($SECONDS % 60)) sec
• use env and CC/CXX environment variables to run make with C/C++ compilers different from the default ones:
  • env CC=gcc-6 CXX=g++-6 make
• use readonly or declare -r to declare read-only variables (modifying them will cause an error)

Linux

• nproc returns the number of physical cores. Use nproc --all to get the logical ones.
• While uname -m (machine) and uname -p (processor) often give the same results, on Raspberry Pi (Raspbian Jessie Lite) -m returns armv6l while -p returns unknown.